grepcent / static financial knowledge base

PROASSURANCE CORP (PRA)

CIK: 0001127703. SIC: 6331 Fire, Marine & Casualty Insurance. Latest 10-K as of: 2026-02-23.

SIC breadcrumb: Finance, Insurance, And Real Estate > Insurance Carriers > SIC 6331 Fire, Marine & Casualty Insurance

SEC company page: https://www.sec.gov/edgar/browse/?CIK=1127703. Latest filing source: 0001127703-26-000008.

Informational only - descriptive public-record data, not investment advice.

Business

Read PRA's verbatim Item 1 Business section from its latest 10-K: Business.

Risk Factors

Read PRA's verbatim Item 1A Risk Factors from its latest 10-K: Risk Factors.

Selected Fundamentals

MetricValueUnitFYFiled
Revenue1,098,028,000USD20252026-02-23
Net income50,915,000USD20252026-02-23
Assets5,447,192,000USD20252026-02-23

Financials

Annual standardized facts from SEC companyfacts as of latest extracted filing date 2026-02-23. Source: https://data.sec.gov/api/xbrl/companyfacts/CIK0001127703.json. Derived margins, ratios, and free cash flow are computed from the extracted annual SEC facts.

Download these verified figures (annual + quarterly, with per-value filing provenance): JSON · CSV

Flow metrics use full-year FY periods from 10-K/10-K/A filings; balance-sheet metrics use FY-end instants. Free cash flow = operating cash flow - capital expenditures. Missing metrics are omitted rather than fabricated.

Metric2016201720182019202020212022202320242025
Revenue870,214,000866,149,000886,030,000999,834,000874,940,0001,124,410,0001,106,688,0001,137,212,0001,150,404,0001,098,028,000
Net income151,081,000107,264,00047,057,0001,004,000-175,727,000144,124,000-402,000-38,604,00052,744,00050,915,000
Diluted EPS2.832.000.880.02-3.262.67-0.01-0.731.030.99
Operating cash flow178,983,000173,388,000177,265,000148,166,00092,343,00073,970,000-29,841,000-49,885,000-10,715,000-25,620,000
Dividends paid118,812,000315,228,000316,476,00093,204,00038,664,00010,758,00010,768,0005,379,0000.000.00
Assets5,065,181,0004,929,197,0004,600,726,0004,805,599,0004,654,803,0006,191,477,0005,699,999,0005,631,925,0005,574,273,0005,447,192,000
Liabilities3,266,479,0003,334,402,0003,077,724,0003,293,686,0003,305,593,0004,763,090,0004,595,981,0004,519,945,0004,372,524,0004,098,058,000
Stockholders' equity1,798,702,0001,594,795,0001,523,002,0001,511,913,0001,349,210,0001,428,387,0001,104,018,0001,111,980,0001,201,749,0001,349,134,000
Cash and cash equivalents117,347,000134,495,00080,471,000175,369,000215,782,000143,602,00029,959,00065,898,00054,881,00036,494,000

Ratios

ROE and ROA use period-end equity/assets. Liabilities / equity uses total liabilities divided by stockholders' equity. Current ratio uses current assets divided by current liabilities when both are reported.

Metric2016201720182019202020212022202320242025
Net margin17.36%12.38%5.31%0.10%-20.08%12.82%-0.04%-3.39%4.58%4.64%
Return on equity8.40%6.73%3.09%0.07%-13.02%10.09%-0.04%-3.47%4.39%3.77%
Return on assets2.98%2.18%1.02%0.02%-3.78%2.33%-0.01%-0.69%0.95%0.93%
Liabilities / equity1.822.092.022.182.453.334.164.063.643.04

Industry Peer Context

Each number-line places PRA against the min, median, and max of latest reported values among companies in the same SIC industry when at least three peers report that ratio.

Net margin peer context

PRA Net margin versus SIC peer range. Source: grepcent computed from latest SEC companyfacts ratios for SIC industry 6331; peer count 51.PRA Net margin versus SIC peer range. Source: grepcent computed from latest SEC companyfacts ratios for SIC industry 6331; peer count 51.51 SIC peersMin -22.4%Median 12.3%Max 38.4%PRA 4.6%

ROE peer context

PRA ROE versus SIC peer range. Source: grepcent computed from latest SEC companyfacts ratios for SIC industry 6331; peer count 53.PRA ROE versus SIC peer range. Source: grepcent computed from latest SEC companyfacts ratios for SIC industry 6331; peer count 53.53 SIC peersMin -67.6%Median 15.9%Max 39.9%PRA 3.8%

ROA peer context

PRA ROA versus SIC peer range. Source: grepcent computed from latest SEC companyfacts ratios for SIC industry 6331; peer count 53.PRA ROA versus SIC peer range. Source: grepcent computed from latest SEC companyfacts ratios for SIC industry 6331; peer count 53.53 SIC peersMin -8.6%Median 3.9%Max 15.2%PRA 0.9%

Financial Charts

PRA revenue, last 5 periods. Source: SEC companyfacts FY2025.PRA revenue, last 5 periods. Source: SEC companyfacts FY2025.PRA RevenueLatest point: FY2025 = $1.1BSource: SEC companyfacts FY2025.Fiscal yearReported revenue$0.0B$1.0B$2.0BFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001127703-26-000008; filed 2026-02-23. Concept: Revenues. Source concepts: us-gaap:Revenues.

PRA net income, last 5 periods. Source: SEC companyfacts FY2025.PRA net income, last 5 periods. Source: SEC companyfacts FY2025.PRA Net incomeLatest point: FY2025 = $50.9MSource: SEC companyfacts FY2025.Fiscal yearNet income-$250.0M$0.0B$250.0MFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001127703-26-000008; filed 2026-02-23. Concept: NetIncomeLoss. Source concepts: us-gaap:NetIncomeLoss.

PRA diluted eps, last 5 periods. Source: SEC companyfacts FY2025.PRA diluted eps, last 5 periods. Source: SEC companyfacts FY2025.PRA Diluted EPSLatest point: FY2025 = $0.99/shareSource: SEC companyfacts FY2025.Fiscal yearDiluted EPS (USD/share)-$1.00/share$0.00/share$4.00/shareFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001127703-26-000008; filed 2026-02-23. Concept: EarningsPerShareDiluted. Source concepts: us-gaap:EarningsPerShareDiluted.

PRA operating cash flow, last 5 periods. Source: SEC companyfacts FY2025.PRA operating cash flow, last 5 periods. Source: SEC companyfacts FY2025.PRA Operating cash flowLatest point: FY2025 = -$25.6MSource: SEC companyfacts FY2025.Fiscal yearOperating cash flow-$250.0M$0.0B$250.0MFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001127703-26-000008; filed 2026-02-23. Concept: NetCashProvidedByUsedInOperatingActivities. Source concepts: us-gaap:NetCashProvidedByUsedInOperatingActivities.

PRA dividends paid, last 5 periods. Source: SEC companyfacts FY2025.PRA dividends paid, last 5 periods. Source: SEC companyfacts FY2025.PRA Dividends paidLatest point: FY2025 = $0.0BSource: SEC companyfacts FY2025.Fiscal yearDividends paid$0.0B$125.0M$250.0MFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001127703-26-000008; filed 2026-02-23. Concept: PaymentsOfDividendsCommonStock. Source concepts: us-gaap:PaymentsOfDividendsCommonStock.

PRA assets, last 5 periods. Source: SEC companyfacts FY2025.PRA assets, last 5 periods. Source: SEC companyfacts FY2025.PRA AssetsLatest point: FY2025 = $5.4BSource: SEC companyfacts FY2025.Fiscal yearAssets$0.0B$4.0B$8.0BFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001127703-26-000008; filed 2026-02-23. Concept: Assets. Source concepts: us-gaap:Assets.

PRA liabilities, last 5 periods. Source: SEC companyfacts FY2025.PRA liabilities, last 5 periods. Source: SEC companyfacts FY2025.PRA LiabilitiesLatest point: FY2025 = $4.1BSource: SEC companyfacts FY2025.Fiscal yearLiabilities$0.0B$3.0B$6.0BFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001127703-26-000008; filed 2026-02-23. Concept: Liabilities. Source concepts: us-gaap:Liabilities.

PRA stockholders' equity, last 5 periods. Source: SEC companyfacts FY2025.PRA stockholders' equity, last 5 periods. Source: SEC companyfacts FY2025.PRA Stockholders' equityLatest point: FY2025 = $1.3BSource: SEC companyfacts FY2025.Fiscal yearStockholders' equity$0.0B$1.0B$2.0BFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001127703-26-000008; filed 2026-02-23. Concept: StockholdersEquity. Source concepts: us-gaap:StockholdersEquity.

PRA cash and cash equivalents, last 5 periods. Source: SEC companyfacts FY2025.PRA cash and cash equivalents, last 5 periods. Source: SEC companyfacts FY2025.PRA Cash and cash equivalentsLatest point: FY2025 = $36.5MSource: SEC companyfacts FY2025.Fiscal yearCash and cash equivalents$0.0B$125.0M$250.0MFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001127703-26-000008; filed 2026-02-23. Concept: CashAndCashEquivalentsAtCarryingValue. Source concepts: us-gaap:CashAndCashEquivalentsAtCarryingValue.

Quarterly

Quarterly standardized facts from SEC companyfacts as of latest extracted filing date 2026-05-05. Source: https://data.sec.gov/api/xbrl/companyfacts/CIK0001127703.json.

Flow metrics use discrete quarter-length periods from 10-Q/10-Q/A filings. Q4 revenue and net income are derived only when annual FY and nine-month YTD facts exist for the same fiscal year; derived Q4 values are labeled. EPS Q4 is not derived.

QuarterEnd DateRevenueNet IncomeDiluted EPSMethod
2022-Q22022-06-30-0.03reported discrete quarter
2022-Q32022-09-30-0.17reported discrete quarter
2023-Q12023-03-31-0.11reported discrete quarter
2023-Q22023-06-30291,831,00010,627,0000.20reported discrete quarter
2023-Q32023-09-30275,747,000-49,434,000-0.95reported discrete quarter
2023-Q42023-12-31296,960,0006,377,000derived Q4 = FY annual - nine-month YTD
2024-Q12024-03-31284,697,0004,626,0000.09reported discrete quarter
2024-Q22024-06-30290,355,00015,508,0000.30reported discrete quarter
2024-Q32024-09-30285,253,00016,441,0000.32reported discrete quarter
2024-Q42024-12-31290,100,00016,169,000derived Q4 = FY annual - nine-month YTD
2025-Q12025-03-31272,079,000-5,822,000-0.11reported discrete quarter
2025-Q22025-06-30276,753,00021,921,0000.42reported discrete quarter
2025-Q32025-09-30279,554,0001,446,0000.03reported discrete quarter
2025-Q42025-12-31269,643,00033,370,000derived Q4 = FY annual - nine-month YTD
2026-Q12026-03-31262,634,0008,461,0000.16reported discrete quarter

Quarterly Charts

PRA quarterly revenue, last 12 periods. Source: SEC companyfacts 2026-Q1.PRA quarterly revenue, last 12 periods. Source: SEC companyfacts 2026-Q1.PRA Quarterly RevenueLatest point: 2026-Q1 = $262.6MSource: SEC companyfacts 2026-Q1.Fiscal quarterQuarterly Revenue$0.0B$250.0M$500.0M2023-Q22023-Q32023-Q42024-Q12024-Q22024-Q32024-Q42025-Q12025-Q22025-Q32025-Q42026-Q1

Figure provenance: SEC companyfacts. Latest point: FY 2026 ended 2026-03-31; accession 0001127703-26-000019; filed 2026-05-05. Concept: Revenues. Source concepts: us-gaap:Revenues.

PRA quarterly net income, last 12 periods. Source: SEC companyfacts 2026-Q1.PRA quarterly net income, last 12 periods. Source: SEC companyfacts 2026-Q1.PRA Quarterly Net incomeLatest point: 2026-Q1 = $8.5MSource: SEC companyfacts 2026-Q1.Fiscal quarterQuarterly Net income-$250.0M$0.0B$250.0M2023-Q22023-Q32023-Q42024-Q12024-Q22024-Q32024-Q42025-Q12025-Q22025-Q32025-Q42026-Q1

Figure provenance: SEC companyfacts. Latest point: FY 2026 ended 2026-03-31; accession 0001127703-26-000019; filed 2026-05-05. Concept: NetIncomeLoss. Source concepts: us-gaap:NetIncomeLoss.

PRA quarterly diluted eps, last 12 periods. Source: SEC companyfacts 2026-Q1.PRA quarterly diluted eps, last 12 periods. Source: SEC companyfacts 2026-Q1.PRA Quarterly Diluted EPSLatest point: 2026-Q1 = $0.16/shareSource: SEC companyfacts 2026-Q1.Fiscal quarterQuarterly Diluted EPS (USD/share)-$1.00/share$0.00/share$1.00/share2022-Q22022-Q32023-Q12023-Q22023-Q32024-Q12024-Q22024-Q32025-Q12025-Q22025-Q32026-Q1

Figure provenance: SEC companyfacts. Latest point: FY 2026 ended 2026-03-31; accession 0001127703-26-000019; filed 2026-05-05. Concept: EarningsPerShareDiluted. Source concepts: us-gaap:EarningsPerShareDiluted.

Macro Cross-References

Latest quarter (10-Q)

Latest 10-Q source: 0001127703-26-000019.

Extracted structurally from real Item 2 body heading to real Item 3/4 boundary. Confidence: high. Filing date: 2026-05-05. Report date: 2026-03-31.

ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

The following discussion should be read in conjunction with the Condensed Consolidated Financial Statements and Notes to those statements which accompany this report. Throughout the discussion we use certain terms and abbreviations, which can be found in the Glossary of Terms and Acronyms at the beginning of this report. In addition, a glossary of insurance terms and phrases is available on the investor section of our website. Throughout the discussion, references to "ProAssurance," "ProAssurance Group," "PRA," "Company," "we," "us" and "our" refer to ProAssurance Corporation and its consolidated subsidiaries. The discussion contains certain forward-looking information that involves significant risks, assumptions and uncertainties. As discussed under the heading "Caution Regarding Forward-Looking Statements," our actual financial condition and results of operations could differ significantly from these forward-looking statements.

ProAssurance Overview

ProAssurance Corporation is a holding company for property and casualty insurance companies. Our insurance subsidiaries provide medical professional liability insurance, liability insurance for medical technology and life sciences risks and workers' compensation insurance. Additional information on ProAssurance's four operating and reportable segments is included in Note 12 of the Notes to Condensed Consolidated Financial Statements, Note 15 of the Notes to Consolidated Financial Statements in our December 31, 2025 report on Form 10-K and in the Segment Results sections herein that follow.

Critical Accounting Estimates

Our Condensed Consolidated Financial Statements are prepared in conformity with GAAP. Preparation of these financial statements requires us to make estimates and assumptions that affect the amounts we report on those statements. We evaluate these estimates and assumptions on an ongoing basis based on current and historical developments, market conditions, industry trends and other information that we believe to be reasonable under the circumstances. We can make no assurance that actual results will conform to our estimates and assumptions; reported results of operations may be materially affected by changes in these estimates and assumptions. A detailed discussion of our critical accounting estimates is included in our Critical Accounting Estimates section in Item 7 of our December 31, 2025 report on Form 10-K.

Management considers the following accounting estimates to be critical because they involve significant judgment by management and those judgments could result in a material effect on our financial statements:

•Reserve for losses and loss adjustment expenses

•Reinsurance

•Valuation of investments and impairment of securities

•Income taxes

Estimation of Taxes

For interim periods, we generally utilize the estimated annual effective tax rate method under which we determine our provision (benefit) for income taxes based on the current estimate of our annual effective tax rate. For the three months ended March 31, 2026 and March 31, 2025, we utilized the estimated annual effective tax rate method. Under this method, items which are unusual, infrequent or that cannot be reliably estimated are considered in the effective tax rate in the period in which the item is included in income and are referred to as discrete items. See further discussion on this method in Note 4 of the Notes to Condensed Consolidated Financial Statements.

Liquidity and Capital Resources and Financial Condition

Overview

ProAssurance Corporation is a holding company and is a legal entity separate and distinct from its subsidiaries. As a holding company, our principal source of external revenue is our investment revenues. In addition, dividends from our operating subsidiaries represent another source of funds for our obligations, including debt service. We also charge our core domestic operating subsidiaries within our Specialty P&C and Workers' Compensation Insurance segments a management fee based on the extent to which services are provided to the subsidiary and the amount of gross premium written by the subsidiary. At March 31, 2026, we held cash and liquid investments of approximately $143 million outside our insurance subsidiaries that were available for use without regulatory approval or other restriction. As of May 1, 2026, we also have an additional $125 million in permitted borrowings available under our Revolving Credit Agreement as well as the possibility of a $50 million accordion feature, if successfully subscribed, as discussed in this section under the heading "Debt."

Our operating subsidiaries have not paid us any dividends during 2026. In the aggregate, our insurance subsidiaries are permitted to pay dividends of approximately $164 million over the remainder of 2026 without prior approval of state insurance regulators. However, the payment of any dividend requires prior notice to the insurance regulator in the state of domicile, and

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the regulator may reduce or prevent the dividend if, in its judgment, payment of the dividend would have an adverse effect on the surplus of the insurance subsidiary. We make the decision to pay dividends from an insurance subsidiary based on the capital needs of that subsidiary and may pay less than the permitted dividend or may also request permission to pay an additional amount (an extraordinary dividend). Currently we do not expect to pay dividends in 2026 prior to the closing of the proposed merger transaction with The Doctors Company.

Cash Flows

Cash flows between periods compare as follows:

Three Months Ended March 31
(In thousands)20262025Change
Net cash provided by (used in):
Operating activities$(21,323)$(11,609)$(9,714)
Investing activities4,3914,110281
Financing activities(5,508)(3,841)(1,667)
Increase (decrease) in cash and cash equivalents$(22,440)$(11,340)$(11,100)

The principal components of our operating cash flows are the excess of premiums collected and net investment income over losses paid and operating costs, including income taxes. Timing delays exist between the collection of premiums and the payment of losses associated with the premiums. Premiums are generally collected within the twelve-month period after the policy is written, while our claim payments are generally paid over a more extended period of time. Likewise, timing delays exist between the payment of claims and the collection of any associated reinsurance recoveries.

Operating cash flows decreased for the three months ended March 31, 2026 as compared to the three months ended March 31, 2025. The change in operating cash flows was primarily due to:

•A decrease in net premium receipts of $15.5 million primarily driven by a lower volume of written premium due to competitive market conditions as some competitors have chosen to write at a lower price and, to a lesser extent, an increase in premiums paid for reinsurance due to the 100% quota share reinsurance agreement with the third party that purchased the renewal rights related to our legal professional liability book of business during the second quarter of 2025.

•An increase in paid losses of $14.7 million driven by our Specialty P&C segment which reflected a decrease in cash received from reinsurance recoveries due to the payment of four large claims in the first quarter of 2025 as well as an increase in the volume of mid-sized claims as compared to the prior year period.

•A $2.2 million gain on the sale of our Franklin, TN property to an unrelated third party during the first quarter of 2025.

The decrease in operating cash flows was partially offset by:

•A decrease in cash paid for operating expenses of $18.3 million driven by lower incentive based compensation and transaction-related costs associated with the proposed merger transaction with The Doctors Company (see Note 1 of the Notes to the Condensed Consolidated Financial Statements).

•An increase in cash received from investment income of $3.5 million driven by higher average book yields as we take advantage of the current interest rate environment as our portfolio matures and an increase in distributed earnings and redemptions from our portfolio of investments in LPs/LLCs.

The remaining variance in operating cash flows for the three months ended March 31, 2026 as compared to the same period of 2025 was composed of individually insignificant components.

We manage our investing cash flows to ensure that we will have sufficient liquidity to meet our obligations, taking into consideration the timing of cash flows from our investments, including interest payments, dividends and principal payments, as well as the expected cash flows to be generated by our operations as discussed in this section under the heading "Investing Activities and Related Cash Flows."

Our financing cash flows are primarily comprised of repayment of debt as well as capital contributions received from or return of capital to external SPC participants. See further discussion of debt in this section under the heading "Financing Activities and Related Cash Flows."

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Operating Activities and Related Cash Flows

Reinsurance

Within our Specialty P&C segment, we use insurance and reinsurance (collectively, “reinsurance”) to provide capacity to write larger limits of liability, to provide reimbursement for losses incurred under the higher limit coverages we offer and to provide protection against losses in excess of policy limits. Within our Workers' Compensation Insurance segment, we use reinsurance to reduce our net liability on individual risks, to mitigate the effect of significant loss occurrences (including catastrophic events), to stabilize underwriting results and to increase underwriting capacity by decreasing leverage. In both our Specialty P&C and Workers' Compensation Insurance segments, we use reinsurance in risk sharing arrangements to align our objectives with those of our strategic business partners and to provide custom insurance solutions for large customer groups. The discussion in our Liquidity section under the same heading in Item 7 of our December 31, 2025 report on Form 10-K includes additional information regarding our reinsurance agreements.

Excess of Loss Reinsurance Agreements

Our MPL and Medical Technology Liability treaties renew annually on October 1 and our workers' compensation treaty renews annually on May 1. The significant coverages provided by our current excess of loss reinsurance agreements are depicted in the following table.

Current Excess of Loss Reinsurance Agreements

Column 1Column 2Column 3Column 4Column 5Column 6
Medical Professional LiabilityMedical Technology & Life Sciences ProductsWorkers' Compensation - Traditional

(1) Effective October 1, 2025, total reinsured limits decreased to $19M from $24M. Since we were not writing policies with these higher limits of coverage, the reduction in limit is not significant. One prepaid limit reinstatement of $16M and a second limit reinstatement of up to $16M for the second layer, subject to reinstatement premium, which attaches after the first reinstatement has been completely exhausted. Historically, the prepaid limit reinstatement and second limit reinstatement ranged from $16M to $21M. All limit reinstatements thereafter require no additional premium. Effective October 1, 2021, limits can be reinstated a maximum of four times.

(2) Prior to October 1, 2020, retention was $1M.

(3) Historically, retention has ranged from 0% to 32.5%.

(4) Historically, retention has ranged from $1M to $2M.

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(5) Subject to a limit of $20M per individual claimant. If an individua

[Excerpt truncated for page length; source filing is linked above.]

Latest 10-K MD&A

Extracted structurally from real Item 7 body heading to real Item 7A/8 boundary. Published MD&A gate trimmed front/tail over-capture. Confidence: high. Filing date: 2026-02-23. Report date: 2025-12-31.

ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

The following discussion generally focuses on the change in financial condition, results of operations and cash flows for the year ended December 31, 2025 as compared to the year ended December 31, 2024 and should be read in conjunction with the Consolidated Financial Statements and Notes to those statements which accompany this report. For a full discussion of the changes in the financial condition, results of operations and cash flows for the year ended December 31, 2024 as compared to the year ended December 31, 2023, please refer to Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" section of ProAssurance's December 31, 2024 report on Form 10-K.

The discussion contains certain forward-looking information that involves significant risks, assumptions and uncertainties. As discussed under the heading "Caution Regarding Forward-Looking Statements," our actual financial condition and results of operations could differ significantly from these forward-looking statements.

ProAssurance Overview

ProAssurance Corporation is a holding company for property and casualty insurance companies. Our insurance subsidiaries provide medical professional liability insurance, liability insurance for medical technology and life sciences risks and workers' compensation insurance.

During the first quarter of 2025, we altered our internal management reporting structure and the financial results evaluated by our CODM; therefore, we changed the composition of our operating and reportable segments to align with how the CODM currently oversees the business, allocates resources and evaluates operating performance. As a result, we now report the financial results of our subsidiary IAO, Inc. d/b/a ProAssurance Agency in the Specialty P&C segment which were previously reported in the Corporate segment. We operate in four segments: Specialty P&C, Workers' Compensation Insurance, Segregated Portfolio Cell Reinsurance and Corporate. All prior period segment information has been recast to conform to the current period presentation. The change in presentation had no impact on previously reported consolidated financial results.

Additional information on our four operating and reportable segments is included in Note 15 of the Notes to Consolidated Financial Statements, Part I and in the Segment Results sections herein that follow.

Growth Opportunities and Outlook

Given the cyclical nature of our insurance operations, our financial objectives span multiple years and we target a dynamic long-term ROE of 700 basis points above the 10-year U.S. Treasury rate, which at December 31, 2025 was approximately 11.2%. To achieve our long-term ROE target, we emphasize rate adequacy, selective underwriting, use of our proprietary data and predictive analytics, effective claims management, operational efficiency gained by leveraging our scope and scale, continued investment in technology-based solutions and prudent investment management. We may forego growth in favor of improving profitability, given our focus on rate adequacy and the competitive markets in which we operate. Our overall investment strategy is to focus on maximizing current income from our investment portfolio while maintaining appropriate credit risk, liquidity, duration and portfolio diversification.

On March 19, 2025, we entered into an Agreement and Plan of Merger (the “Merger Agreement”) with The Doctors Company, a California-domiciled reciprocal inter-insurance exchange, and Jackson Acquisition Corporation, a Delaware corporation and a wholly owned subsidiary of The Doctors Company (“Merger Sub”), pursuant to which, on the terms and subject to the conditions set forth in the Merger Agreement, Merger Sub will merge with and into ProAssurance (the “Merger”). ProAssurance will continue as the surviving corporation in the Merger as a wholly owned subsidiary of The Doctors Company.

We believe that this transaction will deliver significant value to our shareholders. Both ProAssurance and The Doctors Company were founded by physicians in response to the medical liability crisis of the 1970s. Both companies have grown over the years through business combinations with other physician-founded companies. This shared history has helped both companies fulfill our shared mission to protect others and given us similar operating philosophies and cultures. Bringing the strengths and capabilities of our companies together will allow our teams to continue to serve today’s healthcare providers with the necessary scale and breadth of capabilities.

On June 24, 2025, ProAssurance held a special meeting of stockholders (the “ProAssurance Special Meeting”) at which holders of ProAssurance’s common stock approved each of the proposals voted on at the ProAssurance Special Meeting relating to the transactions contemplated by the Merger Agreement. On July 2, 2025, the U.S. Federal Trade Commission granted early termination of the waiting period under the Hart-Scott Rodino Antitrust Improvements Act of 1976 with respect to the Merger.

The closing of the proposed Merger is subject to other customary closing conditions, including approval from insurance regulators in the jurisdictions where the Company’s operating subsidiaries are domiciled. As of February 23, 2026, The Doctors Company has received final approval from insurance regulators in Alabama, the District of Columbia, Illinois, Missouri, Texas

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and Vermont. Review of the proposed Merger by insurance regulators remains pending in California and Pennsylvania. The Company has also obtained final approval from Lloyd’s of London with respect to PRA Corporate Capital Ltd., and from the Cayman Islands Monetary Authority with respect to Inova Re and Eastern Re, each of which is a licensed entity in the Cayman Islands. The timing for completion of the pending reviews is uncertain and not within the Company’s control, but in light of progress made toward satisfaction of closing conditions, at the time of this filing, the Company continues to anticipate closing the transaction by June 30, 2026.

Our Specialty P&C segment includes our MPL insurance operations, which represent the largest product line in our consolidated gross premiums written (71% in 2025). The healthcare market in the U.S. is continuing to consolidate, which brings competitive challenges and opportunities. This consolidation initially took the form of hospitals acquiring physician practices and later the growth of physician groups owned by outside investors. As these trends continue, most physicians no longer practice medicine as owners of an independent practice. Large single and multi-specialty practices often operate in many states. Healthcare delivery settings are changing with the growth of retail delivery by advanced practice healthcare professionals as well as physicians practicing in distributed clinics, pharmacies, large consumer stores and online. The shifts within the healthcare settings continue to impact the overall market for medical professional liability products due to their differing risk profiles. We are focused on serving those segments of the market where we believe we can achieve our profitability objectives over time. In addition, we face consolidation within the distribution system, requiring us to adapt to fewer, larger intermediaries.

Over the past several years, we have also responded to rising severity in the medical professional liability market, driven by social inflation and eroding tort reforms that have been adversely affecting the loss environment. We believe we have stayed ahead of many in the space in achieving rate levels in MPL that outpace severity trends, achieving a cumulative premium change of more than 80% since 2018 in the medical professional liability market. We also continue to forgo renewal and new business opportunities in this loss environment that we believe do not meet our expectation of rate adequacy. As a result, retention of existing insureds remains under pressure as competitors in selected markets continue to be willing to write business at rate levels we believe are insufficient in this loss environment.

Along with our pricing actions, we remain focused on disciplined underwriting and managing claims to address these market conditions. Innovation tools also continue to enhance our risk selection, pricing decisions and workflows. Work is ongoing to maximize the use of predictive analytics to leverage our extensive data and to identify specific geographic markets and specialty sub-sectors where there are opportunities to write business that has the potential to meet our profitability objectives. We are also committed to ensuring that our insured and distribution partners find us easy to do business with - helping distinguish us in the marketplace.

Our Specialty P&C segment also includes medical technology liability insurance, which contributed 4% to consolidated gross premiums written in 2025. It is less affected by the trends impacting the healthcare sector and has the potential to increase its market share over time, although we may see slower growth if investments in healthcare-related research declines due to federal policy changes.

Our second largest product line is workers' compensation insurance which represents 23% of our consolidated gross premiums written in 2025, including alternative market premiums, which are eliminated in consolidation. The workers’ compensation market is highly competitive and multi-line insurers continue to leverage workers’ compensation in their product offerings, which has resulted in a reduction of new business writings. Our workers' compensation product offerings are designed to provide flexibility in offering solutions to our customers at a competitive price; however, the rates we charge our policyholders remain pressured by the continuation of loss cost decreases in the states within our operating territories, and most states in which we operate have approved additional loss cost decreases for 2026. We have observed higher than expected loss trends in our average cost per claim, which we primarily attributed to increased medical costs driven by wage inflation and medical advancements. In response, we have implemented various medical cost management initiatives in 2025 to address medical cost severity. These initiatives are intended to enhance medical outcomes for injured workers, improve our case reserve estimation capabilities and lighten the administrative burdens of our claims professionals. The initiatives include the utilization of a medical document intelligence platform that assists with directing care to best-performing providers to help identify high severity claims early in the in claims' life cycle. Since implementing these initiatives, we have observed improvements in the average medical cost per claim, the benefit of which was more than offset by higher severity trends (see discussion that follows in Critical Accounting Estimates under the heading "Reserve for Losses and Loss Adjustment Expenses").

We believe our focus on our organization's Mission, Vision and Core Values enhances our market position and differentiates us from other insurers. We will continue to uphold our values of integrity, leadership, relationships and enthusiasm in all of our activities. We will honor these values in the performance of our Mission and pursuit of our Vision. We believe a commitment to our Mission and Vision in the service of our customers will continue to improve retention and add new insureds.

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Key Performance Measures

We are committed to disciplined underwriting, pricing and loss reserving practices as well as strategically managing our investment portfolio. We are also committed to maintaining prudent operating and financial leverage. We recognize the importance that our customers and producers place on the financial strength of our insurance subsidiaries, and we manage our business to protect our financial security.

In evaluating our performance, we consider a number of performance measures, including the following:

•The operating ratio which is calculated as net losses and loss adjustment expenses incurred plus underwriting, policy acquisition and operating expenses incurred less net investment income divided by net premiums earned (the combined ratio less the investment income ratio). This ratio provides the combined effect of underwriting profitability and investment income.

•The net loss ratio which is calculated as net losses and loss adjustment expenses incurred divided by net premiums earned and is a component of underwriting profitability.

•The underwriting expense ratio which is calculated as underwriting, policy acquisition and operating expenses incurred divided by net premiums earned and is a component of underwriting profitability.

•The combined ratio which is the sum of the net loss ratio and the underwriting expense ratio and measures underwriting profitability.

•The investment income ratio which is calculated as net investment income divided by net premiums earned and measures the contribution investment earnings provide to our overall profitability.

•The effective tax rate which is calculated as total income tax expense (benefit) divided by income (loss) before income taxes.

•Non-GAAP operating income (loss) which is widely used to evaluate performance within the insurance sector. In calculating Non-GAAP operating income (loss), we exclude the effects of items that do not reflect normal operating results. We believe Non-GAAP operating income (loss) presents a useful view of the performance of our ongoing core insurance operations; however, it should be considered in conjunction with net income (loss) computed in accordance with GAAP. See a reconciliation to its GAAP counterpart in the Executive Summary of Operations section under the heading “Non-GAAP Financial Measures” that follows.

•ROE which is calculated as net income (loss) divided by the average of beginning and ending total shareholders’ equity. This ratio measures our overall after-tax profitability and shows how efficiently capital is being used.

•Non-GAAP operating ROE which is calculated as Non-GAAP operating income (loss) divided by the average of beginning and ending total shareholders’ equity. Non-GAAP operating ROE measures the overall after-tax profitability of our ongoing core insurance operations and shows how efficiently capital is being used; however, it should be considered in conjunction with ROE computed in accordance with GAAP. See a reconciliation to its GAAP counterpart in the Executive Summary of Operations section under the heading “Non-GAAP Financial Measures” that follows.

•Book value per share which is calculated as total GAAP shareholders’ equity divided by the total number of common shares outstanding at the balance sheet date. This ratio measures the net worth of the Company to shareholders on a per-share basis. Growth in book value per share is an indicator of overall profitability.

•Non-GAAP adjusted book value per share which is a Non-GAAP measure widely used within the insurance sector and is calculated as total shareholders’ equity, excluding AOCI, divided by the total number of common shares outstanding at the balance sheet date. This Non-GAAP calculation measures the net worth of the Company to shareholders on a per share basis excluding AOCI to eliminate the temporary and potentially significant effects of fluctuations in interest rates on our fixed income portfolio; however, it should be considered in conjunction with book value per share computed in accordance with GAAP. See a reconciliation to its GAAP counterpart in the Executive Summary of Operations section under the heading “Non-GAAP Financial Measures” that follows.

In particular, we focus on our combined ratio and investment returns, both of which directly affect our ROE, operating ratio and growth in our book value per share.

Critical Accounting Estimates

Our Consolidated Financial Statements are prepared in conformity with GAAP. Preparation of these financial statements requires us to make estimates and assumptions that affect the amounts we report on those statements. We evaluate these estimates and assumptions on an ongoing basis based on current and historical developments, market conditions, industry trends and other information that we believe to be reasonable under the circumstances. We can make no assurance that actual results

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will conform to our estimates and assumptions; reported results of operations may be materially affected by changes in these estimates and assumptions.

Management considers the following accounting estimates to be critical because they involve significant judgment by management and those judgments could result in a material effect on our financial statements.

Reserve for Losses and Loss Adjustment Expenses

The largest component of our liabilities is our reserve for losses and loss adjustment expenses ("reserve for losses" or "reserve"), and the largest component of expense for our operations is incurred losses and loss adjustment expenses (also referred to as “losses and loss adjustment expenses,” “incurred losses,” “losses incurred” and “losses”). Incurred losses reported in any period reflect our estimate of losses incurred related to the premiums earned in that period as well as any changes to our previous estimate of the reserve required for prior periods.

As of December 31, 2025, our reserve is comprised almost entirely of long-tail exposures. The estimation of long-tailed losses is inherently complex and is subject to significant judgment on the part of management. Due to the nature of our claims, our loss costs, even for claims with similar characteristics, can vary significantly depending upon many factors, including but not limited to the specific characteristics of the claim and the manner or jurisdiction in which the claim is resolved. Long-tailed insurance is characterized by the extended period of time typically required both to assess the viability of a claim and potential damages, if any, and to reach a resolution of the claim. The claims resolution process may extend to more than five years. The combination of continually changing conditions and the extended time required for claim resolution results in a loss cost estimation process that requires actuarial skill and the application of significant judgment, and such estimates require periodic modification.

Our reserve is established by management after taking into consideration a variety of factors including premium rates, historical paid and incurred loss development trends and our evaluation of the current loss environment including frequency, severity, expected effects of inflation (monetary, social and medical), general economic and social trends, and the legal and political environment. We also take into consideration the conclusions reached by our internal and consulting actuaries. We update and review the data underlying the estimation of our reserve for losses each reporting period and make adjustments to loss estimation assumptions that we believe best reflect emerging data. Both our internal and consulting actuaries perform an in-depth review of our reserve for losses on at least a semi-annual basis using the loss and exposure data of our insurance subsidiaries.

We partition our reserves by accident year, which is the year in which the claim becomes our liability. For claims-made policies, the insured event generally becomes a liability when the event is first reported to us. For occurrence policies, the insured event becomes a liability when the event takes place. For retroactive coverages, the insured event becomes a liability at inception of the underlying contract. As claims are incurred (reported) and claim payments are made, they are aggregated by accident year for analysis purposes. We also partition our reserves by reserve type: case reserves and IBNR reserves. Case reserves are established by our claims departments based upon the particular circumstances of each reported claim and represent our estimate of the future loss costs (often referred to as expected losses) that will be paid on reported claims. Case reserves are decremented as claim payments are made and are periodically adjusted upward or downward as estimates regarding the amount of future losses are revised; reported loss for an individual claim is the case reserve at any point in time plus the claim payments that have been made to date. IBNR reserves are estimated by accident year by our actuarial department and represent our estimate in the aggregate of future development on losses that have been reported to us and our estimate of losses that have been incurred but not reported to us.

Our reserving process can be broadly grouped into three areas: the establishment of the reserve for the current accident year (the initial reserve), the re-estimation of the reserve for prior accident years (development of prior accident years) and the establishment of the initial reserve for risks assumed in business combinations, applicable only in periods in which acquisitions occur (the acquired reserve). A summary of the activity in our net reserve for losses during 2025 and 2024 is provided under the heading "Losses" in the Liquidity and Capital Resources and Financial Condition section that follows.

Current Accident Year - Initial Reserve

Considerable judgment is required in establishing our initial reserve for any current accident year period, as there is limited data available upon which to base our estimate (see further discussion that follows under the heading "Use of Judgment"). Our process for setting an initial reserve considers the unique characteristics of each product, but in general we rely heavily on the loss assumptions that were used to price business, as our pricing reflects our analysis of loss costs that we expect to incur relative to the insurance product being priced.

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Specialty P&C Segment. Loss costs within this segment are impacted by many factors including but not limited to the nature of the claim, including whether or not the claim is an individual or a mass tort claim, the personal situation of the claimant or the claimant's family, the outcome of jury trials including the impacts of social inflation, the legislative and judicial climate where any potential litigation may occur, general economic and social trends and the trend of healthcare costs. Within our Specialty P&C segment, for our Medical Professional Liability business (86% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2025), we set an initial reserve using a loss ratio approach based upon our evaluation of the current loss environment including frequency, severity, monetary inflation, social inflation and legal trends. See further discussion in our Segment Results - Specialty Property & Casualty section that follows under the heading "Losses and Loss Adjustment Expenses."

The risks insured in our Medical Technology Liability business (3% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2025) are more varied, and policies are individually priced based on the risk characteristics of the policy and the account. The insured risks range from startup operations to large multinational entities, and the larger entities often have significant deductibles or self-insured retentions. Reserves are established using our most recently developed actuarial estimates of losses expected to be incurred based on factors which include results from prior analysis of similar business, industry indications, observed trends and judgment. Claims in this line of business primarily involve bodily injury to individuals and are affected by factors similar to those of our MPL line of business. For the Medical Technology Liability business, we also establish an initial reserve using a loss ratio approach, including a provision in consideration of historical loss volatility that this line of business has exhibited.

Workers' Compensation Insurance Segment. Many factors affect the ultimate losses incurred for our workers' compensation coverages (6% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2025) including but not limited to the type and severity of the injury, the age, health and occupation of the injured worker, the estimated length of disability, medical treatment and related costs, and the jurisdiction and workers' compensation laws of the state of the injury occurrence.

We use various actuarial methodologies in developing our workers’ compensation reserve, combined with a review of the payroll exposure base. For the current accident year, given the lack of seasoned information, the different actuarial methodologies produce results with significant variability; therefore, more emphasis is placed on supplementing results from the actuarial methodologies with trends in exposure base, medical expense inflation, general inflation, severity and claim counts, among other things, to select an ultimate loss indication.

Segregated Portfolio Cell Reinsurance Segment. The factors that affect the ultimate losses incurred for the workers' compensation and medical professional liability coverages assumed by the SPCs at Inova Re and Eastern Re (2% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2025) are consistent with that of our Workers’ Compensation Insurance and Specialty P&C segments, respectively.

Development of Prior Accident Years

In addition to setting the initial reserve for the current accident year, we reassess the amount of reserve required for prior accident years each period.

The foundation of our reserve re-estimation process is an actuarial analysis that is performed by both our internal and consulting actuaries. This detailed analysis projects ultimate losses based on partitions which include line of business, geography, coverage layer and accident year. The procedure uses the most representative data for each partition, capturing its unique patterns of development and trends. We believe that the use of consulting actuaries provides an independent view of our loss data as well as a broader perspective on industry loss trends.

The analyses performed by our internal actuarial team and the consulting actuaries analyzes each partition of our business in a variety of ways and uses multiple actuarial methodologies in performing these analyses, including:

•Bornhuetter-Ferguson (Paid and Reported) Method

•Paid Development Method

•Reported (Incurred) Development Method

•Average Paid Value Method

•Average Reported Value Method

A brief description of each method follows.

Bornhuetter-Ferguson Method. We use both the Paid and the Reported Bornhuetter-Ferguson Methods. The Paid Method assigns partial weight to initial expected losses for each accident year (initial expected losses being the first established case and IBNR reserves for a specific accident year) and partial weight to paid to date losses. The Reported Method assigns partial weight to the initial expected losses and partial weight to current reported losses. The weights assigned to the initial expected losses decrease as the accident year matures.

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Paid Development and Reported (Incurred) Development Methods. These methods use historical, cumulative losses (paid losses for the Paid Development Method, reported losses for the Reported (Incurred) Development Method) by accident year and develop those actual losses to estimated ultimate losses based upon the assumption that each accident year will develop to estimated ultimate cost in a manner that is analogous to prior years, adjusted as deemed appropriate for the expected effects of known changes in the claim payment environment (and case reserving environment for the Reported (Incurred) Development Method); and to the extent necessary, supplemented by analyses of the development of broader industry data.

Average Paid Value and Average Reported Value Methods. In these methods, average claim cost data (paid claim cost for the Average Paid Value Method and reported claim cost for the Reported Value Method) is developed to an ultimate average cost level by report year based on historical data. Claim counts are similarly developed to an ultimate count level. The average claim cost (after rounding and adjustment, if necessary, to accommodate report year data that is not considered to be predictive) is then multiplied by the ultimate claim counts by report year to derive ultimate loss and ALAE.

We use various actuarial methods in the process of setting reserves. Each actuarial method generally returns a different value, and for the more recent accident years the variations among the different methodologies can be significant. Generally, methods such as the Bornhuetter-Ferguson Method are used on more recent accident years where we have less data on which to base our analysis. As time progresses and we have an increased amount of data for a given accident year, we begin to give more confidence to the development and average methods, as these methods typically rely more heavily on our own historical data. These methods emphasize different aspects of loss reserve estimation and provide a variety of perspectives for our decisions.

Certain of the methodologies utilized to estimate the ultimate losses for each partition of our reserves consider the actual amounts paid. Paid data is particularly influential when a large portion of known claims have been closed, as is the case for older accident years. In selecting a point estimate for each partition, management considers the extent to which trends are emerging consistently for all partitions and known industry trends. Thus, actual, rather than estimated severity trends are given more consideration. If actual severity trends are lower than those estimated at the time that reserves were previously established, the recognition of favorable development is indicated. This is particularly true for older accident years where our actuarial methodologies give more weight to actual loss costs (severity).

The various actuarial methods discussed above are applied in a consistent manner from period to period. For each partition of our reserves, we evaluate the results of the various methods, along with the supplementary statistical data regarding such factors as closed with and without indemnity ratios, claim severity trends, the expected duration of such trends, changes in the legal and legislative environment and the current economic environment to develop a point estimate based upon management's judgment and past experience. The series of selected point estimates is then combined to produce an overall point estimate for ultimate losses.

We utilize the selected point estimates of ultimate losses to develop estimates of ultimate losses recoverable from reinsurers, based on the terms and conditions of our reinsurance agreements. An overall estimate of the amount receivable from reinsurers is determined by combining the individual estimates. Our net reserve estimate is the gross reserve point estimate less the estimated reinsurance recovery.

For our Workers’ Compensation Insurance segment and for the workers' compensation exposures in our Segregated Portfolio Cell Reinsurance segment, we utilize the Reported (Incurred) Development Method, Paid Development Method and Bornhuetter-Ferguson Method, to develop our reserve for each accident year. The actuarial review includes the stratification of claims data (lost time claims, medical only claims) using different variations that allow us to identify trends that may not be readily identifiable if the data was evaluated only in the aggregate. Reported and paid loss development factors are key assumptions in the reserve estimation process and are influenced by our historical reported and paid loss development patterns. As accident years mature, the various actuarial methodologies produce more consistent loss estimates.

Acquired Reserve

The acquisition of NORCAL on May 5, 2021 increased our gross reserves by $1.2 billion which was the fair value of NORCAL's gross loss reserve at the time of acquisition. The fair value estimate of NORCAL's gross reserve for losses and loss adjustment expenses was based on three components: an actuarial estimate of the expected future net cash flows, a reduction to those cash flows for the time value of money determined utilizing the U.S. Treasury Yield Curve and a risk margin adjustment to reflect the net present value of profit that an investor would demand in return for the assumption of the development risk associated with the reserve. The fair value of NORCAL's gross reserve, including the risk margin adjustment, exceeded the actuarial estimate of NORCAL’s undiscounted gross loss reserve by approximately $42.2 million as of May 5, 2021. This fair value adjustment was recorded to the reserve for losses and loss adjustment expenses and will be amortized over a period utilizing loss payment patterns as a reduction to prior accident year net losses and loss adjustment expenses. We also recorded other adjustments to NORCAL’s reserve as a result of purchase accounting including negative VOBA on NORCAL’s assumed unearned premium and assumed DDR reserve.

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Use of Judgment/Variability of Loss Reserves

The process of estimating reserves involves a high degree of judgment and is subject to a number of variables. These variables can be affected by both views of internal and external events, such as changes in views of monetary and social inflation, legal trends and legislative changes, as well as differentiating views of individuals involved in the reserve estimation process, among others. We continually refine our estimates in a regular, ongoing process as historical loss experience develops and additional claims are reported and settled. Our objective is to consider all significant facts and circumstances known at the time.

Our loss reserves may be impacted by social inflation, which is generally described as the rising costs of insurance claims resulting from factors including, but not limited to, increasing litigation, broader definitions of liability, more plaintiff-friendly legal decisions, jury behavior, third-party litigation financing, and larger compensatory jury awards and non-economic damages. These factors could lead to greater than anticipated claims and claim handling expenses which could exceed our established reserves causing us to increase our loss reserves.

The effects of monetary and medical inflation could cause the cost of claims to rise in the future. Our loss reserves include assumptions about future payments for settlement of claims and claims handling expenses, such as medical treatments and litigation costs. For our workers' compensation reserves, healthcare wage inflation and medical advancements may also increase the cost of claims. To the extent inflation causes these costs to increase above reserves established for these claims, we will be required to increase our loss reserves with a corresponding reduction in our financial results in the period in which the need for additional reserves is identified.

MPL. Over the past several years the most influential factor affecting the analysis of our MPL reserves and the related development recognized has been an observed increase in claim severity for the broader medical professional liability industry as well as higher initial loss expectations on incurred claims. The severity trend is an explicit component of our pricing models and directly impacts the reserving process. Our estimate of this trend and our expectations about changes in this trend impact a variety of factors, from the selection of expected loss ratios to the ultimate point estimates established by management.

Because of the implicit and wide-ranging nature of severity trend assumptions on the loss reserving process, it is not practical to specifically isolate the impact of changing severity trends. However, because severity is an explicit component of our MPL pricing process we can better isolate the impact that changing severity can have on our loss costs and loss ratios in regards to our pricing models for this business component. Our current MPL pricing models assume severity trends in the range of 3% to 5% depending on state, territory and specialty. In some portions of our MPL business, we have observed and reflected higher severity trends in our estimates of losses and loss adjustment expenses.

Due to the long-tailed nature of our claims and the previously discussed historical volatility of loss costs, selection of a severity trend assumption is a subjective process that is inherently likely to prove inaccurate over time. Given the long tail and volatility, we are generally cautious in making changes to the severity assumptions within our pricing models. All open claims and accident years are generally impacted by a change in the severity trend, which compounds the effect of such a change.

Although the future degree and impact of the ultimate severity trend remains uncertain due to the long-tailed nature of our business, we have given consideration to observed loss costs in setting our rates. For our MPL business, this practice has recently resulted in rate increases reflecting the rising loss cost environment, and we anticipate further renewal pricing increases due to increasing loss severity.

Workers' Compensation. In our workers’ compensation business, severity is not an explicit component of our pricing process, as loss costs are established by the states in which we operate. We do, however, have the ability in certain states to apply for increases in our loss cost multipliers to adjust for company specific loss experience that is higher than state loss cost changes. In our reserving process, we consider the loss severity trends in evaluating both our current and expected loss development. Historically, we have been able to minimize the impact of higher severity trends as a result of our early intervention and case management strategies in our claims process, which results in claims being resolved more quickly than the industry norm. In the second half of 2023 and throughout 2024, we observed higher than expected loss trends in our average cost per claim, which we primarily attributed to increased medical costs driven by wage inflation and medical advancements. We implemented various medical cost management initiatives during 2025 to address the medical cost severity and we have observed improvements in the average medical cost per claim. However, an increase in severity-related claim activity on large losses more than offset medical cost savings related to these initiatives. In response to this trend, we increased our full year current accident year net loss ratio from 75% at September 30, 2025 to 77% at December 31, 2025.

As previously noted, the number of data points and variables considered and the subjective process followed in establishing our loss reserve makes it impractical to isolate individual variables and demonstrate their impact on our estimate of loss reserves. However, to provide a better understanding of the potential variability in our reserves, we have modeled implied reserve ranges around our single point net reserve estimates for our various lines of business assuming different confidence levels. The ranges have been developed by aggregating the expected volatility of losses across partitions of our business to

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obtain a consolidated distribution of potential reserve outcomes. The aggregation of this data takes into consideration correlations among our geographic and specialty mix of business. The result of the correlation approach to aggregation is that the ranges are narrower than the sum of the ranges determined for each partition.

We have used this modeled statistical distribution to calculate an 80% and 60% confidence interval for the potential outcome of our consolidated net reserve for losses. The high and low end points of the distributions are as follows:

Low End PointCarried Net ReserveHigh End Point
80% Confidence Level$1.994 billion$2.684 billion$3.489 billion
60% Confidence Level$2.179 billion$2.684 billion$3.137 billion

Any change in our estimate of net ultimate losses for prior years is reflected in net income (loss) in the period in which such changes are made. Due to the size of our consolidated reserve for losses and the large number of claims outstanding at any point in time, even a small percentage adjustment to our total reserve estimate could have a material effect on our results of operations for the period in which the adjustment is made.

Loss Development by Line of Business

Professional Liability

Our professional liability business is primarily comprised of our MPL line of business and, to a lesser extent, our legal professional liability business which is currently in run-off. As a result of the higher severity environment in our MPL line of business, we saw our closed-with-indemnity-payment ratio (i.e., the number of suits closed with an indemnity or loss payment as compared to the total number of closed suits) for our claims increase from 28% in 2015 to 35% in 2025.

The following table presents additional information about the loss development for our professional liability business, excluding loss development for MPL coverages assumed by the SPCs at Inova Re and Eastern Re. Furthermore, loss development for our professional liability business for the years ended December 31, 2025, 2024 and 2023 excludes the amortization of purchase accounting fair value adjustments.

($ in thousands)202520242023
Accident YearsEstimated Ultimate Losses, Net of Reinsurance, December 31, 2025Reserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims Closed
2025$596,065N/A24.1%N/AN/AN/AN/A
2024$584,618$74151.9%N/A24.5%N/AN/A
2023$655,621$12,25270.1%$6,14652.7%N/A24.7%
2022$598,959$(14,797)81.9%$(1,362)70.8%$(10,151)55.0%
2021$659,679$(18,128)87.8%$(10,207)82.1%$(11,690)71.6%
2020$841,423$(26,805)93.0%$(14,686)89.3%$44,06182.5%
2019$855,393$(20,215)96.0%$(3,536)93.7%$5,22090.4%
2018$851,417$(1,261)97.3%$2,78296.3%$41393.6%
2017$717,217$(1,156)98.7%$2,27396.5%$(8,265)95.4%
2016$728,729$(7,277)98.2%$(2,555)91.7%$(2,922)92.3%
Prior to 2016$13,823,916$1,746$(12,781)$(7,057)

•We recognized net favorable reserve development of $74.9 million during the year ended December 31, 2025 primarily due to lower than expected loss emergence principally related to accident years 2019 through 2022.

•Not included in the table above, is $3.4 million, $5.3 million and $8.3 million of amortization of the purchase accounting fair value adjustment on NORCAL's assumed net reserve and amortization of the negative VOBA associated with NORCAL's DDR reserve which is recorded as a reduction to prior accident year net losses and loss adjustment expenses in 2025, 2024 and 2023, respectively.

•Not included in the above table is $0.7 million of favorable development recognized in 2025 and $0.3 million and $1.3 million of unfavorable development recognized in 2024 and 2023, respectively, in our Segregated Portfolio Cell Reinsurance segment related to MPL coverages assumed by the SPCs at Inova Re and Eastern Re, as previously discussed.

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Medical Technology Liability

The nature of the risks insured and volatility of the loss experience in the Medical Technology Liability line of business has produced more variable loss development, as presented in the following table:

($ in thousands)202520242023
Accident YearsEstimated Ultimate Losses, Net of Reinsurance, December 31, 2025Reserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims Closed
2025$18,630N/A41.1%N/AN/AN/AN/A
2024$19,011$42477.4%N/A49.8%N/AN/A
2023$12,517$(4,738)72.8%$(1,609)55.3%N/A28.0%
2022$11,670$(2,424)89.6%$(2,141)80.2%$(1,448)59.6%
2021$11,316$(2,018)82.2%$83677.2%$(1,647)73.0%
2020$9,697$(332)86.7%$(1,098)84.0%$(1,442)80.1%
2019$13,501$97363.3%$(953)62.2%$1,23561.3%
2018$8,081$(1,158)90.4%$18689.5%$49989.5%
2017$6,668$(178)99.0%$(65)99.0%$(1,056)99.0%
2016$8,436$(366)100.0%$17399.5%$(517)99.5%
Prior to 2016$614,610$(184)$171$377

•Approximately $9.2 million of the $10.0 million total net favorable development recognized in 2025 related to the 2021 through 2023 accident years. The development for the 2021 through 2023 accident years represents a 20.5% reduction to the ultimates established for those reserves at December 31, 2024.

•In 2025, 2024 and 2023, the development was largely attributable to favorable results from claims closed during the year. As time has elapsed we have recognized that actual loss experience has on average been better than estimated. We have been cautious in recognizing the improvement, but as claims have matured and claims are closed or have become more certain for the remaining open claims, we have revised reserve estimates. We believe the need for a cautious approach is required as outcomes are uncertain and results can be significantly affected by outcomes for a small number of cases.

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Workers' Compensation

Claims in our workers’ compensation line of business have historically closed at a faster rate than in our MPL or Medical Technology Liability lines of business. This faster disposition rate, along with a lower net retention after the application of reinsurance, has resulted in less volatility in loss estimates on a net basis. However, a change in the number of individually-severe claims can create volatility in a given accident year. The following table presents additional information about the loss development for our workers' compensation line of business, excluding changes in the AAD liability in our Workers' Compensation Insurance segment as it is not attributable to a specific accident year:

($ in thousands)202520242023
Accident YearsEstimated Ultimate Losses, Net of Reinsurance, December 31, 2025Reserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims Closed
2025$143,144N/A39.0%N/AN/AN/AN/A
2024$146,391$(4,565)80.4%N/A43.0%N/AN/A
2023$146,725$(1,268)91.8%$(1,576)79.5%N/A40.3%
2022$151,787$(16)95.4%$(116)91.3%$9,01681.3%
2021$144,693$(1,176)97.4%$(1,255)95.7%$1,21792.8%
2020$135,328$17298.8%$(255)98.2%$(2,318)96.7%
2019$146,155$(566)98.8%$(1,183)98.3%$(2,119)97.9%
2018$155,672$(395)99.0%$(1,266)98.5%$(1,819)98.1%
2017$125,034$(1)99.2%$(479)98.8%$(711)98.7%
2016$107,215$(23)99.2%$(13)99.1%$(231)99.0%
Prior to 2016$1,006,108$(1,098)$2,557$979

•In 2025, we recognized $1.8 million of net favorable development in our Workers' Compensation Insurance segment and we recognized $7.1 million of net favorable development in our Segregated Portfolio Cell Reinsurance segment related to workers' compensation business.

Reinsurance

We use insurance and reinsurance (collectively, “reinsurance”) to provide capacity to write larger limits of liability, to provide reimbursement for losses incurred under the higher limit coverages we offer, to provide protection against losses in excess of policy limits and, in the case of risk sharing arrangements, to align our objectives with those of our strategic business partners and to provide custom insurance solutions for large customer groups. The purchase of reinsurance does not relieve us from the ultimate risk on our policies; however, it does provide reimbursement for certain losses we pay.

We make a determination of the amount of insurance risk we choose to retain based upon numerous factors, including our risk tolerance and the capital we have to support it, the price and availability of reinsurance, the volume of business, our level of experience with a particular set of exposures and our analysis of the potential underwriting results. We purchase excess of loss reinsurance to limit the amount of risk we retain and we do so from a number of companies to mitigate concentrations of credit risk. As of December 31, 2025, there is no reinsurer, on an individual basis, for which our recoverables for both paid and unpaid claims (net of amounts due to the reinsurer) and our prepaid balances are more than $48 million, in the aggregate. We utilize reinsurance brokers to assist us in the placement of these reinsurance programs and in the analysis of the credit quality of our reinsurers. The determination of which reinsurers we choose to do business with is based upon an evaluation of their then current financial strength, rating, stability and claims payment practices.

We evaluate each of our ceded reinsurance contracts at inception to confirm that there is sufficient risk transfer to allow the contract to be accounted for as reinsurance under current accounting guidance. At December 31, 2025, all ceded contracts were accounted for as risk transferring contracts.

Our receivable from reinsurers on unpaid losses and loss adjustment expenses represents our estimate of the amount of our reserve for losses that will be recoverable under our reinsurance programs. We base our estimate of funds recoverable upon our expectation of ultimate losses and the portion of those losses that we estimate to be allocable to reinsurers based upon the terms and conditions of our reinsurance agreements. Our assessment of the collectability of the recorded amounts receivable from reinsurers considers the payment history of the reinsurer, publicly available financial and rating agency data, our interpretation of the underlying contracts and policies and responses by reinsurers.

Given the uncertainty inherent in our estimates of losses and related amounts recoverable from reinsurers, these estimates may vary significantly from the ultimate outcome.

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Under the terms of certain of our reinsurance agreements, the amount of premium that we cede to our reinsurers is based in part on the losses we recover under the agreements. Therefore, we make an estimate of premiums ceded under these reinsurance agreements subject to certain minimums and maximums. Any adjustments to our estimates of losses recoverable under our reinsurance agreements or the premiums owed under our agreements are reflected in current operations. Due to the size of our reinsurance balances, an adjustment to these estimates could have a material effect on our results of operations for the period in which the adjustment is made.

Our reinsurance receivables are exposed to credit losses but to date have not experienced any significant amount of credit losses. To partially mitigate our exposure to credit losses, reinsurance receivables totaling approximately $117.6 million were collateralized by letters of credit or funds withheld as of December 31, 2025. We measure expected credit losses on our reinsurance receivables on a collective basis when similar risk characteristics exist or on an individual basis if we determine a receivable does not share similar risk characteristics. We measure expected credit losses associated with our reinsurance receivables (related to both paid and unpaid losses) at the consolidated level as our reinsurance receivables share similar risk characteristics including type of financial asset, type of industry and similar historical and expected credit loss patterns. We measure expected credit losses over the average contractual term of our reinsurance receivables utilizing a loss rate method. Historical internal credit loss experience is the basis for our assessment of expected credit losses; however, we may also consider historical credit loss information from external sources. We also consider reasonable and supportable forecasts of future economic conditions in our estimate of expected credit losses. Expected credit losses associated with our reinsurance receivables (related to both paid and unpaid losses) were nominal in amount as of December 31, 2025 and 2024. No reinsurance balances were written off for credit reasons during the years ended December 31, 2025 or 2024. Should our expected credit loss analysis or other facts or circumstances lead us to believe that any reinsurer may not meet its obligations to us, adjustments to the allowance for expected credit losses or to reinsurance receivables would be reflected in current operations. Such an adjustment has the potential to be material to the results of operations in the period in which it is recorded; however, we would not expect such an adjustment to have a material effect on our capital position or our liquidity. For further information on our allowance for expected credit losses related to our receivables from reinsurers see Note 1 of the Notes to Consolidated Financial Statements.

Investment Valuations

We record the majority of our investments at fair value as shown in the table below. At December 31, 2025, the distribution of our investments based on GAAP fair value hierarchies (levels) was as follows:

Distribution by GAAP Fair Value Hierarchy
Level 1Level 2Level 3Not CategorizedTotal Investments
Investments recorded at:
Fair value7%83%2%5%97%
Other valuations3%
Total Investments100%

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. All of our fixed maturity and equity investments are carried at fair value. The fair value of our short-term securities approximates the cost of the securities due to their short-term nature.

Because of the number of securities we own and the complexity of developing accurate fair values, we utilize multiple independent pricing services to assist us in establishing the fair value of individual securities. The pricing services provide fair values based on exchange-traded prices, if available. If an exchange-traded price is not available, the pricing services, if possible, provide a fair value that is based on multiple broker/dealer quotes or that has been developed using pricing models. Pricing models vary by asset class and utilize currently available market data for securities comparable to ours to estimate a fair value for our securities. The pricing services scrutinize market data for consistency with other relevant market information before including the data in the pricing models. The pricing services disclose the types of pricing models used and the inputs used for each asset class. Determining fair values using these pricing models requires the use of judgment to identify appropriate comparable securities and to choose a valuation methodology that is appropriate for the asset class and available data.

The pricing services provide a single value per instrument quoted. We review the values provided for reasonableness each quarter by comparing market yields generated by the supplied value versus market yields observed in the marketplace. We also compare yields indicated by the provided values to appropriate benchmark yields and review for values that are unchanged or that reflect an unanticipated variation as compared to prior period values. We utilize a primary pricing service for each security type and compare provided information for consistency with alternate pricing services, known market data and information

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from our own trades, considering both values and valuation trends. We also review weekly trades versus the prices supplied by the services. If a supplied value appears unreasonable, we discuss the valuation in question with the pricing service and make adjustments if deemed necessary. Historically our review has not resulted in any material changes to the values supplied by the pricing services. The pricing services do not provide a fair value unless an exchange-traded price or multiple observable inputs are available. As a result, the pricing services may provide a fair value for a security in some periods but not others, depending upon the level of recent market activity for the security or comparable securities.

Level 1 Investments

Fair values for a majority of our equity securities and portions of our short-term and convertible securities are determined using exchange-traded prices. There is little judgment involved when fair value is determined using an exchange-traded price. In accordance with GAAP, we classify securities valued using an exchange-traded price as Level 1 securities.

Level 2 Investments

Most fixed income securities do not trade daily; thus, exchange-traded prices are generally not available for these securities. However, market information (often referred to as observable inputs or market data, including but not limited to, last reported trade, non-binding broker quotes, bids, benchmark yield curves, issuer spreads, two-sided markets, benchmark securities, offers and recent data regarding assumed prepayment speeds, cash flow and loan performance data) is available for most of our fixed income securities. We determine fair value for a large portion of our fixed income securities using available market information. In accordance with GAAP, we classify securities valued based on multiple market observable inputs as Level 2 securities.

Level 3 Investments

When a pricing service does not provide a value for one of our fixed maturity securities, management estimates fair value using either a single non-binding broker quote or pricing models that utilize market based assumptions which have limited observable inputs. The process involves significant judgment in selecting the appropriate data and modeling techniques to use in the valuation process. In accordance with GAAP, we classify securities valued using limited observable inputs as Level 3 securities.

Fair Values Not Categorized

We hold interests in certain investment funds, primarily LPs/LLCs, which measure fund assets at fair value on a recurring basis and provide us with a NAV for our interest. As a practical expedient, we consider the NAV provided to approximate the fair value of our interest. In accordance with GAAP, we do not categorize these investments within the fair value hierarchy.

Nonrecurring Fair Value Measurements

We measure the fair value of certain assets on a nonrecurring basis when events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. These assets include investments carried principally at cost, investments in tax credit partnerships, fixed assets, goodwill and other intangible assets. These assets would also include any equity method investments that do not provide a NAV. We did not have any assets or liabilities that were measured at fair value on a nonrecurring basis at December 31, 2025 or December 31, 2024.

Investments - Other Valuation Methodologies

Certain of our investments, in accordance with GAAP for the type of investment, are measured using methodologies other than fair value. At December 31, 2025, these investments represented approximately 3% of total investments and are detailed in the following table. Additional information about these investments is provided in Note 2 and Note 3 of the Notes to Consolidated Financial Statements.

(In millions)Carrying ValueGAAP Measurement Method
Other investments:
Other, principally FHLB capital stock$7.2Principally Cost
Investment in unconsolidated subsidiaries:
Investments in tax credit partnerships0.1Equity
Equity method investments, primarily LPs/LLCs31.0Equity
31.1
BOLI82.8Cash surrender value
Total investments - Other valuation methodologies$121.1

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Impairments

We evaluate our available-for-sale investment securities, which at December 31, 2025 and December 31, 2024 consisted entirely of fixed maturity securities, on at least a quarterly basis for the purpose of determining whether declines in fair value below recorded cost basis represent an impairment loss. We consider a credit-related impairment loss to have occurred:

•if there is intent to sell the security;

•if it is more likely than not that the security will be required to be sold before full recovery of its amortized cost basis; or

•if the entire amortized basis of the security is not expected to be recovered.

The assessment of whether the amortized cost basis of a security is expected to be recovered requires management to make assumptions regarding various matters affecting future cash flows. The choice of assumptions is subjective and requires the use of judgment. Actual credit losses experienced in future periods may differ from management’s current estimates of those credit losses. Methodologies used to estimate the present value of expected cash flows are:

The estimate of expected cash flows is determined by projecting a recovery value and a recovery time frame and assessing whether further principal and interest will be received. We consider various factors in projecting recovery values and recovery time frames, including the following:

•third-party research and credit rating reports;

•the current credit standing of the issuer, including credit rating downgrades, whether before or after the balance sheet date;

•the extent to which the decline in fair value is attributable to credit risk specifically associated with the security or its issuer;

•internal assessments and the assessments of external portfolio managers regarding specific circumstances surrounding an investment, which indicate the investment is more or less likely to recover its amortized cost than other investments with a similar structure;

•for asset-backed securities, the origination date of the underlying loans, the remaining average life, the probability that credit performance of the underlying loans will deteriorate in the future and our assessment of the quality of the collateral underlying the loan;

•failure of the issuer of the security to make scheduled interest or principal payments;

•any changes to the rating of the security by a rating agency;

•recoveries or additional declines in fair value subsequent to the balance sheet date;

•adverse legal or regulatory events;

•significant deterioration in the market environment that may affect the value of collateral (e.g., decline in real estate prices);

•significant deterioration in economic conditions; and

•disruption in the business model resulting from changes in technology or new entrants to the industry.

If deemed appropriate and necessary, a discounted cash flow analysis is performed to confirm whether a credit loss exists and, if so, the amount of the credit loss. We use the single best estimate approach for available-for-sale debt securities and consider all reasonably available data points, including industry analyses, credit ratings, expected defaults and the remaining payment terms of the debt security. For fixed rate available-for-sale debt securities, cash flows are discounted at the security's effective interest rate implicit in the security at the date of acquisition. If the available-for-sale debt security’s contractual interest rate varies based on subsequent changes in an independent factor, such as an index or rate, for example, the prime rate, the SOFR, or the U.S. Treasury bill weekly average, that security’s effective interest rate is calculated based on the factor as it changes over the life of the security. If we intend to sell a debt security or believe we will more likely than not be required to sell a debt security before the amortized cost basis is recovered, any existing allowance will be written off against the security's amortized cost basis, with any remaining difference between the debt security's amortized cost basis and fair value recognized as an impairment loss in earnings.

Exclusive of securities where there is an intent to sell or where it is not more likely than not that the security will be required to be sold before recovery of its amortized cost basis, impairment for debt securities is separated into a credit component and a non-credit component. The credit component of an impairment is the difference between the security’s amortized cost basis and the present value of its expected future cash flows, while the non-credit component is the remaining difference between the security’s fair value and the present value of expected future cash flows. An allowance for expected credit losses will be recorded for the expected credit losses through income and the non-credit component is recognized in OCI. The amount of impairment recognized is limited to the excess of the amortized cost over the fair value of the available-for-sale debt security.

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Deferred Taxes

Deferred federal income taxes arise from the recognition of temporary differences between the basis of assets and liabilities determined for financial reporting purposes and the basis determined for income tax purposes. Our temporary differences principally relate to our loss reserves, unearned and advanced premiums, DPAC, NOL and tax credit carryforwards, compensation related items, unrealized investment gains (losses) and basis differences on fixed assets, intangible assets and operating leases. Deferred tax assets and liabilities are measured using the enacted tax rates expected to be in effect when such benefits are realized. We review our deferred tax assets quarterly for impairment. If we determine that it is more likely than not that some or all of a deferred tax asset will not be realized, a valuation allowance is recorded to reduce the carrying value of the asset. In assessing the need for a valuation allowance, management is required to make certain judgments and assumptions about our future operations based on historical experience and information as of the measurement period regarding reversal of existing temporary differences, carryback capacity, future taxable income of the appropriate character (including its capital and operating characteristics) and tax planning strategies.

A large portion of our deferred tax asset at December 31, 2025 is related to net unrealized investment losses on our fixed maturities due to the significant effect of fluctuations in interest rates that began in 2022. Future changes in interest rates could cause significant fluctuations in the deferred tax asset. Any loss realized prior to recovery would require sufficient income of the appropriate character (i.e., capital gains), and in the appropriate time frame, to realize the tax benefit. We believe that we have the intent and ability to hold these securities until their recovery. Our projected positive operating income, including the investment income generated from holding our debt securities until maturity, support our ability to implement this tax planning strategy.

A valuation allowance was established in a prior year against the deferred tax asset related to the NOL carryforwards for our U.K. operations and against a portion of the deferred tax asset related to our U.S. state NOL carryforwards. Management concluded that it was more likely than not that these deferred tax assets will not be realized. We also established a valuation allowance in a prior year against the deferred tax assets of certain SPCs at our wholly owned Cayman Islands reinsurance subsidiary, Inova Re. Due to the cumulative losses incurred in recent years by these SPCs, management concluded that a valuation allowance was required. As of December 31, 2025, management concluded that the previously recorded valuation allowances were still required against the deferred tax assets related to the NOL carryforwards for our U.K. operations, against the deferred tax assets related to some of our U.S. state NOL carryforwards and the deferred tax assets of certain SPCs at Inova Re. Management’s assessment of the need for these valuation allowances at December 31, 2025 included an analysis of all available sources of income. See further discussion on ProAssurance’s deferred tax assets in Note 5 of the Notes to Consolidated Financial Statements.

U.S. Tax Legislation

One Big Beautiful Bill Act

The OBBBA was signed into law on July 4, 2025 and included extensions and modifications to various domestic and international tax provisions that were originally enacted under the TCJA. Under current accounting guidance, the effects of changes in tax law are accounted for in the period of enactment or the date the President signs the bill. These changes do not have a material impact on our effective tax rate or on our current or deferred taxes.

Liquidity and Capital Resources and Financial Condition

Overview

ProAssurance Corporation is a holding company and is a legal entity separate and distinct from its subsidiaries. As a holding company, our principal source of external revenue is our investment revenues. In addition, dividends from our operating subsidiaries represent another source of funds for our obligations, including debt service. We also charge our core domestic operating subsidiaries within our Specialty P&C and Workers' Compensation Insurance segments a management fee based on the extent to which services are provided to the subsidiary and the amount of gross premium written by the subsidiary. At December 31, 2025, we held cash and liquid investments of approximately $166 million outside our insurance subsidiaries that were available for use without regulatory approval or other restriction. As of February 18, 2026, we also have an additional $125 million in permitted borrowings available under our Revolving Credit Agreement as well as the possibility of a $50 million accordion feature, if successfully subscribed, as discussed in this section under the heading "Debt."

During 2025, our operating subsidiaries paid dividends to us of $113 million. Our insurance subsidiaries, in the aggregate, are permitted to pay dividends of approximately $164 million over the course of 2026 without prior approval of state insurance regulators. However, the payment of any dividend requires prior notice to the insurance regulator in the state of domicile, and the regulator may reduce or prevent the dividend if, in its judgment, payment of the dividend would have an adverse effect on the surplus of the insurance subsidiary. We make the decision to pay dividends from an insurance subsidiary based on the

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capital needs of that subsidiary and may pay less than the permitted dividend or may also request permission to pay an additional amount (an extraordinary dividend).

Cash Flows

Cash flows between periods compare as follows:

Year Ended December 31
(In thousands)20252024Change
Net cash provided by (used in):
Operating activities$(25,620)$(10,715)$(14,905)
Investing activities19,43610,6728,764
Financing activities(12,203)(10,974)(1,229)
Increase (decrease) in cash and cash equivalents$(18,387)$(11,017)$(7,370)

The principal components of our operating cash flows are the excess of premiums collected and net investment income over losses paid and operating costs, including income taxes. Timing delays exist between the collection of premiums and the payment of losses associated with the premiums. Premiums are generally collected within the twelve-month period after the policy is written, while our claim payments are generally paid over a more extended period of time. Likewise, timing delays exist between the payment of claims and the collection of any associated reinsurance recoveries.

Operating cash flows decreased in 2025 as compared to 2024. The change in operating cash flows was primarily due to:

•A decrease in net premium receipts of $31.8 million primarily driven by a lower volume of written premium due to the proactive actions we have taken in certain lines of business to improve profitability, partially offset by a decrease in premiums paid for reinsurance.

•An increase in cash paid for operating expenses of $25.1 million driven by higher incentive based compensation and transaction-related costs associated with the proposed merger transaction with The Doctors Company (see Note 1 of the Notes to the Consolidated Financial Statements).

The decrease in operating cash flows was partially offset by:

•A decrease in paid net losses of $33.8 million driven by our Specialty P&C segment which reflected a lower number of claims resolved with large indemnity payments as compared to the prior year period.

•An increase in cash received from investment income of $7.2 million driven by higher average book yields as we take advantage of the current interest rate environment as our portfolio matures and an increase in distributed earnings and redemptions from our portfolio of investments in LPs/LLCs.

The remaining variance in operating cash flows in 2025 as compared to 2024 was composed of individually insignificant components.

We manage our investing cash flows to ensure that we will have sufficient liquidity to meet our obligations, taking into consideration the timing of cash flows from our investments, including interest payments, dividends and principal payments, as well as the expected cash flows to be generated by our operations as discussed in this section under the heading "Investing Activities and Related Cash Flows."

Our financing cash flows are primarily comprised of repayment of debt as well as capital contributions received from or return of capital to external SPC participants. See further discussion of debt in this section under the heading "Financing Activities and Related Cash Flows."

Operating Activities and Related Cash Flows

Losses

The following table, known as the Analysis of Reserve Development, presents information over the preceding ten years regarding the payment of our losses as well as changes to (the development of) our estimates of losses during that time period. As noted in the table, we have completed various acquisitions over the ten year period which have affected original and re-estimated gross and net reserve balances as well as loss payments.

The table includes losses on both a direct and an assumed basis and is net of anticipated reinsurance recoverables. The gross liability for losses before reinsurance, as shown on the balance sheet, and the reconciliation of that gross liability to amounts net of reinsurance are reflected below the table. We do not discount our reserve for losses to present value. Information presented in the table is cumulative and, accordingly, each amount includes the effects of all changes in amounts for prior years.

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The table presents the development of our balance sheet reserve for losses; it does not present accident year or policy year development data. Conditions and trends that have affected the development of liabilities in the past may not necessarily occur in the future. Accordingly, it is not appropriate to extrapolate future redundancies or deficiencies based on this table.

The following may be helpful in understanding the Analysis of Reserve Development:

•The line entitled “Reserve for losses, undiscounted and net of reinsurance recoverables” reflects our reserve for losses and loss adjustment expense, less the receivables from reinsurers, each as reported in our Consolidated Balance Sheets at the end of each year (the Balance Sheet Reserves).

•The section entitled “Cumulative net paid, as of” reflects the cumulative amounts paid as of the end of each succeeding year with respect to the previously recorded Balance Sheet Reserves.

•The section entitled “Re-estimated net liability as of” reflects the re-estimated amount of the liability previously recorded as Balance Sheet Reserves that includes the cumulative amounts paid and an estimate of the remaining net liability based upon claims experience as of the end of each succeeding year (the Net Re-estimated Liability).

•The line entitled “Net cumulative redundancy (deficiency)” reflects the difference between the previously recorded Balance Sheet Reserve for each applicable year and the Net Re-estimated Liability relating thereto as of the end of the most recent fiscal year.

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Analysis of Reserve Development
December 31
(In thousands)20152016201720182019202020212022202320242025
Reserve for losses, undiscounted and net of reinsurance recoverables$1,730,308$1,681,423$1,659,971$1,709,129$1,878,140$1,945,099$3,059,328$2,973,196$2,888,655$2,775,805$2,663,810
Cumulative net paid, as of:
One Year Later370,973354,526387,389428,940466,904454,902756,601773,912727,893682,439
Two Years Later616,016621,783668,340734,638790,989813,7681,371,3261,342,6701,260,421
Three Years Later799,689800,331857,177952,3091,046,5731,101,0501,790,9591,735,870
Four Years Later898,844930,769990,0231,133,4621,249,1961,288,8732,084,368
Five Years Later974,1041,004,9511,085,2671,265,9711,373,2631,423,442
Six Years Later1,018,1481,061,4881,162,3711,337,0951,453,834
Seven Years Later1,051,4951,110,3111,198,5221,382,424
Eight Years Later1,078,6471,130,9361,217,283
Nine Years Later1,092,0231,143,482
Ten Years Later1,101,055
Re-estimated net liability as of:
End of Year1,730,3081,681,4231,659,9711,709,1291,878,1401,945,0993,059,3282,973,1962,888,6552,775,805
One Year Later1,587,0291,547,8761,565,8671,696,8931,827,1531,902,8133,015,2412,975,7932,841,6232,677,020
Two Years Later1,460,6601,444,6191,487,9051,656,6151,805,4331,885,4563,025,7862,928,7572,751,105
Three Years Later1,356,0751,337,5711,446,5711,647,2831,792,2021,890,5782,982,0072,831,964
Four Years Later1,257,6501,306,2741,432,4771,632,8361,768,4511,872,5842,902,295
Five Years Later1,231,7131,299,0321,415,0771,605,3741,746,8681,845,609
Six Years Later1,230,5621,287,7311,394,6241,593,1341,740,595
Seven Years Later1,217,7131,277,8841,384,2161,588,479
Eight Years Later1,216,7271,274,5191,381,199
Nine Years Later1,212,3291,273,957
Ten Years Later1,215,835
Net cumulative redundancy (deficiency)$514,473$407,466$278,772$120,650$137,545$99,490$157,033$141,232$137,550$98,785
Original gross liability - end of year$1,990,266$1,961,436$1,971,303$2,037,274$2,243,133$2,295,279$3,469,417$3,373,260$3,303,558$3,155,771
Reinsurance recoverables(259,958)(280,013)(311,332)(328,145)(364,993)(350,180)(410,089)(400,064)(414,903)(379,966)
Original net liability - end of year$1,730,308$1,681,423$1,659,971$1,709,129$1,878,140$1,945,099$3,059,328$2,973,196$2,888,655$2,775,805
Gross re-estimated liability - latest$1,445,425$1,520,111$1,633,653$1,878,560$2,073,248$2,179,288$3,319,842$3,238,788$3,120,738$3,026,107
Re-estimated reinsurance recoverables(229,590)(246,154)(252,454)(290,081)(332,653)(333,679)(417,547)(406,824)(369,633)(349,087)
Net re-estimated liability - latest$1,215,835$1,273,957$1,381,199$1,588,479$1,740,595$1,845,609$2,902,295$2,831,964$2,751,105$2,677,020
Gross cumulative redundancy (deficiency)$544,841$441,325$337,650$158,714$169,885$115,991$149,575$134,472$182,820$129,664

See table notes on following page.

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Table Notes

•We have elected to present reserve history for acquired entities on a prospective basis in the table above; therefore, certain items will not agree to the following table which details activity in our net reserve for losses.

•Given the Lloyd's Syndicates operations are in run-off and the reserve is relatively small on a standalone basis as compared to our consolidated reserve, we have elected to exclude its reserve history for all periods presented in the table above, which is consistent with prior year; therefore, certain items will not agree to the following table which details activity in our net reserve for losses.

•Reserves for 2021 include gross and net reserves acquired in 2021 business combinations of $1.2 billion and $1.1 billion, respectively.

In each year reflected in the table, we have estimated our reserve for losses utilizing the management and actuarial processes discussed under the heading "Reserve for Losses and Loss Adjustment Expenses" in the Critical Accounting Estimates section. Factors that have contributed to the variation in loss development are primarily related to the extended period of time required to resolve professional liability claims and include the following:

•The MPL legal environment deteriorated in the late 1990’s and severity began to increase at a greater pace than anticipated in our rates and reserve estimates. We addressed the adverse severity trends through increased rates, stricter underwriting and modifications to claims handling procedures, and reflected this adverse severity trend when we established our initial reserves for subsequent years.

•These adverse severity trends later moderated, with that moderation becoming more pronounced beginning in 2009. We were cautious in giving full recognition to indications that the pace of severity increase had slowed, however we gave measured recognition of the improved trend in our reserve estimates. The favorable development was most pronounced for years 2004 to 2008, as the initial reserves for these accident years were established prior to substantial indication that severity trends were moderating. We gave stronger recognition to the lower severity trend as time elapsed and a greater percentage of claims were closed.

•A general decline in claims frequency has also been a contributor to favorable loss development. A significant portion of our policies through 2003 were issued on an occurrence basis, and a smaller portion of our ongoing business results from the issuance of extended reporting endorsements which have occurrence-like exposure. As claims frequency declined, the number of reported claims related to these coverages was less than originally expected.

•Beginning in 2017, we identified potential higher severity trends in the broader MPL industry. These trends were also reflected in increases in estimates of ultimate losses for open MPL claims for earlier accident years, which resulted in a lower amount of favorable development recognized in 2018 and 2017 as compared to prior years.

•During 2019 the loss experience in our Specialty book in our Specialty P&C segment deteriorated further, particularly in regard to the reserves we established for a large national healthcare account that experienced losses far exceeding the assumptions we made when underwriting the account, beginning in 2016. As a result, we strengthened our Specialty reserves through the recognition of net unfavorable development on prior accident years and a higher current accident year net loss ratio in our Specialty P&C segment in 2019.

•Beginning in the second half of 2023 and throughout 2024, we observed higher than expected loss trends in our average cost per claim in our Workers' Compensation Insurance segment, which we primarily attributed to increased medical costs driven by wage inflation and medical advancements. We implemented various medical cost management initiatives during 2025 to address the medical cost severity and we have observed improvements in the average medical cost per claim. However, an increase in severity-related claim activity on large losses more than offset medical cost savings related to these initiatives. In response to this trend, we increased our full year current accident year net loss ratio in our Workers' Compensation Insurance segment from 75% at September 30, 2025 to 77% at December 31, 2025.

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Activity in our net reserve for losses during 2025, 2024 and 2023 is summarized below:

Year Ended December 31
(In thousands)202520242023
Balance, beginning of year$3,257,696$3,401,281$3,471,147
Less reinsurance recoverables on unpaid losses and loss adjustment expenses409,069445,573431,889
Net balance, beginning of year2,848,6272,955,7083,039,258
Net losses:
Current year(1)755,732779,650794,848
(Favorable) unfavorable development of reserves established in prior years, net(1)(90,314)(40,215)5,646
Total665,418739,435800,494
Paid related to:
Current year(102,589)(106,443)(105,133)
Prior years(743,592)(733,248)(782,048)
Total paid(846,181)(839,691)(887,181)
Foreign currency exchange rate (gains) losses(2)15,920(6,825)3,137
Net balance, end of year2,683,7842,848,6272,955,708
Plus reinsurance recoverables on unpaid losses and loss adjustment expenses334,612409,069445,573
Balance, end of year$3,018,396$3,257,696$3,401,281

(1) Net prior accident year reserve development recognized for the years ended December 31, 2025, 2024 and 2023 included certain purchase accounting adjustments associated with our acquisition of NORCAL. See Note 6 of the Notes to Consolidated Financial Statements for additional information.

(2) Foreign currency exchange rate (gains) losses are related to foreign currency denominated loss reserves associated with international insurance exposures in our Specialty P&C segment, primarily related to a strategic partnership with an international medical professional liability insured. Foreign currency exchange rate (gains) losses on foreign currency denominated loss reserves are reflected through net income (loss) as a component of other income (expense) in the Consolidated Statements of Income and Comprehensive Income and reported in our Corporate segment.

At December 31, 2025 our gross reserve for losses included case reserves of approximately $1.9 billion and IBNR reserves of approximately $1.1 billion. Our consolidated gross reserve for losses on a GAAP basis exceeds the combined gross reserves of our insurance subsidiaries on a statutory basis by approximately $125 million, which is principally due to the portion of the GAAP reserve for losses that is reflected for statutory accounting purposes as unearned premiums. These unearned premiums are applicable to extended reporting endorsements (“tail” coverage) issued without a premium charge upon death, disability or retirement of an insured who meets certain qualifications.

Reinsurance

Within our Specialty P&C segment, we use insurance and reinsurance (collectively, “reinsurance”) to provide capacity to write larger limits of liability, to provide reimbursement for losses incurred under the higher limit coverages we offer and to provide protection against losses in excess of policy limits. Within our Workers' Compensation Insurance segment, we use reinsurance to reduce our net liability on individual risks, to mitigate the effect of significant loss occurrences (including catastrophic events), to stabilize underwriting results and to increase underwriting capacity by decreasing leverage. In both our Specialty P&C and Workers' Compensation Insurance segments, we use reinsurance in risk sharing arrangements to align our objectives with those of our strategic business partners and to provide custom insurance solutions for large customer groups. The purchase of reinsurance does not relieve us from the ultimate risk on our policies; however, it does provide reimbursement for certain losses we pay. We pay our reinsurers a premium in exchange for reinsurance of the risk. In certain of our excess of loss arrangements, the premium due to the reinsurer is determined by the loss experience of the business reinsured, subject to certain minimum and maximum amounts. Until all loss amounts are known, we estimate the premium due to the reinsurer. Changes to the estimate of premium owed under reinsurance agreements related to prior periods are recorded in the period in which the change in estimate occurs and can have a significant effect on net premiums earned.

We offer alternative market solutions whereby we cede certain premiums from our Workers' Compensation Insurance and Specialty P&C segments to either the SPCs at Inova Re, one of our Cayman Islands reinsurance subsidiaries which is reported

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in our Segregated Portfolio Cell Reinsurance segment, or captive insurers unaffiliated with ProAssurance for two programs. The majority of these policies are reinsured to the SPCs at Inova Re, net of a ceding commission. See further discussion on our SPC operations in the Segment Results - Segregated Portfolio Cell Reinsurance section that follows. The alternative market workers' compensation policies are ceded from our Workers' Compensation Insurance segment to the SPCs under 100% quota share reinsurance agreements. The alternative market medical professional liability policies are ceded from our Specialty P&C segment to the SPCs under either excess of loss or quota share reinsurance agreements, depending on the structure of the individual program. The portion of the risk that is not ceded to an SPC is retained in our Specialty P&C segment and may also be reinsured under our standard medical professional liability reinsurance program, depending on the policy limits provided. The remaining premium written in our alternative market business is 100% ceded to unaffiliated captive insurers.

Excess of Loss Reinsurance Agreements

We generally reinsure risks under treaties (our excess of loss reinsurance agreements) pursuant to which the reinsurers agree to assume all or a portion of all risks that we insure above our individual risk retention levels, up to the maximum individual limits offered. These agreements are negotiated and renewed annually. Our Medical Professional Liability and Medical Technology Liability treaties renew annually on October 1 and our workers' compensation treaty renews annually on May 1. Our MPL and Medical Technology Liability treaties renewed October 1, 2025. For our MPL treaty, there was a decrease in reinstatement premiums provisions and a slight reduction to the gross rate paid under the renewed treaty. Retention of our Medical Technology Liability coverages in excess of $2 million increased to 6% from 0% of the next $8 million of risk. All other terms were consistent with the expiring treaties. Our traditional workers' compensation treaty renewed May 1, 2025 at a lower contract rate than the previous treaty. All other material terms were consistent with the expiring treaty. The significant coverages provided by our current excess of loss reinsurance agreements are depicted in the following table.

Current Excess of Loss Reinsurance Agreements

Column 1Column 2Column 3Column 4Column 5Column 6
MedicalProfessional LiabilityMedical Technology & Life Sciences ProductsWorkers' Compensation - Traditional

(1) Effective October 1, 2025, total reinsured limits decreased to $19M from $24M. Since we were not writing policies with these higher limits of coverage, the reduction in limit is not significant. One prepaid limit reinstatement of $16M and a second limit reinstatement of up to $16M for the second layer, subject to reinstatement premium, which attaches after the first reinstatement has been completely exhausted. Historically, the prepaid limit reinstatement and second limit reinstatement ranged from $16M to $21M. All limit reinstatements thereafter require no additional premium. Effective October 1, 2021, limits can be reinstated a maximum of four times.

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(2) Prior to October 1, 2020, retention was $1M.

(3) Historically, retention has ranged from 0% to 32.5%.

(4) Historically, retention has ranged from $1M to $2M.

(5) Subject to a limit of $20M per individual claimant. If an individual loss were to exceed this level the Company would retain this excess exposure. Historically, the limit per individual claimant has ranged from $15M to $20M.

(6) Historically, retention has ranged from $0.5M to $0.75M.

Large MPL risks that are above the limits of our basic reinsurance treaties may be reinsured on a facultative basis, whereby the reinsurer agrees to insure a particular risk up to a designated limit. We also have in place a number of risk sharing arrangements that apply to the first $1 million of losses for certain large healthcare systems and other insurance entities.

Other Reinsurance Arrangements

For the workers' compensation business ceded to Inova Re; each SPC has in place its own reinsurance arrangements, which are illustrated in the following table.

Segregated Portfolio Cell Reinsurance

Column 1Column 2Column 3
Per Occurrence CoverageAggregate Coverage

(1) The attachment point is based on a percentage of written premium within individual cells, ranges from 85% to 94%, and varies by cell.

Each SPC has participants and the profit or loss of each cell accrues fully to these cell participants. As previously discussed, we participate in certain SPCs to a varying degree. Each SPC maintains a loss fund initially equal to the difference between premium assumed by the cell and the ceding commission. The external participants of each cell provide collateral to us, typically in the form of a letter of credit that is initially equal to the difference between the loss fund of the SPC (amount of funds available to pay losses after deduction of ceding commission) and the aggregate attachment point of the reinsurance. Over time, an SPC's retained profits are considered in the determination of the collateral amount required to be provided by the cell's external participants.

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Taxes

We are subject to the tax laws and regulations of the U.S., Cayman Islands and U.K. We file a consolidated U.S. federal income tax return that includes the parent company and its U.S. subsidiaries, except for ProAssurance American Mutual, A Risk Retention Group. Our filing obligations include a requirement to make quarterly payments of estimated taxes to the IRS using the corporate tax rate effective for the tax year. During the second quarter of 2025, we made an income tax extension payment of $2.8 million for the 2024 tax year.

In response to COVID-19, the CARES Act was signed into law on March 27, 2020 and contains several provisions for corporations, including the initial version of the ERC. In December 2020 and March 2021, the ERC was extended and expanded from 50% of qualified wages to 70%. The 2020 rules limited qualified wages to $10,000 per employee and applied to employers with 100 or fewer full-time employees in 2019. The rules were expanded in 2021 to raise the qualified wage limit to $10,000 per employee, per quarter. As an eligible employer under the provisions of the CARES Act, NORCAL filed a claim for a payroll tax refund during the second quarter of 2023, based on eligible wages paid during 2020, that resulted in a tax refund of $4.4 million, including $0.6 million of related interest accrued, which was received in April 2025.

As a result of the NORCAL acquisition, we have U.S. federal NOL carryforwards, which were approximately $14.5 million as of December 31, 2025. These NOL carryforwards are subject to limitation by Internal Revenue Code Section 382 and will begin to expire in 2035.

Investing Activities and Related Cash Flows

Our investments at December 31, 2025 and December 31, 2024 are comprised as follows:

December 31, 2025December 31, 2024
($ in thousands)Carrying Value% of Total InvestmentCarrying Value% of Total Investment
Fixed maturities, available-for-sale:
U.S. Treasury obligations$219,4025%$243,9035%
U.S. Government-sponsored enterprise obligations9,8521%14,8941%
State and municipal bonds430,06310%446,60110%
Corporate debt1,761,51440%1,727,77540%
Residential mortgage-backed securities591,84112%478,79911%
Commercial mortgage-backed securities213,4815%208,5135%
Other asset-backed securities459,63410%461,72210%
Total fixed maturities, available-for-sale3,685,78783%3,582,20782%
Fixed maturities, trading14,3161%53,1571%
Total fixed maturities3,700,10384%3,635,36483%
Equity investments(1)106,9882%130,1583%
Short-term investments285,6296%254,9225%
BOLI82,7871%80,1792%
Investment in unconsolidated subsidiaries245,4726%259,5386%
Other investments8,4001%7,2661%
Total investments$4,429,379100%$4,367,427100%
(1)Includes $81.1 million and $101.2 million of investment grade bond funds as of December 31, 2025 and 2024, respectively, which are not subject to significant equity price risk.

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At December 31, 2025, 99% of our investments in available-for-sale fixed maturity securities were rated and the average rating was A+. The distribution of our investments in available-for-sale fixed maturity securities by rating were as follows:

December 31, 2025December 31, 2024
($ in thousands)Carrying Value% of Total InvestmentCarrying Value% of Total Investment
Rating*
AAA$528,43915%$571,13916%
AA+773,52221%710,84120%
AA196,9935%208,9866%
AA-164,1554%174,3495%
A+230,9106%248,3537%
A414,32311%413,25911%
A-421,98711%381,74611%
BBB+223,9286%197,1425%
BBB317,9729%297,2668%
BBB-159,1284%138,6934%
Below investment grade253,6047%239,5776%
Not rated8261%8561%
Total$3,685,787100%$3,582,207100%
*Average of three NRSRO sources, presented as an S&P equivalent. Source: S&P, Copyright ©2026, S&P Global Market Intelligence

We manage our investments to ensure that we will have sufficient liquidity to meet our obligations, taking into consideration the timing of cash flows from our investments, including interest payments, dividends and principal payments, as well as the expected cash flows to be generated or used by our operations. In addition to the interest and dividends we will receive from our investments, we anticipate that between $80 million and $170 million of our portfolio will mature (or be paid down) each quarter over the next twelve months and become available, if needed, to meet our cash flow requirements. Our reinvestment rate of cash flows compared to recent years is more intermittent due to anticipated higher severity and paid loss trends in our MPL line of business and our Workers' Compensation Insurance segment. From time to time our cash balances will fluctuate depending on the actual timing of paid losses. The primary outflow of cash at our insurance subsidiaries is related to paid losses and operating costs, including income taxes. The payment of individual claims cannot be predicted with certainty; therefore, we rely upon the history of paid claims in estimating the timing of future claims payments with consideration given to current and anticipated industry trends and macroeconomic conditions. To the extent that we may have an unanticipated shortfall in cash, we may either liquidate securities or borrow funds under existing borrowing arrangements through our Revolving Credit Agreement and the FHLB system. As of February 18, 2026, $175 million could be made available for use through our Revolving Credit Agreement, as discussed in this section under the heading "Debt." Given the duration of our investments, we do not foresee a shortfall that would require us to meet operating cash needs through additional borrowings. Additional information regarding our Revolving Credit Agreement is detailed in Note 9 of the Notes to Consolidated Financial Statements.

At December 31, 2025, our FAL was comprised of cash and cash equivalents and investment securities deposited with Lloyd's which had a fair value of $15.1 million. During 2025, we had a net increase in our FAL of $3.1 million primarily to support accumulated losses from prior years of account, stemming from aviation and catastrophe related losses. Additional information regarding our FAL is detailed in Note 3 of the Notes to Consolidated Financial Statements.

Our investment portfolio continues to be primarily composed of high quality fixed income securities with approximately 92% of our fixed maturities being investment grade securities as determined by national rating agencies. The weighted average effective duration of our fixed maturity securities at December 31, 2025 was 3.37 years; the weighted average effective duration of our fixed maturity securities combined with our short-term securities was 3.13 years.

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The carrying value and unfunded commitments for certain of our investments were as follows:

Carrying ValueDecember 31, 2025
($ in thousands, except expected funding period)December 31, 2025December 31, 2024Unfunded CommitmentExpected funding period in years
Qualified affordable housing project tax credit partnerships(1)$53$247$261
All other investments, primarily investment fund LPs/LLCs245,419259,291203,6084
Total$245,472$259,538$203,634
(1) The carrying value reflects our total commitments (both funded and unfunded) to the partnerships, less any amortization, since our initial investment. We fund these investments based on funding schedules maintained by the partnerships.

Investment fund LPs/LLCs are by nature less liquid and may involve more risk than other investments. We manage our risk through diversification of asset class and geographic location. At December 31, 2025, we had investments in 33 separate investment funds with a total carrying value of $245.4 million which represented approximately 6% of our total investments. Our investment fund LPs/LLCs generate earnings from trading portfolios, secured debt, debt securities, multi-strategy funds and private equity investments, and the performance of these LPs/LLCs is affected by the volatility of equity and credit markets. For our investments in LPs/LLCs, we record our allocable portion of the partnership operating income or loss as the results of the LPs/LLCs become available, typically following the end of a reporting period. As of December 31, 2025, our total funding commitments legally outstanding related to our investments in LPs/LLCs were approximately $203.6 million; however, we anticipate capital of approximately $120 million to be drawn based on our current estimates.

Financing Activities and Related Cash Flows

Treasury Shares

Treasury share activity for 2025, 2024 and 2023 was as follows:

(Share amounts in thousands)202520242023
Treasury shares at the beginning of the period12,60712,6079,464
Shares reacquired, at cost of $50.5 million for 20233,143
Treasury shares at the end of the period12,60712,60712,607

We did not repurchase any common shares subsequent to December 31, 2025, and as of February 18, 2026, our remaining Board authorization was approximately $55.9 million.

Debt

Our outstanding debt consisted of the following:

($ in thousands)December 31, 2025December 31, 2024
Contribution Certificates$182,500$181,163
Revolving Credit Agreement125,000125,000
Term Loan114,063120,313
Total principal421,563426,476
Less unamortized debt issuance costs1,1461,603
Debt less unamortized debt issuance costs$420,417$424,873

Additional information regarding our debt is provided in Note 9 of the Notes to Consolidated Financial Statements.

To manage our exposure to interest rate risk due to variability in the base rate on borrowings under the Revolving Credit Agreement and Term Loan, we entered into two forward-starting interest rate swap agreements ("Interest Rate Swaps"). Additional information regarding our Interest Rate Swaps is provided in Note 10 of the Notes to Consolidated Financial Statements.

Two of our insurance subsidiaries are members of an FHLB. Through membership, those subsidiaries have access to secured cash advances which can be used for liquidity purposes or other operational needs. In order for us to use FHLB proceeds, regulatory approvals may be required depending on the nature of the transaction. To date, those subsidiaries have not materially utilized their membership for borrowing purposes.

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Results of Operations - Year Ended December 31, 2025 Compared to Year Ended December 31, 2024

Selected consolidated financial data for each period is summarized in the table below.

Year Ended December 31
($ in thousands, except per share data)20252024Change
Revenues:
Net premiums written$916,913$953,675$(36,762)
Net premiums earned$934,236$968,250$(34,014)
Net investment result172,774166,7416,033
Net investment gains (losses)(5,486)1,903(7,389)
Other income (expense)(3,496)13,510(17,006)
Total revenues1,098,0281,150,404(52,376)
Expenses:
Net losses and loss adjustment expenses665,418739,435(74,017)
Underwriting, policy acquisition and operating expenses330,417319,33911,078
SPC U.S. federal income tax expense (benefit)2,4131,766647
SPC dividend expense (income)6,8734,4442,429
Interest expense20,83822,342(1,504)
Total expenses1,025,9591,087,326(61,367)
Income (loss) before income taxes72,06963,0788,991
Income tax expense (benefit)21,15410,33410,820
Net income (loss)$50,915$52,744$(1,829)
Non-GAAP operating income (loss)$83,863$50,171$33,692
Earnings (loss) per share:
Basic$0.99$1.03$(0.04)
Diluted$0.99$1.03$(0.04)
Non-GAAP operating income (loss) per share:
Basic$1.63$0.98$0.65
Diluted$1.62$0.98$0.64
Net loss ratio71.2%76.4%(5.2 pts)
Underwriting expense ratio35.4%33.0%2.4 pts
Combined ratio106.6%109.4%(2.8 pts)
Non-GAAP combined ratio(1)104.2%109.0%(4.8 pts)
Operating ratio89.8%94.5%(4.7 pts)
Non-GAAP operating ratio(1)87.4%93.7%(6.3 pts)
Effective tax rate29.4%16.4%13.0 pts
Return on equity(2)4.0%4.6%(0.6 pts)
Non-GAAP operating return on equity(2)6.6%4.4%2.2 pts
(1) Refer to the Executive Summary of Operations section under the heading "Non-GAAP Adjusted Key Ratios" for a reconciliation of our key ratios to Non-GAAP adjusted key ratios.
(2) See further discussion on this calculation in the Executive Summary of Operations section under the heading "Non-GAAP Operating ROE."
In all tables that follow, the abbreviation "nm" indicates that the information or the percentage change is not meaningful.

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Executive Summary of Operations

The following sections provide an overview of our consolidated and segment results of operations for the year ended December 31, 2025 as compared to the year ended December 31, 2024. See the Segment Results sections that follow for additional information regarding each segment's results. For a full discussion of the changes in the financial condition, results of operations and cash flows for the year ended December 31, 2024 as compared to the year ended December 31, 2023, please refer to Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" section of ProAssurance's December 31, 2024 report on Form 10-K.

Revenues

The following table shows our consolidated and segment net premiums earned:

Year Ended December 31
($ in thousands)20252024Change
Net premiums earned
Specialty P&C$724,198$747,942$(23,744)(3.2%)
Workers' Compensation Insurance164,351167,610(3,259)(1.9%)
Segregated Portfolio Cell Reinsurance45,68752,698(7,011)(13.3%)
Consolidated total$934,236$968,250$(34,014)(3.5%)

For the year ended December 31, 2025, consolidated net premiums earned decreased $34.0 million as compared to 2024.

•For our Specialty P&C segment, net premiums earned decreased during 2025 driven by the pro rata effect of a decrease in the volume of premium written during the preceding twelve months, primarily due to proactive actions taken in certain lines to improve profitability, and our ceased participation in Syndicate 1729 for the 2024 underwriting year.

•For our Workers' Compensation Insurance segment, net premiums earned decreased in 2025 driven by changes in our carried EBUB estimate and lower audit premium. The decrease for 2025 was partially offset by the impact of a $1.6 million reduction in reinstatement premium during 2025 as compared to an increase of $0.7 million in 2024.

•Net premiums earned in our Segregated Portfolio Cell Reinsurance segment decreased during 2025 primarily due to the non-renewal of five SPCs during 2025 and the non-renewal of three SPCs during 2024.

The following table shows our consolidated net investment result:

Year Ended December 31
($ in thousands)20252024Change
Net investment income$156,498$144,538$11,9608.3%
Equity in earnings (loss) of unconsolidated subsidiaries16,27622,203(5,927)(26.7%)
Net investment result$172,774$166,741$6,0333.6%

The increase in our consolidated net investment income for the year ended December 31, 2025 as compared to 2024 reflected higher average book yields as we continue to take advantage of the current interest rate environment. Our equity in earnings of unconsolidated subsidiaries decreased in 2025 as compared to 2024 driven by the performance of two LPs/LLCs. These results are typically reported on a one-quarter lag and the decrease reflected lower market valuations during the second and third quarters of 2025.

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The following table shows our total consolidated net investment gains (losses):

Year Ended December 31
($ in thousands)20252024Change
Net impairment losses recognized in earnings$(1,498)$(3,196)$1,698(53.1%)
Contingent Consideration remeasurement gain(1)6,500(6,500)(100.0%)
Other net investment gains (losses)(3,988)(1,401)(2,587)(184.7%)
Net investment gains (losses)$(5,486)$1,903$(7,389)(388.3%)
(1) Represents the change in the fair value of contingent consideration issued in connection with the NORCAL acquisition. We do not consider this adjustment in assessing the financial performance of any of our segments and therefore, we have excluded it from the Segment Results sections that follow. See Note 15 of the Notes to Consolidated Financial Statements for a reconciliation of our segment results to our consolidated results.

For the years ended December 31, 2025 and 2024, we recognized credit-related impairment losses in earnings of $1.5 million and $3.2 million, respectively, primarily related to corporate bonds. Additional information regarding investment impairment losses is provided in Note 3 of the Notes to Consolidated Financial Statements.

We recognized $4.0 million and $1.4 million of other net investment losses for the years ended December 31, 2025 and 2024, respectively, driven by net realized losses from the sale of certain available-for-sale fixed maturities and, for the year ended December 31, 2024, unrealized holding losses resulting from changes in the fair value of our equity investments.

Consolidated other income (expense) for the year ended December 31, 2025 as compared to 2024 was comprised as follows:

Year Ended December 31
($ in thousands)20252024Change
Foreign currency exchange rate gains (losses)$(10,882)$6,731$(17,613)(261.7%)
Other7,3866,7796079.0%
Other income (expense)$(3,496)$13,510$(17,006)(125.9%)

Excluding foreign currency exchange movements, other income increased for the year ended December 31, 2025 as compared to 2024 driven by gain of $2.2 million associated with the sale of our Franklin, TN property to an unrelated third party and proceeds of $1.0 million associated with the sale of the renewal rights related to our legal professional liability book of business to an unrelated third party in our Specialty P&C segment. Partially offsetting the increase in other income for 2025 was the impact of a $1.7 million adjustment to write-off certain previously capitalized real estate improvements associated with our Birmingham, AL property.

Foreign currency exchange rate gains (losses) are reported in our Corporate segment and are primarily related to foreign currency denominated balances associated with international insurance exposures, primarily related to our strategic partnership with an international medical professional liability insured in our Specialty P&C segment. Due to the size of the loss reserves associated with these international exposures, even nominal movements in exchange rates can lead to volatility in our results of operations.

Beginning in 2025, foreign currency exchange rate gains (losses) include the impacts of our utilization of foreign currency forward contracts. Historically, we mitigated foreign currency exchange exposure by matching the currency and duration of associated investments to the corresponding loss reserves. However, when we invest in foreign currency denominated available-for-sale fixed maturities, in accordance with GAAP, the change in market value due to changes in foreign currency exchange rates is reflected as part of OCI. Conversely, the impact of changes in foreign currency exchange rates on loss reserves is reflected through net income (loss) as a component of other income (expense).

During the first quarter of 2025 we changed our hedging strategy around foreign currency exchange exposures. Instead of investing in foreign currency denominated investments, we began utilizing foreign currency forward contracts. As these forward contracts are designated as economic hedges (non-hedging instruments), the change in fair value of these contracts is reflected through net income (loss) as a component of other income (expense) which is intended to hedge against foreign currency exchange rate gains (losses) related to foreign currency denominated balances also recognized within other income (expense) in the same period. Due to our change in hedging strategy, we sold a majority of our foreign currency denominated available-for-sale fixed maturities during the first quarter of 2025. Due to the sale of those investments, accumulated foreign currency exchange rate losses of $6.5 million were reclassified from AOCI to earnings and are included in other income (expense) in 2025. While the volatility in foreign currency exchange rates had an outsized impact on our results of operations in 2025, the overall impact on our financial position was nominal due to our hedging strategies.

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Expenses

The following table shows our consolidated and segment net loss ratios and net prior accident year reserve development.

Year Ended December 31
($ in millions)20252024Change
Current accident year net loss ratio
Consolidated ratio80.9%80.5%0.4pts
Specialty P&C82.7%82.3%0.4pts
Workers' Compensation Insurance77.0%77.0%pts
Segregated Portfolio Cell Reinsurance65.8%66.8%(1.0pts)
Calendar year net loss ratio
Consolidated ratio71.2%76.4%(5.2pts)
Specialty P&C71.7%77.3%(5.6pts)
Workers' Compensation Insurance75.3%76.7%(1.4pts)
Segregated Portfolio Cell Reinsurance48.7%61.6%(12.9pts)
Favorable (unfavorable) reserve development, prior accident years
Consolidated$90.3$40.2$50.1
Specialty P&C$79.8$36.9$42.9
Workers' Compensation Insurance$2.7$0.5$2.2
Segregated Portfolio Cell Reinsurance$7.8$2.8$5.0

Our consolidated current accident year net loss ratio increased 0.4 percentage points for the year ended December 31, 2025 as compared to 2024.

•Our Specialty P&C segment's current accident year net loss ratio increased 0.4 percentage points for the year ended December 31, 2025 as compared to 2024 driven by higher loss severity and frequency trends in select jurisdictions, which have resulted in an increase to certain expected loss ratios during the fourth quarter of 2025, as well as changes in the mix of business. The increase in the segment's current accident year net loss ratio also reflected higher ULAE costs primarily due to higher compensation, equipment and software costs, partially offset by a decrease in our reserves related to DDR coverage endorsements due to a decrease in business eligible for tail coverage.

•The 2025 current accident year net loss ratio for our Workers' Compensation Insurance segment remained unchanged as compared to 2024. However, during the fourth quarter of 2025, we increased our full year current accident year net loss ratio from 75% at September 30, 2025 to 77% at December 31, 2025 reflecting higher severity-related claim activity on large losses, which more than offset medical cost savings related to medical cost management initiatives that were implemented in the first quarter of 2025.

•The improvement in the Segregated Portfolio Cell Reinsurance segment's current accident year net loss ratio for the year ended December 31, 2025 reflected a reduction in average claim severity and reported claim frequency, partially offset by changes in estimated program year aggregate reinsurance recoveries.

Our consolidated calendar year net loss ratio can be lower than or higher than our consolidated current accident year net loss ratio due to the recognition of either favorable or unfavorable prior accident year reserve development, respectively.

Total net prior accident year reserve development for 2025 and 2024 was as follows:

Year Ended December 31
($ in thousands)20252024Change
Net favorable (unfavorable) reserve development$86,964$34,890$52,074149.3%
NORCAL Acquisition - Purchase Accounting Amortization3,3505,325(1,975)(37.1%)
Total net favorable (unfavorable) reserve development$90,314$40,215$50,099124.6%

Excluding purchase accounting amortization, consolidated net favorable reserve development recognized in 2025 is largely attributable to lower than anticipated loss emergence in our MPL and Medical Technology Liability lines of business in our Specialty P&C segment and, to a lesser extent, the workers' compensation business in our Segregated Portfolio Cell Reinsurance segment, partially offset by net unfavorable reserve development associated with our discontinued Lloyd's

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Syndicates operations. See the Segment Results sections that follow for additional information regarding each segment's current accident year net loss ratio and net prior accident year reserve development.

Our consolidated and segment underwriting expense ratios were as follows:

Year Ended December 31
20252024Change
Underwriting Expense Ratio
Consolidated(1)35.4%33.0%2.4pts
Specialty P&C27.7%27.3%0.4pts
Workers' Compensation Insurance38.5%37.0%1.5pts
Segregated Portfolio Cell Reinsurance35.3%34.3%1.0pts
Corporate(2)3.8%3.8%pts
(1) Consolidated operating expenses for 2025 include $16.4 million of transaction-related costs associated with the proposed merger transaction with The Doctors Company. Consolidated operating expenses for 2024 include $0.3 million of actuarial consulting fees paid in connection with the final determination of contingent consideration associated with the acquisition of NORCAL. These transaction-related costs are not included in a segment as we do not consider these costs in assessing the financial performance of any of our operating or reportable segments. See Note 15 of the Notes to Consolidated Financial Statements for a reconciliation of our segment results to our consolidated results.
(2) There are no net premiums earned associated with the Corporate segment. Ratios shown are the contribution of the Corporate segment to the consolidated ratio (Corporate operating expenses divided by consolidated net premiums earned).

The change in our consolidated underwriting expense ratio for the year ended December 31, 2025 as compared to 2024 was primarily attributable to the following:

(In percentage points)Increase (Decrease) 2025 versus 2024
Estimated ratio increase (decrease) attributable to:
Change in Net Premiums Earned and DPAC amortization(1)0.4 pts
Transaction-related costs1.8 pts
Tail premium(2)(0.4 pts)
All other, net0.6 pts
Increase in the underwriting expense ratio2.4 pts
(1) Excludes tail premium and the impact of ceded premium adjustments related to prior accident years. See further discussion on the ceded premium adjustments in the Segment Results - Specialty Property & Casualty section that follows under the heading "Ceded Premiums Ratio."
(2) Represents the impact of tail premium written in the period as these premiums are typically fully earned when written with minimal associated expenses.

Excluding the impact of the items specifically identified in the table above, our consolidated underwriting expense ratio increased by 0.6 percentage points in 2025 as compared to 2024 driven by higher incentive based compensation in our Specialty P&C segment, an increase in share-based compensation in our Corporate segment, an increase in health insurance costs as well as the pressure of lower earned premium, partially offset by lower professional fees.

As shown in the previous table, our consolidated underwriting expense ratio for 2025 reflected the impact of the change in net premiums earned, excluding tail premium and the impact of ceded premium adjustments related to prior accident years, in relation to the corresponding change in DPAC amortization, resulting in a 0.4 percentage point increase in the ratio as compared to 2024 driven by higher DPAC amortization in our Workers' Compensation Insurance segment largely due to an increase in state employer assessments.

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Taxes

Our consolidated effective tax rates for the years ended December 31, 2025 and 2024 were as follows:

($ in thousands)Year Ended December 31
20252024Change
Income (loss) before income taxes$72,069$63,078$8,99114.3%
Income tax expense (benefit)21,15410,33410,820104.7%
Net income (loss)$50,915$52,744$(1,829)(3.5%)
Effective tax rate29.4%16.4%13.0 pts

We recognized an income tax expense of $21.2 million and $10.3 million for the years ended December 31, 2025 and 2024, respectively. See further discussion on our effective tax rate in the Segment Results - Corporate section that follows under the heading "Taxes."

Operating Ratio

Our operating ratio is our combined ratio, less our investment income ratio. This ratio provides the combined effect of underwriting profitability and investment income. Our consolidated operating ratio for the years ended December 31, 2025 and 2024 was as follows:

Year Ended December 31
20252024Change
Combined ratio106.6%109.4%(2.8pts)
Less: investment income ratio16.8%14.9%1.9pts
Operating ratio89.8%94.5%(4.7pts)

The primary drivers of the change in our consolidated operating ratio were as follows:

(In percentage points)Increase (Decrease) 2025 versus 2024
Estimated ratio increase (decrease) attributable to:
Change in prior accident year reserve development(5.6 pts)
Investment income(1.9 pts)
Transaction-related costs1.8 pts
All other, net1.0 pts
Decrease in the operating ratio(4.7 pts)

Excluding the impact of the items specifically identified in the table above, our operating ratio in 2025 increased by approximately 1.0 percentage point as compared to 2024 driven by higher incentive based compensation in our Specialty P&C segment, an increase in share-based compensation in our Corporate segment, an increase in consolidated health insurance costs as well as the impact of an increase in our Specialty P&C segment's current accident year net loss ratio. See previous discussion in this section under the heading "Expenses" and further discussion in our Segment Results sections that follow.

Non-GAAP Financial Measures

Non-GAAP Operating Income (Loss)

Non-GAAP operating income (loss) is a financial measure that is widely used to evaluate performance within the insurance sector. In calculating Non-GAAP operating income (loss), we have excluded the effects of the items listed in the following table that do not reflect normal results. We believe Non-GAAP operating income (loss) presents a useful view of the performance of our ongoing core insurance operations; however, it should be considered in conjunction with net income (loss) computed in accordance with GAAP.

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The following table is a reconciliation of net income (loss) to Non-GAAP operating income (loss):

Year Ended December 31
(In thousands, except per share data)20252024
Net income (loss)$50,915$52,744
Items excluded in the calculation of Non-GAAP operating income (loss):
Net investment (gains) losses(1)5,486(1,903)
Net investment gains (losses) attributable to SPCs in which no profit/loss is retained(2)1,5851,773
Transaction-related costs(3)16,351320
Foreign currency exchange rate (gains) losses(4)10,882(6,731)
Non-operating income(5)(3,162)
Guaranty fund assessments (recoupments)(491)(873)
Non-core operations(6)6,3825,330
Pre-tax effect of exclusions37,033(2,084)
Tax effect, at 21%(7)(4,085)(489)
After-tax effect of exclusions32,948(2,573)
Non-GAAP operating income (loss)$83,863$50,171
Per diluted common share:
Net income (loss)$0.99$1.03
Effect of exclusions0.63(0.05)
Non-GAAP operating income (loss) per diluted common share$1.62$0.98

(1) Net investment gains (losses) recognized in earnings are primarily driven by changes in the value of investments that are marked to fair value each period, the nature and timing of which are unrelated to our normal operating results. In addition, net investment gains (losses) for the year ended December 31, 2024 include the $6.5 million decrease to the contingent consideration liability.

(2) Net investment gains (losses) on investments related to SPCs are recognized in our Segregated Portfolio Cell Reinsurance segment. SPC results, including any net investment gain or loss, that are attributable to external cell participants are reflected in the SPC dividend expense (income). To be consistent with our exclusion of net investment gains (losses) recognized in earnings, we are excluding the portion of net investment gains (losses) that is included in the SPC dividend expense (income) which is attributable to the external cell participants.

(3) Transaction-related costs in 2025 are attributable to professional fees incurred in relation to the proposed merger transaction with The Doctors Company. Additional information regarding the proposed merger transaction with The Doctors Company is provided in Note 1 of the Notes to the Consolidated Financial Statements. Transaction-related costs in 2024 are attributable to actuarial consulting fees paid during the second quarter of 2024 in relation to the final determination of contingent consideration associated with the NORCAL acquisition. We are excluding these costs as they do not reflect normal operating results and are unique and non-recurring in nature.

(4) Foreign currency exchange rate gains (losses) are reported in our Corporate segment and are primarily related to foreign currency denominated balances associated with international insurance exposures, primarily related to our strategic partnership with an international medical professional liability insured in our Specialty P&C segment. Due to the size of the loss reserves associated with these international exposures, even nominal movements in exchange rates can lead to volatility in our results of operations. We exclude foreign currency exchange rate movements as the nature and timing of these changes are not indicative of our normal core operating results. See previous discussion in this section under the heading "Revenues."

(5) Non-operating income reflects proceeds of $1.0 million associated with the sale of the renewal rights related to our legal professional liability book of business to an unrelated third party in the second quarter of 2025 as well as a gain of $2.2 million associated with the sale of our Franklin, TN property to an unrelated third party in the first quarter of 2025. See additional discussion on the legal professional liability transaction in Part I Item 1. Business under the heading "Specialty Property and Casualty Segment". We are excluding these items as they do not reflect normal operating results and are unique and non-recurring in nature.

(6) Non-core operations include the net underwriting results from operations that are currently in run-off but do not qualify for Discontinued Operations accounting treatment under GAAP. These operations include our Lloyd's Syndicates operations from our previous participation in Syndicate 1729 and Syndicate 6131 as well as our legal professional liability book of business. Net investment gains (losses) recognized in earnings associated with these operations are included in the adjustment for consolidated net investment gains (losses) as described in footnote 1.

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(7) Our statutory tax rate (21%) was applied to these items in calculating net income (loss). Changes in the contingent consideration liability are non-taxable and therefore have no associated income tax impact. The taxes associated with the net investment gains (losses) related to SPCs in our Segregated Portfolio Cell Reinsurance segment are paid by the individual SPCs and are not included in our consolidated tax provision or net income (loss); therefore, both the net investment gains (losses) from our Segregated Portfolio Cell Reinsurance segment and the adjustment to exclude the portion of net investment gains (losses) included in the SPC dividend expense (income) in the table above are not tax effected. There are no taxes associated with our Lloyd’s Syndicates operations in our consolidated tax provision due to the availability of net operating losses and the full valuation allowance recorded against the deferred tax assets. Accordingly, all adjustments related to our Lloyd's Syndicates operations in the table above are not tax effected. The portion of transaction-related costs that is tax deductible was tax effected at the statutory tax rate while the remaining non-deductible portion was not tax effected as there was no associated income tax benefit.

Non-GAAP Adjusted Key Ratios

Certain key performance ratios include the impact of certain before-tax effects of items that do not reflect normal operating results, as discussed in the previous table. We believe adjusting our key ratios for these items presents a useful view of the performance of our ongoing core insurance operations; however, it should be considered in conjunction with ratios computed in accordance with GAAP.

Our consolidated key ratios for the years ended December 31, 2025 and 2024 include the impact of net underwriting results related to non-core operations, guaranty fund assessments and transaction-related costs (see previous discussion on these items in the previous table). Non-core operations include an underwriting loss of $8.1 million and $4.7 million for the years ended December 31, 2025 and 2024, respectively, associated with our Lloyd's Syndicates operations. Also included in non-core operations is the underwriting income of $0.3 million associated with our legal professional liability book of business in 2025 as compared to an underwriting loss of $2.0 million in 2024.

The following table is a reconciliation of our consolidated key ratios to Non-GAAP adjusted key ratios for the years ended December 31, 2025 and 2024:

Year Ended December 31
Consolidated20252024
As ReportedNon-GAAP operating adjustmentsNon-GAAP Adjusted RatiosAs ReportedNon-GAAP operating adjustmentsNon-GAAP Adjusted Ratios
Current accident year net loss ratio80.9%0.4pts81.3%80.5%0.6pts81.1%
Effect of prior accident years’ reserve development(9.7%)(1.2pts)(10.9%)(4.1%)(1.2pts)(5.3%)
Net loss ratio71.2%(0.8pts)70.4%76.4%(0.6pts)75.8%
Underwriting expense ratio35.4%(1.6pts)33.8%33.0%0.2pts33.2%
Combined ratio106.6%(2.4pts)104.2%109.4%(0.4pts)109.0%
Less: Investment Income Ratio16.8%pts16.8%14.9%0.4pts15.3%
Operating ratio89.8%(2.4pts)87.4%94.5%(0.8pts)93.7%

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Our Specialty P&C segment key ratios for the years ended December 31, 2025 and 2024 include the impact of net underwriting results related to non-core operations, as previously discussed, and guaranty fund assessments.

The following table is a reconciliation of our Specialty P&C segment key ratios to Non-GAAP adjusted key ratios for the years ended December 31, 2025 and 2024:

Year Ended December 31
Specialty P&C segment20252024
Segment As ReportedNon-GAAP operating adjustmentsNon-GAAP Adjusted RatiosSegment As ReportedNon-GAAP operating adjustmentsNon-GAAP Adjusted Ratios
Current accident year net loss ratio82.7%0.6pts83.3%82.3%0.8pts83.1%
Effect of prior accident years’ reserve development(11.0%)(1.7pts)(12.7%)(5.0%)(1.5pts)(6.5%)
Net loss ratio71.7%(1.1pts)70.6%77.3%(0.7pts)76.6%
Underwriting expense ratio27.7%pts27.7%27.3%pts27.3%
Combined ratio99.4%(1.1pts)98.3%104.6%(0.7pts)103.9%

Non-GAAP Operating ROE

Non-GAAP operating ROE is a financial measure that is calculated as Non-GAAP operating income (loss) divided by the average of beginning and ending total shareholders’ equity. As previously discussed, in calculating Non-GAAP operating income (loss), we have excluded the effects of certain items that do not reflect normal results. Non-GAAP operating ROE measures the overall after-tax profitability of our ongoing core insurance operations and shows how efficiently capital is being used; however, it should be considered in conjunction with ROE computed in accordance with GAAP. The following table is a reconciliation of ROE to Non-GAAP operating ROE for the years ended December 31, 2025 and 2024:

Year Ended December 31
20252024Change
ROE4.0%4.6%(0.6pts)
Effect of items excluded in the calculation of Non-GAAP operating ROE2.6%(0.2%)2.8pts
Non-GAAP operating ROE6.6%4.4%2.2pts

Non-GAAP operating ROE in 2025 increased by 2.2 percentage points as compared to 2024 driven by a higher amount of prior accident year reserve development in our Specialty P&C and Segregated Portfolio Cell Reinsurance segments as well as an increase in our net investment income due to higher average book yields as we take advantage of the current interest rate environment. See previous discussions in this section under the heading "Executive Summary of Operations" and further discussion in our Segment Results sections that follow.

Non-GAAP Adjusted Book Value per Share

Book value per share is calculated as total GAAP shareholders’ equity divided by the total number of common shares outstanding at the balance sheet date. This ratio measures the net worth of the Company to shareholders on a per share basis.

Non-GAAP adjusted book value per share is a Non-GAAP measure widely used within the insurance sector and is calculated as total shareholders’ equity, excluding AOCI, divided by the total number of common shares outstanding at the balance sheet date. This Non-GAAP calculation measures the net worth of the Company to shareholders on a per share basis excluding AOCI to eliminate the temporary and potentially significant effects of fluctuations in interest rates on our fixed income portfolio; however, it should be considered in conjunction with book value per share computed in accordance with GAAP. Higher interest rates have led to significant unrealized holding losses on our available-for-sale fixed maturity investments resulting in volatility in AOCI in recent years. See Note 11 of the Notes to Consolidated Financial Statements for additional information.

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The following table is a reconciliation of our book value per share to Non-GAAP adjusted book value per share at December 31, 2025 and December 31, 2024:

Book Value Per Share
Book Value Per Share at December 31, 2024$23.49
Less: AOCI Per Share(1)(3.37)
Non-GAAP Adjusted Book Value Per Share at December 31, 202426.86
Increase (decrease) to Non-GAAP Adjusted Book Value Per Share during the year ended December 31, 2025 attributable to:
Net income (loss)0.99
Other(2)(0.03)
Non-GAAP Adjusted Book Value Per Share at December 31, 202527.82
Add: AOCI Per Share(1)(1.58)
Book Value Per Share at December 31, 2025$26.24
(1) Primarily the impact of accumulated unrealized investment gains (losses) on our available-for-sale fixed maturity investments. See Note 11 of the Notes to Consolidated Financial Statements for additional information.
(2) Primarily the impact of an increase in common shares outstanding due to share-based compensation.

Book value increased $2.75 per share from December 31, 2024 to December 31, 2025 driven by the change in AOCI of $1.79 per share largely due to unrealized holding gains on our fixed income investment portfolio which flow directly to AOCI due to a decrease in interest rates since the end of 2024.

The increase of $0.96 per share in Non-GAAP adjusted book value per share from December 31, 2024 to December 31, 2025 reflected net income of $0.99 per share recognized during the year ended December 31, 2025, partially offset by the impact of share-based compensation and changes in common shares outstanding.

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Segment Results - Specialty Property & Casualty

Our Specialty P&C segment focuses on Medical Professional Liability insurance and Medical Technology Liability insurance as discussed in Note 15 of the Notes to Consolidated Financial Statements. The Specialty P&C segment also includes the underwriting results from our Lloyd's Syndicates business and our legal professional liability book of business, both of which are currently in run-off. As previously discussed under the heading "ProAssurance Overview," we changed the composition of our operating and reportable segments during the first quarter of 2025. As a result, we now report the financial results of our subsidiary IAO, Inc. d/b/a ProAssurance Agency in the Specialty P&C segment which were previously reported in the Corporate segment. All prior period segment information has been recast to conform to the current period presentation and the change in presentation had no impact on previously reported consolidated financial results. See further information regarding this presentation change in Note 15 of the Notes to Consolidated Financial Statements.

Segment results reflected the pre-tax profit or loss from these operations including the amortization of certain purchase accounting adjustments. Segment results included the following:

Year Ended December 31
($ in thousands)20252024Change
Net premiums written$705,768$737,502$(31,734)(4.3%)
Net premiums earned$724,198$747,942$(23,744)(3.2%)
Other income (expense)6,3216,588(267)(4.1%)
Net losses and loss adjustment expenses(519,375)(578,486)59,111(10.2%)
Underwriting, policy acquisition and operating expenses(200,436)(204,142)3,706(1.8%)
Segment results$10,708$(28,098)$38,806138.1%
Net loss ratio71.7%77.3%(5.6pts)
Underwriting expense ratio27.7%27.3%0.4pts
Non-GAAP Adjusted Ratios*
Net loss ratio70.6%76.6%(6.0pts)
Underwriting expense ratio27.7%27.3%0.4pts
*See previous discussion under the heading "Non-GAAP Adjusted Key Ratios."

Premiums Written

Changes in our premium volume within our Specialty P&C segment are generally driven by three primary factors: (1) the amount of new business written, (2) our retention of existing business and (3) the premium charged for business that is renewed, which is affected by rates charged and by the amount and type of coverage an insured chooses to purchase. In addition, premium volume may periodically be affected by shifts in the timing of renewals between periods.

The medical professional liability market, which accounts for a majority of the revenues in this segment, remains challenging as physicians continue joining hospitals or larger group practices and, therefore, are no longer purchasing individual or group policies in the standard market. In addition, some competitors have chosen to compete primarily on price. Those carriers have accumulated an excess of capital since approximately 2004 driven largely by drops in claims frequency. They now use that capital to generate higher investment returns supporting operating income over underwriting income. Both factors may impact our ability to write new business and retain existing business. Furthermore, the insurance and reinsurance markets have historically been cyclical, characterized by extended periods of intense price competition and other periods of reduced capacity. The medical professional liability market has historically been particularly affected by these cycles. Underwriting cycles are driven, among other reasons, by excess capacity available to compete for the business. Changes in the frequency and severity of losses may also affect the cycles of the insurance and reinsurance markets significantly.

Gross, ceded and net premiums written were as follows:

Year Ended December 31
($ in thousands)20252024Change
Gross premiums written$776,942$807,463$(30,521)(3.8%)
Less: Ceded premiums written71,17469,9611,2131.7%
Net premiums written$705,768$737,502$(31,734)(4.3%)

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Gross Premiums Written

Gross premiums written by component were as follows:

Year Ended December 31
($ in thousands)20252024Change
Medical Professional Liability(1)(2)$720,733$737,209$(16,476)(2.2%)
Medical Technology Liability(3)41,91644,936(3,020)(6.7%)
Lloyd's Syndicates(4)675,969(5,902)(98.9%)
Other(5)14,22619,349(5,123)(26.5%)
Total Gross Premiums Written$776,942$807,463$(30,521)(3.8%)

(1) Medical Professional Liability premium was our greatest source of premium revenues in 2025 and 2024. The decrease in MPL premium for 2025 as compared to 2024 was driven by retention losses, partially offset by an increase in renewal pricing, new business written, an increase in premiums assumed on a quota share basis through a strategic partnership and, to a lesser extent, an increase in tail coverage premium. Retention losses during 2025 generally reflect our pursuit of rate adequacy in a competitive market where other carriers may not have the same profitability objectives, appreciate the rate need, or are attempting to gain market share despite near term underwriting losses which can be supported by investment returns from excess capital. Renewal pricing increases during 2025 reflect our response to the rising loss cost environment. See a description of our MPL line of business and additional discussion on competitive market conditions in Part I Item 1. Business under the heading "Specialty Property and Casualty Segment" and "Competition," respectively.

(2) We offer alternative risk and self-insurance products on a customized basis. Our custom alternative risk solutions include a turnkey captive solution whereby we cede either all or a portion of the alternative market premium, net of reinsurance, to two SPCs of our wholly owned Cayman Islands reinsurance subsidiary, Inova Re, which is reported in our Segregated Portfolio Cell Reinsurance segment. See further discussion on alternative market gross premiums written in our Segment Results - Segregated Portfolio Cell Reinsurance section under the heading "Gross Premiums Written" that follows.

(3) Our Medical Technology Liability business is marketed throughout the U.S.; coverage is offered on a primary or excess basis, within specified limits, to manufacturers and distributors of medical technology and life sciences products including entities conducting human clinical trials. In addition to the previously listed factors that affect our premium volume, our Medical Technology Liability premium is also impacted by the sales volume of insureds. Our Medical Technology Liability premium decreased in 2025 as compared to 2024 driven by retention losses, partially offset by new business written. Retention losses in 2025 are primarily attributable to an increase in competition on terms and pricing, insureds no longer needing coverage or going out of business, non-payment, merger activity within the industry and the broker losing the account.

(4) Our Lloyd's Syndicates business includes the results from our previous participation in Syndicate 1729 at Lloyd's of London, which is currently in run off. Effective September 2023, we elected to discontinue our participation in the results of Syndicate 1729 beginning with the 2024 underwriting year. For the 2023 underwriting year our participation in the results of Syndicate 1729 was approximately 5%. Our Lloyd’s Syndicates premium during 2025 reflected the impact of our ceased participation.

(5) This component of gross premiums written includes all other product lines within our Specialty P&C segment, primarily professional liability coverage to attorneys and their firms in select areas of practice. On April 15, 2025, we sold the renewal rights related to our legal professional liability book of business to an unrelated third party for $1.0 million. In connection with this transaction, we agreed to continue directly writing renewal policies for a limited period of time and entered into a 100% quota share reinsurance agreement with that third party for policies written on our paper after April 15, 2025. See additional information on the terms of the transaction in Part I Item 1. Business under the heading "Specialty Property and Casualty Segment".

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New business written, retention and the change in renewal pricing for our Specialty P&C segment and by major component, excluding Lloyd's Syndicates, are shown in the table below:

Year Ended December 31
20252024
($ in millions)MPLMedical Technology LiabilityOtherSpecialty P&C SegmentMPLMedical Technology LiabilityOtherSpecialty P&C Segment
New business$29.7$2.8$0.1$32.6$26.8$4.1$0.5$31.4
Retention(1)84%87%58%84%84%91%74%84%
Change in renewal pricing(2)9%%3%8%10%1%4%9%
(1) Calculated as annualized renewed premium divided by all annualized premium subject to renewal. Retention is affected by a number of factors. We may lose insureds to competitors or to alternative insurance mechanisms such as risk retention groups, captive arrangements or self-insurance entities (often when physicians join hospitals or large group practices) or due to pricing or other issues. We may choose not to renew an insured as a result of our underwriting evaluation. Insureds may also terminate coverage because they have left the practice of medicine for various reasons, principally for retirement, death or disability, but also for personal reasons. See further explanation of changes in retention above under the heading "Gross Premiums Written".
(2) We are committed to a rate structure that will allow us to fulfill our obligations to our insureds while generating competitive long-term returns for our shareholders. Our pricing continues to be based on expected losses as indicated by our historical loss data and available industry loss data. In recent years, this practice has resulted in rate increases and we anticipate further rate increases due to indications of increasing projected loss severity. Additionally, the pricing of our business includes the effects of filed rates, surcharges and discounts. Renewal pricing reflects changes in our exposure base, deductibles, self-insurance retention limits and other policy terms and conditions. See further explanation of changes in renewal pricing above under the heading "Gross Premiums Written".

Ceded Premiums Ratio

Ceded premiums represent the amounts owed to our reinsurers for their assumption of a portion of our losses. See previous discussion in our Liquidity and Capital Resources and Financial Condition section under the heading "Reinsurance" for information regarding our MPL and Medical Technology Liability excess of loss reinsurance arrangements.

We pay our reinsurers a ceding premium in exchange for their accepting the risk, and in certain of our excess of loss arrangements, the ultimate amount of which is determined by the loss experience of the business ceded, subject to certain minimum and maximum amounts. Given the length of time that it takes to resolve our claims, many years may elapse before all losses recoverable under a reinsurance arrangement are known. As a part of the process of estimating our loss reserve we also make estimates regarding the amounts recoverable under our reinsurance arrangements. As a result, we may have an adjustment to our estimate of expected losses and associated recoveries for prior year ceded losses under certain loss sensitive reinsurance agreements. During 2025, we decreased our estimate of ceded premiums owed related to prior accident years by $2.0 million, whereas we recorded a net increase in our estimate of ceded premiums owed to reinsurers by $1.4 million in 2024 due to an increase in our estimate of expected losses and associated recoveries for certain prior year ceded losses. Changes to estimates of premiums ceded related to prior accident years are fully earned in the period the changes in estimates occur.

As shown in the table below, our ceded premiums ratio was affected in both 2025 and 2024 by revisions to our estimate of premiums owed to reinsurers related to coverages provided in prior accident years. The ceded premiums ratio was as follows:

Year Ended December 31
20252024Change
Ceded premiums ratio9.2%8.7%0.5pts
Less the effect of adjustments in premiums owed under reinsurance agreements, prior accident years (as previously discussed)(0.3%)0.2%(0.5pts)
Ratio, current accident year9.5%8.5%1.0pts

The above table reflects ceded premiums written, excluding the effect of prior year ceded premium adjustments, as previously discussed, as a percentage of gross premiums written. The increase in our current accident year ceded premiums ratio for 2025 as compared to 2024 was driven by the impact of the aforementioned 100% quota share reinsurance agreement entered into during the second quarter of 2025 related to our legal professional liability policies. The increase in our current accident year ceded premiums ratio also reflected an increase in premiums ceded under our excess of loss reinsurance arrangements primarily due to the incorporation of podiatric and chiropractic policies into our MPL treaty effective October 1, 2024.

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Net Premiums Earned

Net premiums earned consist of gross premiums earned less the portion of earned premiums that we cede to our reinsurers for their assumption of a portion of our losses. Because premiums are generally earned pro rata over the entire policy period, fluctuations in premiums earned tend to lag those of premiums written. The majority of our policies carry a term of one year; however, some of our Medical Technology Liability policies have a multi-year term. Tail coverage premiums are generally 100% earned in the period written because the policies insure only incidents that occurred in prior periods and are not cancellable. Retroactive coverage premiums are 100% earned at the inception of the contract, as all of the associated underlying loss events occurred in the past. Additionally, any ceded premium changes due to changes to estimates of premiums owed under reinsurance agreements for prior accident years are fully earned in the period of change.

Net premiums earned were as follows:

Year Ended December 31
($ in thousands)20252024Change
Gross premiums earned$792,753$818,751$(25,998)(3.2%)
Less: Ceded premiums earned68,55570,809(2,254)(3.2%)
Net premiums earned$724,198$747,942$(23,744)(3.2%)

Gross premiums earned decreased in 2025 as compared to 2024 driven by the pro rata effect of a decrease in the volume of written premium during the preceding twelve months, primarily due to proactive actions taken in certain lines to improve profitability, and our ceased participation in Syndicate 1729 for the 2024 underwriting year.

Ceded premiums earned during 2025 and 2024 included prior accident year ceded premium adjustments of $2.0 million and $1.4 million, respectively, (see previous discussion under the heading "Ceded Premiums Ratio"). After removing the effect of the prior accident year ceded premium adjustment from both years, ceded premiums earned increased by $1.1 million in 2025 as compared to 2024, primarily attributable to the aforementioned 100% quota share reinsurance agreement related to our legal professional liability policies and an increase in premium ceded under our excess of loss arrangements.

Losses and Loss Adjustment Expenses

The determination of calendar year losses involves the actuarial evaluation of incurred losses for the current accident year and the actuarial re-evaluation of incurred losses for prior accident years.

Accident year refers to the accounting period in which the insured event becomes a liability of the insurer. For claims-made policies, which represent the majority of the premiums written in our Specialty P&C segment, the insured event generally becomes a liability when the event is first reported to us and the policy that is in effect at that time covers the claim. For occurrence policies, the insured event becomes a liability when the event takes place, even though the claim may be reported to us at a later date. For retroactive coverages, the insured event becomes a liability at the inception of the underlying contract. We believe that measuring losses on an accident year basis is the best measure of the underlying profitability of the premiums earned in that period, since it associates policy premiums earned with the estimate of the losses incurred related to those policy premiums.

The following tables summarize calendar year net loss ratios for our Specialty P&C segment by separating losses between the current accident year and all prior accident years.

Net Loss Ratios(1)
Year Ended December 31
20252024Change
Calendar year net loss ratio71.7%77.3%(5.6pts)
Less impact of prior accident years on the net loss ratio(11.0%)(5.0%)(6.0pts)
Current accident year net loss ratio(2)82.7%82.3%0.4pts

(1)Net losses, as specified, divided by net premiums earned.

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(2)As shown in the table above, our current accident year net loss ratio increased 0.4 percentage points for the year ended December 31, 2025 as compared to 2024 primarily attributable to the following:

(In percentage points)Increase (Decrease) 2025 versus 2024
Estimated ratio increase (decrease) attributable to:
Non-core operations(1)0.2 pts
Ceded Premium Adjustment, Prior Accident Years(2)(0.5 pts)
Change in ULAE0.3 pts
All other, net0.4 pts
Increase in the current accident year net loss ratio0.4 pts
(1) Non-core operations include our Lloyd's Syndicates operations and legal professional liability book of business, which are in run-off. See previous discussion on these non-core operations under the heading "Non-GAAP Financial Measures."
(2) See previous discussion under the heading "Ceded Premiums Ratio" for additional information.

•Excluding the impact of the items specifically identified in the table above, our current accident year net loss ratio for 2025 as compared to 2024 increased 0.4 percentage points driven by higher loss severity and frequency trends in select jurisdictions, which have resulted in an increase to certain expected loss ratios during the fourth quarter of 2025, as well as changes in the mix of business. The increase in our current accident year net loss ratio was partially offset by a decrease in our reserves related to DDR coverage endorsements due to a decrease in business eligible for tail coverage. In both 2025 and 2024, we decreased our reserves related to DDR coverage endorsements; however, the adjustment was greater in 2025 as compared to 2024.

•ULAE are costs that cannot be attributed to processing a specific claim and are allocated to net losses and loss adjustment expenses from underwriting and operating expenses. In 2025, ULAE increased primarily due to higher compensation, equipment and software costs.

We re-evaluate our previously established reserve each quarter based upon the most recently completed actuarial analysis supplemented by any new analysis, information or trends that have emerged since the date of that study. We also take into account currently available industry trend information. Our internal actuaries perform an in-depth review of our reserve for losses on at least a semi-annual basis using the loss and exposure data of our insurance subsidiaries.

We recognized net favorable (unfavorable) prior accident year reserve development as follows:

Year Ended December 31
($ in thousands)20252024Change
Total net favorable (unfavorable) reserve development$79,774$36,932$42,842116.0%

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The following table shows net favorable (unfavorable) development by component for the years ended December 31, 2025 and 2024:

•MPL: Net favorable reserve development recognized for the year ended December 31, 2025 was primarily due to lower than expected loss emergence principally related to accident years 2019 through 2022. We recognized net favorable reserve development for the year ended December 31, 2024 reflecting overall favorable trends in claim closing patterns relative to expectations, principally related to accident years 2019 through 2021.

•Medical Technology Liability: During both 2025 and 2024, we recognized net favorable reserve development due to lower than expected loss emergence. Net favorable development recognized in 2025 principally related to accident years 2021 through 2023 whereas development recognized in 2024 principally related to accident years 2022 and 2023.

•Lloyd's Syndicates Operations (Participation Discontinued): In 2025 and 2024, the net unfavorable prior accident year reserve development was driven by Syndicate 6131’s 2021 underwriting year for exposures related to aviation coverages in connection with Russia's invasion of Ukraine.

•Purchase Accounting Amortization: Net prior year reserve development for both periods presented included amortization of the purchase accounting fair value adjustment on NORCAL's assumed net reserve and amortization of the negative VOBA associated with NORCAL's DDR reserve, which is recorded as a reduction to net losses and loss adjustment expenses.

•Other: Net unfavorable prior accident year reserve development recognized in 2025 primarily represents an increase for an ECO/XPL claim in our legal professional liability book of business.

A detailed discussion of factors influencing our recognition of loss development is included in our Critical Accounting Estimates section under the heading "Reserve for Losses and Loss Adjustment Expenses." Assumptions used in establishing our reserve are regularly reviewed and updated by management as new data becomes available. Any adjustments necessary are reflected in the then current operations. Due to the size of our reserve, even a small percentage adjustment to the assumptions can have a material effect on our results of operations for the period in which the change is made.

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Underwriting, Policy Acquisition and Operating Expenses

Our Specialty P&C segment underwriting, policy acquisition and operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20252024Change
DPAC amortization$97,824$102,125$(4,301)(4.2%)
Management fees3,7023,845(143)(3.7%)
Other underwriting and operating expenses98,91098,1727380.8%
Total$200,436$204,142$(3,706)(1.8%)

DPAC amortization decreased in 2025 as compared to 2024 driven by a decrease in our share of Syndicate 1729's DPAC amortization due to our ceased participation for the 2024 underwriting year as well as a decrease in agent commissions and brokerage expenses, largely due to a lower volume of premium written.

Management fees are charged pursuant to a management agreement by the Corporate segment to the core domestic insurance subsidiaries within our Specialty P&C segment for services provided based on the extent to which services are provided to the subsidiary and the amount of premium written by the subsidiary. While the terms of the management agreement were consistent between 2025 and 2024, fluctuations in the amount of premium written by each subsidiary can result in corresponding variations in the management fee charged to each subsidiary during a particular period.

Other underwriting and operating expenses increased in 2025 as compared to 2024 primarily attributable to higher compensation-related expenses, partially offset by lower professional fees, lower facilities expense and a decrease in our share of Syndicate 1729's operating expenses due to our ceased participation for the 2024 underwriting year. The increase in compensation-related expenses in 2025 as compared to 2024 primarily reflected higher incentive based compensation, an increase in health insurance costs and annual merit adjustments, partially offset by a decrease in employee headcount. The decrease in professional fees in 2025 was driven by a reduction in fees associated with a data analytics services agreement. The decrease in facilities expense in 2025 was due to the sale of our Franklin, TN property during the first quarter of 2025. The remaining variance in other underwriting and operating expenses for 2025 as compared to 2024 was comprised of individually insignificant components.

Underwriting Expense Ratio (the Expense Ratio)

Our expense ratio for the Specialty P&C segment was as follows:

Year Ended December 31
20252024Change
Underwriting expense ratio27.7%27.3%0.4pts

The change in our expense ratio in 2025 as compared to 2024 was primarily attributable to the following:

(In percentage points)Increase (Decrease) 2025 versus 2024
Estimated ratio increase (decrease) attributable to:
Change in net premiums earned and DPAC amortization(1)0.1 pts
Tail premium(2)(0.3 pts)
All other, net0.6 pts
Increase in the underwriting expense ratio0.4 pts
(1) Excludes tail premium and the impact of ceded premium adjustments related to prior accident years. See previous discussion on the ceded premium adjustments under the heading "Ceded Premiums Ratio."
(2) Represents the impact of tail premium written in the period as these premiums are typically earned when written with minimal associated expenses.

Excluding the impact of the items specifically identified in the table above, our expense ratio increased 0.6 percentage points in 2025 as compared to 2024 driven by higher incentive based compensation and the pressure of lower earned premium, partially offset by lower professional fees and facilities expenses.

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Segment Results - Workers' Compensation Insurance

Our Workers' Compensation Insurance segment includes workers' compensation products provided to employers generally with 1,000 or fewer employees, as discussed in Note 15 of the Notes to Consolidated Financial Statements. Segment results included the following:

Year Ended December 31
($ in thousands)20252024Change
Net premiums written$167,258$166,223$1,0350.6%
Net premiums earned$164,351$167,610$(3,259)(1.9%)
Other income2,0561,8871699.0%
Net losses and loss adjustment expenses(123,795)(128,483)4,688(3.6%)
Underwriting, policy acquisition and operating expenses(63,295)(61,999)(1,296)2.1%
Segment results$(20,683)$(20,985)$3021.4%
Net loss ratio75.3%76.7%(1.4 pts)
Underwriting expense ratio38.5%37.0%1.5 pts

Premiums Written

Our workers’ compensation premium volume is driven by five primary factors: (1) the amount of new business written, (2) retention of our existing book of business, (3) premium rates charged on our renewal book of business, (4) changes in payroll exposure and (5) audit premium.

Gross, ceded and net premiums written were as follows:

Year Ended December 31
($ in thousands)20252024Change
Gross premiums written$235,763$243,404$(7,641)(3.1%)
Less: Ceded premiums written68,50577,181(8,676)(11.2%)
Net premiums written$167,258$166,223$1,0350.6%

Gross Premiums Written

Gross premiums written by product were as follows:

Year Ended December 31
($ in thousands)20252024Change
Traditional business:
Direct$175,378$173,273$2,1051.2%
Other7,2065,9501,25621.1%
Change in EBUB estimate(1,600)2,900(4,500)(155.2%)
Total traditional business(1)180,984182,123(1,139)(0.6%)
Alternative market business(2)54,77961,281(6,502)(10.6%)
Total$235,763$243,404$(7,641)(3.1%)

(1) Traditional gross premiums written decreased during 2025 as compared to 2024 driven by changes in the carried EBUB estimate, lower audit premium and retention losses, partially offset by higher new business writings and renewal premium related to policies previously written as alternative market business. Renewal business reflected premium retention of 84% and rate decreases of 1% for 2025. Rate decreases were more than offset by an increase in payroll exposure. The renewal premium previously written in our alternative market business totaled $3.9 million and related to alternative market programs that were non-renewed in 2025. Renewal and new business results continue to reflect the competitive workers' compensation market conditions, including the impact of compounded state loss cost reductions in our core operating territories.

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(2) A majority of alternative market premiums are ceded to SPCs in our Segregated Portfolio Cell Reinsurance segment. See further discussion on alternative market gross premiums written in our Segment Results - Segregated Portfolio Cell Reinsurance section under the heading "Gross Premiums Written" that follows. We retained sixteen of the twenty-one (three in the fourth quarter) workers' compensation alternative market programs that were up for renewal during the year ended December 31, 2025. Five agency-owned programs were non-renewed and placed in run-off in 2025.

New business, audit premium, renewal retention and renewal price changes for our traditional business and the alternative market business are shown in the table below:

Year Ended December 31
20252024
($ in millions)Traditional BusinessAlternative Market Business(3)Segment ResultsTraditional BusinessAlternative Market Business(3)Segment Results
New business$18.9$3.7$22.6$17.5$3.5$21.0
Audit premium (excluding EBUB)$10.5$3.9$14.4$12.1$3.7$15.8
Retention rate(1)84%90%86%87%84%86%
Change in renewal pricing(2)(1%)(3%)(1%)(2%)(1%)(1%)
(1) We calculate our workers' compensation retention as renewed premium divided by premium available to renew. Our retention rate can be impacted by various factors, including price or other competitive issues, insureds being acquired, or a decision not to renew based on our underwriting evaluation.
(2) The pricing of our business includes an assessment of the underlying policy exposure and market conditions. We continue to base our pricing on expected losses, as indicated by our historical loss data.
(3) Represents alternative market business ceded to SPCs in our Segregated Portfolio Cell Reinsurance segment.

Ceded Premiums Written

Ceded premiums written were as follows:

Year Ended December 31
($ in thousands)20252024Change
Premiums ceded to SPCs(1)$48,301$55,255$(6,954)(12.6%)
Premiums ceded to external reinsurers(2)13,72615,900(2,174)(13.7%)
Other(3)6,4786,0264527.5%
Total ceded premiums written$68,505$77,181$(8,676)(11.2%)
(1) Represents alternative market business that is ceded under 100% quota share reinsurance agreements to the SPCs in our Segregated Portfolio Cell Reinsurance segment. See further discussion on alternative market gross premiums written in our Segment Results - Segregated Portfolio Cell Reinsurance section under the heading "Gross Premiums Written" that follows.
(2) Premiums ceded under our traditional reinsurance treaty are based on premiums earned during the treaty period. The decrease for the year ended December 31, 2025 as compared to 2024 reflected a lower average reinsurance rate that took effect with the May 1, 2025 treaty renewal as well as a $1.6 million reduction in reinstatement premium recognized in 2025 as compared to an increase of $0.7 million in 2024. The 2025 reinstatement premium reduction is related to a large 2021 accident year claim reserve decrease.
(3) This component of ceded premiums written primarily represents alternative market business premiums ceded to unaffiliated captive insurers for two programs that are ceded under 100% quota share reinsurance agreements.

Ceded Premiums Ratio

Ceded premiums ratio was as follows:

Year Ended December 31
20252024Change
Ceded premiums ratio, as reported30.0%32.3%(2.3pts)
Less the effect of:
Premiums ceded to SPCs (100%)19.1%20.9%(1.8pts)
Other3.0%2.4%0.6pts
Ceded premiums ratio (related to external reinsurance), less the effects of above7.9%9.0%(1.1pts)

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The above table reflects traditional ceded premiums earned as a percentage of traditional gross premiums earned. As discussed above, premiums ceded under our traditional reinsurance treaty are based on premiums earned during the treaty period. The decrease in the ceded premiums ratio in 2025 as compared to 2024 primarily reflects a lower average reinsurance rate that took effect with the May 1, 2025 treaty renewal as well as the $1.6 million reduction in reinstatement premium in 2025 as compared to an increase of $0.7 million in 2024, as previously discussed.

Net Premiums Earned

Net premiums earned consist of gross premiums earned less the portion of earned premiums that we cede to SPCs in our Segregated Portfolio Cell Reinsurance segment, external reinsurers and the unaffiliated captive insurers. Because premiums are generally earned pro rata over the entire policy period, fluctuations in premiums earned tend to lag those of premiums written. Our workers’ compensation policies are twelve month term policies, and premiums are earned on a pro rata basis over the policy period. Net premiums earned also include premium adjustments related to the audit of our insureds' payrolls, changes in our estimates related to EBUB and premium adjustments related to retrospectively-rated policies. Payroll audits are conducted subsequent to the end of the policy period and any related premium adjustments are recorded as fully earned in the current period. We evaluate our estimates related to EBUB and retrospectively-rated premium adjustments on a quarterly basis with any adjustments being included in written and earned premium in the current period.

Net premiums earned were as follows:

Year Ended December 31
($ in thousands)20252024Change
Gross premiums earned$234,856$247,745$(12,889)(5.2%)
Less: Ceded premiums earned70,50580,135(9,630)(12.0%)
Net premiums earned$164,351$167,610$(3,259)(1.9%)

Net premiums earned decreased during the year ended December 31, 2025 as compared to 2024 primarily driven by changes in the carried EBUB estimate and lower audit premium. Partially offsetting these factors for 2025 is the impact of the $1.6 million reduction in reinstatement premium as compared to an increase of $0.7 million in 2024, as previously discussed.

Losses and Loss Adjustment Expenses

We estimate our current accident year loss and loss adjustment expenses by developing actual reported losses using historical loss development factors, adjusted to reflect current and expected trends based on various internal analyses and supplemental information. The following table summarizes calendar year net loss ratios by separating losses between the current accident year and all prior accident years. Calendar year and current accident year net loss ratios by component were as follows:

Year Ended December 31
20252024Change
Calendar year net loss ratio75.3%76.7%(1.4pts)
Less impact of prior accident years on the net loss ratio(1.7%)(0.3%)(1.4pts)
Current accident year net loss ratio77.0%77.0%pts

The 2025 current accident year net loss ratio remained unchanged compared to 2024. During the fourth quarter of 2025, we increased our full year current accident year net loss ratio to 77.0%, reflecting higher severity-related claim activity on large losses, which more than offset medical cost savings related to medical cost management initiatives. The current accident year loss ratio in 2025 was also impacted by the reduction in net premiums earned related to a reduction in the carried EBUB estimate, as previously discussed.

We recognized net favorable prior accident year reserve development of $2.7 million for the year ended December 31, 2025 as compared to $0.5 million of net favorable prior accident year reserve development for 2024. The net favorable reserve development recognized in 2025 reflected a reduction of the AAD liability, overall favorable trends in claim closing patterns in the 2024 accident year as well as a large claim reserve reduction from the 2021 accident year, which had previously exceeded the per person maximum limit under our reinsurance contract. In 2024, net favorable reserve development was driven by favorable prior accident year reserve development of $1.6 million, including the reduction of the AAD liability, partially offset by an adjustment to aggregate losses assumed from the Segregated Portfolio Cell Reinsurance segment of $1.1 million. The net favorable development recognized in 2024 reflected overall favorable trends in claim closing patterns in accident years 2017 through 2019 and 2023.

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Underwriting, Policy Acquisition and Operating Expenses

Underwriting, policy acquisition and operating expenses include the amortization of commissions, premium taxes and underwriting salaries, which are capitalized and deferred over the related workers’ compensation policy period, net of ceding commissions earned. The capitalization of underwriting salaries can vary as they are subject to the success rate of our contract acquisition efforts. These expenses also include a management fee charged by our Corporate segment, which represents intercompany charges pursuant to a management agreement. The management fee is based on the extent to which services are provided to the subsidiary and the amount of premium written by the subsidiary.

Our Workers' Compensation Insurance segment underwriting, policy acquisition and operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20252024Change
DPAC amortization(1)$31,548$29,072$2,4768.5%
Management fees1,7731,820(47)(2.6%)
Other underwriting and operating expenses(2)41,33642,055(719)(1.7%)
SPC ceding commission offset(3)(11,362)(10,948)(414)3.8%
Total$63,295$61,999$1,2962.1%

(1) DPAC amortization increased for the year ended December 31, 2025 as compared to 2024, reflecting an increase in state employer assessment liabilities totaling $1.6 million. The increase in the liability reflected our expectation of assessments in excess of the amounts charged and collected from policyholders as determined and promulgated by states in which we operate. The increase in DPAC amortization also reflected the impact of refunds from guaranty fund assessments totaling $0.4 million and $0.9 million in 2025 and 2024, respectively.

(2) Other underwriting and operating expenses decreased for the year ended December 31, 2025 as compared to 2024 driven by lower incentive based compensation. The remaining variance in other underwriting and operating expenses in 2025 as compared to 2024 was comprised of individually insignificant components.

(3) As previously discussed, alternative market premiums written by our Workers' Compensation Insurance segment are 100% ceded, less a ceding commission, to either the SPCs in our Segregated Portfolio Cell Reinsurance segment or unaffiliated captive insurers. The ceding commission charged to the SPCs consists of an amount for fronting fees, cell rental fees, commissions, premium taxes, claims administration fees and risk management fees. The fronting fees, commissions, premium taxes and risk management fees are recorded as an offset to underwriting, policy acquisition and operating expenses. Cell rental fees are recorded as a component of other income and claims administration fees are recorded as ceded ULAE. SPC ceding commissions earned increased for the year ended December 31, 2025 as compared to 2024, primarily reflecting the prior year impact of an adjustment to ceding commissions charged to the SPCs in prior periods related to certain fees, partially offset by the reduction in alternative market written premium.

Underwriting Expense Ratio (the Expense Ratio)

The underwriting expense ratio included the impact of the following:

Year Ended December 31
20252024Change
Underwriting expense ratio, as reported38.5%37.0%1.5pts
Less estimated ratio increase (decrease) attributable to:
Impact of ceding commissions received from SPCs4.7%5.5%(0.8pts)
Impact of audit premium(1.4%)(2.1%)0.7pts
Impact of change in EBUB estimate0.2%(0.5%)0.7pts
Underwriting expense ratio, less listed effects35.0%34.1%0.9pts

Excluding the items noted in the table above, the expense ratio increased for the year ended December 31, 2025 primarily reflecting the impact of the state employer assessment adjustment, as previously discussed.

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Segment Results - Segregated Portfolio Cell Reinsurance

The Segregated Portfolio Cell Reinsurance segment includes the results (underwriting profit or loss, plus investment results, net of U.S. federal income taxes) of SPCs at Inova Re and Eastern Re, our Cayman Islands SPC operations, as discussed in Note 16 of the Notes to Consolidated Financial Statements. SPCs are segregated pools of assets and liabilities that provide an insurance facility for a defined set of risks. Assets of each SPC are solely for the benefit of that individual cell and each SPC is solely responsible for the liabilities of that individual cell. Assets of one SPC are statutorily protected from the creditors of the others. As of December 31, 2025, there were twenty-seven (twelve inactive) SPCs.

Segment results reflect our share of the underwriting and investment results of the SPCs in which we participate, and included the following:

Year Ended December 31
($ in thousands)20252024Change
Net premiums written$43,887$49,950$(6,063)(12.1%)
Net premiums earned$45,687$52,698$(7,011)(13.3%)
Net investment income3,8643,6082567.1%
Net investment gains (losses)2,2592,369(110)(4.6%)
Other income (expenses)2519631.6%
Net losses and loss adjustment expenses(22,248)(32,466)10,218(31.5%)
Underwriting, policy acquisition and operating expenses(16,128)(18,063)1,935(10.7%)
SPC U.S. federal income tax (expense) benefit(1)(2,413)(1,766)(647)36.6%
SPC net results11,0466,3994,64772.6%
SPC dividend (expense) income(2)(6,873)(4,444)(2,429)54.7%
Segment results(3)$4,173$1,955$2,218113.5%
Net loss ratio48.7%61.6%(12.9 pts)
Underwriting expense ratio35.3%34.3%1.0 pts
(1) Represents the provision for U.S. federal income taxes for SPCs at Inova Re, which have elected to be taxed as a U.S. corporation under Section 953(d) of the Internal Revenue Code. U.S. federal income taxes are included in the total SPC net results and are paid by the individual SPCs.
(2) Represents the net (profit) loss attributable to external cell participants.
(3) Represents our share of the net profit (loss) and OCI of the SPCs in which we participate.

Premiums Written

Premiums in our Segregated Portfolio Cell Reinsurance segment are assumed from either our Workers' Compensation Insurance or Specialty P&C segments. Premium volume is driven by five primary factors: (1) the amount of new business written, (2) retention of the existing book of business, (3) premium rates charged on the renewal book of business and, for workers' compensation business, (4) changes in payroll exposure and (5) audit premium.

Gross, ceded and net premiums written were as follows:

Year Ended December 31
($ in thousands)20252024Change
Gross premiums written$51,052$57,904$(6,852)(11.8%)
Less: Ceded premiums written7,1657,954(789)(9.9%)
Net premiums written$43,887$49,950$(6,063)(12.1%)

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Gross Premiums Written

Gross premiums written reflected reinsurance premiums assumed by component as follows:

Year Ended December 31
($ in thousands)20252024Change
Workers' compensation$48,301$55,255$(6,954)(12.6%)
Medical professional liability2,7512,6491023.9%
Gross Premiums Written$51,052$57,904$(6,852)(11.8%)

Gross premiums written for the years ended December 31, 2025 and 2024 were primarily comprised of workers' compensation coverages assumed from our Workers' Compensation Insurance segment. We retained fourteen of the nineteen workers' compensation programs and both of the medical professional liability programs up for renewal for the year ended December 31, 2025. Workers' compensation gross premiums written decreased during the year ended December 31, 2025 as compared to 2024 primarily due to the non-renewal of five agency-owned programs in 2025, which accounted for $4.6 million of the decrease. A majority of policies expiring in these programs during 2025 were renewed as traditional business in our Workers' Compensation Insurance segment or in other alternative market programs. Policies that renewed as traditional business in our Workers' Compensation Insurance segment that were previously written as alternative market policies totaled $3.9 million for 2025. As of December 31, 2025, in-force premium related to policies in the non-renewed programs totaled $5.6 million and we expect to renew the majority of these policies as traditional business or in other alternative market programs in 2026.

Ceded Premiums Ratio

The ceded premiums ratio was as follows:

Year Ended December 31
20252024Change
Ceded premiums ratio14.8%14.4%0.4pts

For the workers' compensation business, each SPC has in place its own external reinsurance coverage. The medical professional liability business is assumed net of reinsurance from our Specialty P&C segment; therefore, there are no ceded premiums related to the medical professional liability business reflected in the table above. Workers' compensation premiums ceded under our SPC reinsurance treaty are based on premiums written during the program year that renews during the treaty period. The above table reflects ceded premiums as a percentage of gross premiums written. The ceded premiums ratio reflects the weighted average reinsurance rates of all SPC programs.

Net Premiums Earned

Net premiums earned consist of gross premiums earned less the portion of earned premiums that the SPCs cede to external reinsurers. Because premiums are generally earned pro rata over the entire policy period, fluctuations in premiums earned tend to lag those of premiums written. Policies ceded to the SPCs are twelve month term policies and premiums are earned on a pro rata basis over the policy period. Net premiums earned also include premium adjustments related to the audit of workers' compensation insureds' payrolls. Payroll audits are conducted subsequent to the end of the policy period and any related adjustments are recorded as fully earned in the current period.

Gross, ceded and net premiums earned were as follows:

Year Ended December 31
($ in thousands)20252024Change
Gross premiums earned$53,116$60,959$(7,843)(12.9%)
Less: Ceded premiums earned7,4298,261(832)(10.1%)
Net premiums earned$45,687$52,698$(7,011)(13.3%)

The decrease in net premiums earned during the year ended December 31, 2025 as compared to 2024 reflected the non-renewal of three SPCs during 2024 and the non-renewal of five SPCs during 2025, as previously discussed.

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Losses and Loss Adjustment Expenses

The following table summarizes the calendar year net loss ratios by separating losses between the current accident year and all prior accident years. The current accident year net loss ratio reflects the aggregate loss ratio for all programs. Loss reserves and associated reinsurance are estimated for each program on a quarterly basis. Each SPC has in place its own reinsurance agreement, and the attachment point of aggregate reinsurance coverage varies by program. Due to the size of some of the programs, quarterly loss results, including changes in estimated aggregate reinsurance, can create volatility in the current accident year net loss ratio from period to period.

Calendar year and current accident year net loss ratios for the years ended December 31, 2025 and 2024 were as follows:

Year Ended December 31
20252024Change
Calendar year net loss ratio48.7%61.6%(12.9pts)
Less impact of prior accident years on the net loss ratio(17.1%)(5.2%)(11.9pts)
Current accident year net loss ratio65.8%66.8%(1.0pts)

The current accident year net loss ratio decreased in 2025 as compared to 2024, primarily reflecting a reduction in average claim severity and reported claim frequency, partially offset by changes in estimated program year aggregate reinsurance recoveries, which decreased the loss ratio by 0.2 percentage points in 2025 as compared to 1.4 percentage points in 2024.

We recognized net favorable prior year reserve development of $7.8 million and $2.8 million for the years ended December 31, 2025 and 2024, respectively. The development in 2025 includes net favorable development in the workers' compensation business of $7.1 million and the medical professional liability business of $0.7 million. The net favorable development in the workers' compensation business in 2025 reflected favorable trends in claim closing patterns, primarily in accident years 2021 through 2024. The net favorable development in the medical professional liability business in 2025 primarily related to the 2023 and 2024 accident years. The development in 2024 includes net favorable development in the workers' compensation business of $3.1 million, partially offset by net unfavorable development of $0.3 million in the MPL business. The net favorable development in the workers' compensation business in 2024 reflected overall favorable trends in claim closing patterns, primarily in accident years 2018 through 2023. The net unfavorable development in the medical professional liability business in 2024 primarily reflected higher than expected claim frequency in the program that assumed both workers' compensation and medical professional liability insurance, which was non-renewed effective January 1, 2024. We do not participate in the underwriting results of this program.

Underwriting, Policy Acquisition and Operating Expenses

Underwriting Expense Ratio (the Expense Ratio)

See further information regarding our Segregated Portfolio Cell Reinsurance segment's underwriting, policy acquisition and operating expenses in Note 15 of the Notes to Consolidated Financial expenses. The underwriting expense ratio included the impact of the following:

Year Ended December 31
20252024Change
Underwriting expense ratio, as reported35.3%34.3%1.0pts
Less: impact of audit premium on expense ratio(3.3%)(2.6%)(0.7pts)
Underwriting expense ratio, excluding the effect of audit premium38.6%36.9%1.7pts

Excluding the effect of audit premium, the underwriting expense ratio increased for the year ended December 31, 2025 as compared to 2024 primarily reflecting a decrease in net premiums earned, as previously discussed.

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Segment Results - Corporate

Our Corporate segment includes our investment operations excluding those reported in our Segregated Portfolio Cell Reinsurance segment as discussed in Note 15 of the Notes to Consolidated Financial Statements. In addition, this segment includes corporate expenses, interest expense, U.S. and U.K. income taxes and foreign currency exchange rate gains and losses. As previously discussed under the heading "ProAssurance Overview," we changed the composition of our operating and reportable segments during the first quarter of 2025. As a result, we now report the financial results of our subsidiary IAO, Inc. d/b/a ProAssurance Agency in the Specialty P&C segment which were previously reported in the Corporate segment. All prior period segment information has been recast to conform to the current period presentation. The change in presentation had no impact on previously reported consolidated financial results. See further information regarding this presentation change in Note 15 of the Notes to Consolidated Financial Statements.

Segment results for the years ended December 31, 2025 and 2024 exclude transaction-related costs including the associated income tax benefit and, for the year ended December 31, 2024, the change in fair value of contingent consideration as we do not consider these items in assessing the financial performance of the segment. Transaction-related costs in 2025 are attributable to the proposed merger transaction with The Doctors Company. Transaction-related costs in 2024 are associated with actuarial consulting fees paid in relation to the final determination of contingent consideration associated with the NORCAL acquisition. For additional information on the proposed merger transaction with The Doctors Company, see Note 1 of the Notes to Consolidated Financial Statements. Segment results for our Corporate segment were net earnings of $72.0 million and $93.4 million for the years ended December 31, 2025 and 2024, respectively, and included the following:

Year Ended December 31
($ in thousands)20252024Change
Net investment income$152,634$140,930$11,7048.3%
Equity in earnings (loss) of unconsolidated subsidiaries$16,276$22,203$(5,927)(26.7%)
Net investment gains (losses)$(7,745)$(7,206)$(539)(7.5%)
Other income (expense)$(10,813)$6,820$(17,633)(258.5%)
Operating expense$35,292$36,619$(1,327)(3.6%)
Interest expense$20,838$22,342$(1,504)(6.7%)
Income tax expense (benefit)$22,229$10,401$11,828113.7%

Net Investment Income

Net investment income is primarily derived from the income earned by our fixed maturity securities and also includes dividend income from equity securities, income from our short-term and cash equivalent investments, earnings from other investments and changes in the cash surrender value of BOLI contracts, net of investment fees and expenses.

Net investment income (loss) by investment category was as follows:

Year Ended December 31
($ in thousands)20252024Change
Fixed maturities$143,763$131,333$12,4309.5%
Equities4,4464,758(312)(6.6%)
Short-term investments, including Other9,92310,723(800)(7.5%)
BOLI2,6072,31629112.6%
Investment fees and expenses(8,105)(8,200)95(1.2%)
Net investment income$152,634$140,930$11,7048.3%

Fixed Maturities

Income from our fixed maturities increased in 2025 as compared to 2024 driven by higher average book yields as we take advantage of the current interest rate environment as our portfolio matures. Average investment balances were relatively unchanged for 2025 as compared to 2024.

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Average yields for our fixed maturity portfolio were as follows:

Year Ended December 31
20252024
Average income yield3.8%3.5%
Average tax equivalent income yield3.8%3.5%

Short-term Investments and Other Investments

Short-term investments, which have a maturity at purchase of one year or less are carried at fair value, which approximates their cost basis, and are primarily composed of investments in U.S. treasury obligations, commercial paper, money market funds and a certificate of deposit. Income from our short-term and other investments decreased during 2025 as compared to 2024 primarily due to lower average investment balances and lower yields given the decrease in interest rates.

Equity in Earnings (Loss) of Unconsolidated Subsidiaries

Equity in earnings (loss) of unconsolidated subsidiaries was comprised as follows:

Year Ended December 31
($ in thousands)20252024Change
All other investments, primarily investment fund LPs/LLCs$15,443$21,532$(6,089)(28.3%)
Tax credit partnerships83367116224.1%
Equity in earnings (loss) of unconsolidated subsidiaries$16,276$22,203$(5,927)(26.7%)

We hold interests in certain LPs/LLCs that generate earnings from trading portfolios, secured debt, debt securities, multi-strategy funds and private equity investments. The performance of the LPs/LLCs is affected by the volatility of equity and credit markets. For our investments in LPs/LLCs, we record our allocable portion of the partnership operating income or loss as the results of the LPs/LLCs become available, typically following the end of a reporting period. Our investment results from our portfolio of investments in LPs/LLCs decreased for 2025 as compared to 2024 primarily due to the performance of two LPs/LLCs which reflected lower market valuations during the second and third quarters of 2025.

Our tax credit partnership investments are designed to generate returns in the form of tax credits and tax-deductible project operating losses and are comprised of qualified affordable housing project tax credit partnerships and a historic tax credit partnership. We account for our tax credit partnership investments under the equity method and record our allocable portion of the operating losses of the underlying properties based on estimates provided by the partnerships. These tax credit partnership investments are reaching the end of their lifecycle, therefore partnership operating losses and tax benefits associated with these investments have been and are expected to continue to be nominal in amount. However, we may receive distributions from time to time due to the sale of properties, as was the case in 2025 and 2024. See additional information on our tax credit partnership investments in Note 3 of the Notes to Consolidated Financial Statements.

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Net Investment Gains (Losses)

The following table provides detailed information regarding our net investment gains (losses).

Year Ended December 31
(In thousands)20252024
Total impairment losses
Corporate debt$(1,514)$(2,710)
Asset-backed securities248(588)
Other investments(590)
Portion of impairment losses recognized in other comprehensive income before taxes:
Corporate debt355102
Asset-backed securities3
Net impairment losses recognized in earnings(1,498)(3,196)
Gross realized gains, available-for-sale fixed maturities1,9851,522
Gross realized (losses), available-for-sale fixed maturities(5,376)(4,035)
Net realized gains (losses), trading fixed securities5134
Net realized gains (losses), equity investments(2,034)(704)
Net realized gains (losses), other investments(55)(826)
Change in unrealized holding gains (losses), trading fixed securities(59)445
Change in unrealized holding gains (losses), equity investments(366)(1,495)
Change in unrealized holding gains (losses), convertible securities, carried at fair value as a part of other investments(394)866
Other1183
Other net investment gains (losses)(6,247)(4,010)
Net investment gains (losses)$(7,745)$(7,206)

For the year ended December 31, 2025, we recognized $1.5 million of credit-related impairment losses in earnings and $0.4 million of non-credit impairment losses. The credit-related impairment losses in earnings in 2025 primarily related to corporate bonds in the consumer, communication and real estate sectors and a security in the technology sector. For the year ended December 31, 2024, we recognized credit-related impairment losses in earnings of $3.2 million primarily related to corporate bonds in the real estate sector and a nominal amount of non-credit impairment losses in OCI related to a bond in the consumer sector.

We recognized $6.2 million of other net investment losses for the year ended December 31, 2025 driven by net realized losses from the sale of certain available-for-sale fixed maturities and equity investments. We recognized $4.0 million of other net investment losses for the year ended December 31, 2024 driven by net realized losses from the sale of certain available-for-sale fixed maturities and, to a lesser extent, unrealized holding losses resulting from changes in the fair value of our equity investments.

Operating Expenses

Corporate segment operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20252024Change
Operating expenses$40,767$42,284$(1,517)(3.6%)
Management fee offset(5,475)(5,665)190(3.4%)
Total$35,292$36,619$(1,327)(3.6%)

Operating expenses decreased during the year ended December 31, 2025 as compared to 2024 driven by a decrease in professional fees and various other operating expenses, none of which were individually significant, partially offset by an increase in compensation-related costs. The decrease in professional fees during 2025 primarily reflected a decrease in external audit fees and temporary personnel fees. The increase in compensation-related costs during 2025 primarily reflected an increase in share-based compensation expenses attributable to the effect of an increase in the value of projected long-term incentive awards during 2025 based upon the improvement of one of the associated performance metrics and the timing of grants of prior year share-based awards, partially offset by lower incentive based compensation.

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Core domestic insurance subsidiaries within our Specialty P&C segment and our Workers' Compensation Insurance segment are charged a management fee by the Corporate segment for services provided to these subsidiaries. The management fee is based on the extent to which services are provided to the subsidiary and the amount of premium written by the subsidiary. Under the arrangement, the expenses associated with such services are reported as expenses of the Corporate segment, and the management fees charged are reported as an offset to Corporate operating expenses. While the terms of the arrangement were consistent between 2025 and 2024, fluctuations in the amount of premium written by each subsidiary can result in corresponding variations in the management fee charged to each subsidiary during a particular period.

Interest Expense

Interest expense for the years ended December 31, 2025 and 2024 was comprised as follows:

Year Ended December 31
($ in thousands)20252024Change
Contribution Certificates (including accretion)(1)$7,053$7,517$(464)(6.2%)
Revolving Credit Agreement (including fees and amortization)8,58610,244(1,658)(16.2%)
Term Loan (including fees and amortization)7,7449,508(1,764)(18.6%)
(Gain)/loss on cash flow hedges reclassified from AOCI(2,545)(4,927)2,382(48.3%)
Interest expense$20,838$22,342$(1,504)(6.7%)
(1) Includes accretion of approximately $1.3 million and $1.8 million for the years ended December 31, 2025 and 2024, respectively, which is recorded as an increase to interest expense as a result of the difference between the recorded acquisition date fair value and the principal balance of the Contribution Certificates associated with our acquisition of NORCAL.

Interest expense decreased during 2025 as compared to 2024 driven by lower interest expense on our Revolving Credit Agreement and Term Loan due to a decrease in the margin component of the rates based on an improvement in our debt to capitalization ratio as of June 30, 2024. The resulting decrease in interest expense became effective during the third quarter of 2024 and continued into 2025. Interest expense in both periods also includes the impact of our Interest Rate Swaps, which are designated as highly effective cash flow hedges to manage our exposure to interest rate risk due to variability in the base rates on the borrowings under both the Revolving Credit Agreement and Term Loan. See further discussion on our outstanding debt in Note 9 of the Notes to Consolidated Financial Statements and additional information regarding our Interest Rate Swaps is provided in Note 10 of the Notes to Consolidated Financial Statements.

Taxes

Tax expense allocated to our Corporate segment includes U.S. and U.K. tax expense including U.S. tax expense incurred from our corporate membership in Lloyd's of London, if any. The SPCs at Inova Re, one of our Cayman Islands reinsurance subsidiaries, have each made a 953(d) election under the U.S. Internal Revenue Code and are subject to U.S. federal income tax; therefore, tax expense allocated to our Corporate segment also includes tax expense incurred from any SPC at Inova Re in which we have a participation interest of 80% or greater as those SPCs are required to be included in our consolidated tax return. Consolidated tax expense (benefit) reflects the tax expense (benefit) of both segments and the tax impact of items excluded from segment reporting, as shown in the table below. Our consolidated effective tax rates for the years ended December 31, 2025 and 2024 were as follows:

Year Ended December 31
(In thousands)20252024
Corporate segment income tax expense (benefit)$22,229$10,401
Income tax expense (benefit) - transaction-related costs*(1,075)(67)
Consolidated income tax expense (benefit)$21,154$10,334
Effective tax rate29.4%16.4%
*For 2025, represents the income tax benefit associated with the deductible professional fees incurred related to the proposed merger transaction with The Doctors Company (see Note 1 of the Notes to Consolidated Financial Statements). For 2024, transaction-related costs represent the income tax benefit associated with actuarial consulting fees paid in relation to the final determination of contingent consideration associated with the NORCAL acquisition. These costs are not included in a segment as we do not consider these costs in assessing the financial performance of any of our operating or reportable segments. See Note 15 of the Notes to Consolidated Financial Statements for a reconciliation of our segment results to our consolidated results.

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We recognized income tax expense of $21.2 million and $10.3 million in 2025 and 2024, respectively. Our effective tax rate for the year ended December 31, 2025 of 29.4% was different from the statutory federal income tax rate of 21% primarily due to the amount of executive compensation that is in excess of the statutory limitation in 2025, which increased the effective rate 4.5%. Further, our effective tax rate for the year ended December 31, 2025 was impacted by the non-deductible portion of transaction-related costs associated with the proposed merger transaction with The Doctors Company, which accounted for a 2.1% increase in the effective tax rate. Our effective tax rate for the year ended December 31, 2024 of 16.4% differed from the statutory federal income tax rate of 21% primarily due to the benefit of tax positions whose statute of limitations had expired, which accounted for a 4.8% decrease in the effective tax rate. There were no other individually significant items impacting our effective tax rates for 2025 and 2024. See Note 5 of the Notes to Consolidated Financial Statements for a reconciliation of our "expected" consolidated income tax expense to our actual consolidated income tax expense and the associated impact on our consolidated effective tax rate for the years ended December 31, 2025 and 2024.

MD&A history

Prior-year 10-K MD&A spans are extracted from SEC filings with the same bounded parser used for the latest filing. The latest 10-K appears above; prior years are below.

FY 2024 10-K MD&A

SEC filing source: 0001875246-25-000003.

Extracted structurally from real Item 7 body heading to real Item 7A/8 boundary. Confidence: high. Filing date: 2025-02-24. Report date: 2024-12-31.

ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

The following discussion generally focuses on the change in financial condition, results of operations and cash flows for the year ended December 31, 2024 as compared to the year ended December 31, 2023 and should be read in conjunction with the Consolidated Financial Statements and Notes to those statements which accompany this report. For a full discussion of the changes in the financial condition, results of operations and cash flows for the year ended December 31, 2023 as compared to the year ended December 31, 2022, please refer to Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" section of ProAssurance's December 31, 2023 report on Form 10-K.

Throughout the discussion we use certain terms and abbreviations, which can be found in the Glossary of Terms and Acronyms at the beginning of this report. In addition, a glossary of insurance terms and phrases is available on the investor section of our website. Throughout the discussion, references to "ProAssurance," "ProAssurance Group," "PRA," "Company," "organization," "we," "us" and "our" refer to ProAssurance Corporation and its consolidated subsidiaries. The discussion contains certain forward-looking information that involves significant risks, assumptions and uncertainties. As discussed under the heading "Caution Regarding Forward-Looking Statements," our actual financial condition and results of operations could differ significantly from these forward-looking statements.

ProAssurance Overview

ProAssurance Corporation is a holding company for property and casualty insurance companies. Our insurance subsidiaries provide medical professional liability insurance, liability insurance for medical technology and life sciences risks and workers' compensation insurance.

We operate in four segments which are based on our internal management reporting structure for which financial results are regularly evaluated by our Chief Executive Officer (our CODM) to determine resource allocation and assess operating performance: Specialty P&C, Workers' Compensation Insurance, Segregated Portfolio Cell Reinsurance and Corporate. Additional information on our four operating and reportable segments is included in Note 16 of the Notes to Consolidated Financial Statements, Part I and in the Segment Results sections herein that follow.

Growth Opportunities and Outlook

Given the cyclical nature of our insurance operations, our financial objectives span multiple years and we target a dynamic long-term ROE of 700 basis points above the 10-year U.S. Treasury rate, which at December 31, 2024 was approximately 11.6%. To achieve our long-term ROE target, we emphasize rate adequacy, selective underwriting, use of our proprietary data and predictive analytics, effective claims management, operational efficiency gained by leveraging our enhanced scope and scale and prudent investment management. Our overall investment strategy is to focus on maximizing current income from our investment portfolio while maintaining appropriate credit risk, liquidity, duration, portfolio diversification and capital efficiency.

Our focus on ROE and consequently, Non-GAAP operating earnings, means that we place profitability over growth and will make decisions to shrink our businesses if we believe it is in the best long-term interest of the Company. We are focused on strategic initiatives in our insurance operations to support the achievement of our long-term objectives. Over the long-term, we are focused on capturing a larger share of the medical professional liability and workers’ compensation insurance markets in specific geographic areas and sub-sectors if we believe we can do so and achieve our profitability targets; this may lead to top-line growth in the future. Over the Company's history, we also have grown through the acquisition of other insurers, service providers and books of business.

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We operate in very competitive markets and face strong competition from other insurance companies for all of our insurance products. Our Specialty P&C segment includes our MPL insurance operations, which represents the largest product line in our consolidated gross premiums written (70% in 2024). The healthcare market in the U.S. is continuing to consolidate, which brings competitive challenges and opportunities. This consolidation initially took the form of hospitals acquiring physician practices and later the growth of physician groups owned by outside investors. As these trends continue, most physicians no longer practice medicine as owners of an independent practice. Large single and multi-specialty practices often operate in many states. Healthcare delivery settings are changing with the growth of retail delivery by allied healthcare professionals as well as physicians practicing in distributed clinics, pharmacies, large consumer stores and online. The shifts within the healthcare settings continue to impact the overall market for medical professional liability products due to their differing risk profiles. We are focused on serving those segments of the market where we believe we can achieve our profitability objectives over time.

Over the past several years, we also have responded to rising severity in the medical professional liability market driven by social inflation and eroding tort reforms that have been adversely affecting the loss environment. We believe we have stayed ahead of many in the space in achieving rate levels in MPL that outpace severity trends that continue to be challenging. We also continue to forgo renewal and new business opportunities in this loss environment that we believe do not meet our expectation of rate adequacy. We are encouraged that retention of existing insureds is at 84% with strong retention of the more profitable small to midsize accounts, reinforcing our relevance in the market. New business continues to be impacted by our focus on rate adequacy and may continue to trend lower in the near term.

Along with our pricing actions, we remain focused on disciplined underwriting and managing claims to address these market conditions. Innovation tools also continue to enhance our risk selection, pricing decisions and workflows. Work is ongoing to maximize the use of predictive analytics to leverage our extensive data and to identify specific geographic markets and specialty sub-sectors where there are opportunities to write business that has the potential to meet our profitability objectives. We are also committed to ensuring that our insured and distribution partners find us easy to do business with - helping distinguish us in the marketplace.

Our Specialty P&C segment also includes medical technology liability insurance, which contributed 4% to consolidated gross premiums written in 2024. It is less affected by the trends affecting the healthcare sector and has the potential to increase its market share over time.

Our second largest product line is workers' compensation insurance which represents 23% of our consolidated gross premiums written in 2024, including alternative market premiums which are eliminated in consolidation. The workers’ compensation market is highly competitive and multi-line insurers continue to leverage workers’ compensation in their product offerings, which has resulted in a reduction of new business writings. The rates we charge our policyholders remain pressured by the continuation of loss cost decreases in the states within our operating territories, and most states in which we operate have approved additional loss cost decreases for 2025. Our workers' compensation product offerings are designed to provide flexibility in offering solutions to our customers at a competitive price. In addition, we plan to leverage our investment in claims handling and risk management services beginning in the first half of 2025 to support our strong renewal retention and our ability to effectively manage expenses.

We believe our focus on our organization's Mission, Vision and Core Values enhances our market position and differentiates us from other insurers. We will continue to uphold our values of integrity, leadership, relationships and enthusiasm in all of our activities. We will honor these values in the performance of our Mission and pursuit of our Vision. We believe a commitment to our Mission and Vision in the service of our customers will continue to improve retention and add new insureds.

Key Performance Measures

We are committed to disciplined underwriting, pricing and loss reserving practices as well as strategically managing our investment portfolio. We are also committed to maintaining prudent operating and financial leverage. We recognize the importance that our customers and producers place on the financial strength of our insurance subsidiaries, and we manage our business to protect our financial security.

In evaluating our performance, we consider a number of performance measures, including the following:

•The net loss ratio which is calculated as net losses and loss adjustment expenses incurred divided by net premiums earned and is a component of underwriting profitability.

•The underwriting expense ratio which is calculated as underwriting, policy acquisition and operating expenses incurred divided by net premiums earned and is a component of underwriting profitability.

•The combined ratio which is the sum of the net loss ratio and the underwriting expense ratio and measures underwriting profitability.

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•The investment income ratio which is calculated as net investment income divided by net premiums earned and measures the contribution investment earnings provide to our overall profitability.

•The operating ratio which is the combined ratio, less the investment income ratio. This ratio provides the combined effect of underwriting profitability and investment income.

•The effective tax rate which is calculated as total income tax expense (benefit) divided by income (loss) before income taxes.

•Non-GAAP operating income (loss) which is widely used to evaluate performance within the insurance sector. In calculating Non-GAAP operating income (loss), we exclude the effects of items that do not reflect normal operating results. We believe Non-GAAP operating income (loss) presents a useful view of the performance of our core insurance operations; however, it should be considered in conjunction with net income (loss) computed in accordance with GAAP. See a reconciliation to its GAAP counterpart in the Executive Summary of Operations section under the heading “Non-GAAP Financial Measures” that follows.

•ROE which is calculated as net income (loss) divided by the average of beginning and ending shareholders’ equity. This ratio measures our overall after-tax profitability and shows how efficiently capital is being used.

•Non-GAAP operating ROE which is calculated as Non-GAAP operating income (loss) divided by the average of beginning and ending total shareholders’ equity. Non-GAAP operating ROE measures the overall after-tax profitability of our core insurance operations and shows how efficiently capital is being used; however, it should be considered in conjunction with ROE computed in accordance with GAAP. See a reconciliation to its GAAP counterpart in the Executive Summary of Operations section under the heading “Non-GAAP Financial Measures” that follows.

•Book value per share which is calculated as total shareholders’ equity divided by the total number of common shares outstanding at the balance sheet date. This ratio measures the net worth of the Company to shareholders on a per-share basis. Growth in book value per share is an indicator of overall profitability.

•Non-GAAP adjusted book value per share which is a Non-GAAP measure widely used within the insurance sector and is calculated as total shareholders’ equity, excluding AOCI, divided by the total number of common shares outstanding at the balance sheet date. This Non-GAAP calculation measures the net worth of the Company to shareholders on a per share basis excluding AOCI to eliminate the temporary and potentially significant effects of fluctuations in interest rates on our fixed income portfolio; however, it should be considered in conjunction with book value per share computed in accordance with GAAP. See a reconciliation to its GAAP counterpart in the Executive Summary of Operations section under the heading “Non-GAAP Financial Measures” that follows.

In particular, we focus on our combined ratio and investment returns, both of which directly affect our ROE and growth in our book value per share.

Critical Accounting Estimates

Our Consolidated Financial Statements are prepared in conformity with GAAP. Preparation of these financial statements requires us to make estimates and assumptions that affect the amounts we report on those statements. We evaluate these estimates and assumptions on an ongoing basis based on current and historical developments, market conditions, industry trends and other information that we believe to be reasonable under the circumstances. We can make no assurance that actual results will conform to our estimates and assumptions; reported results of operations may be materially affected by changes in these estimates and assumptions.

Management considers the following accounting estimates to be critical because they involve significant judgment by management and those judgments could result in a material effect on our financial statements.

Reserve for Losses and Loss Adjustment Expenses

The largest component of our liabilities is our reserve for losses and loss adjustment expenses ("reserve for losses" or "reserve"), and the largest component of expense for our operations is incurred losses and loss adjustment expenses (also referred to as “losses and loss adjustment expenses,” “incurred losses,” “losses incurred” and “losses”). Incurred losses reported in any period reflect our estimate of losses incurred related to the premiums earned in that period as well as any changes to our previous estimate of the reserve required for prior periods.

As of December 31, 2024, our reserve is comprised almost entirely of long-tail exposures. The estimation of long-tailed losses is inherently complex and is subject to significant judgment on the part of management. Due to the nature of our claims, our loss costs, even for claims with similar characteristics, can vary significantly depending upon many factors, including but not limited to the specific characteristics of the claim and the manner or jurisdiction in which the claim is resolved. Long-tailed insurance is characterized by the extended period of time typically required both to assess the viability of a claim and potential

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damages, if any, and to reach a resolution of the claim. The claims resolution process may extend to more than five years. The combination of continually changing conditions and the extended time required for claim resolution results in a loss cost estimation process that requires actuarial skill and the application of significant judgment, and such estimates require periodic modification.

Our reserve is established by management after taking into consideration a variety of factors including premium rates, historical paid and incurred loss development trends and our evaluation of the current loss environment including frequency, severity, expected effects of inflation (monetary, social and medical), general economic and social trends, and the legal and political environment. We also take into consideration the conclusions reached by our internal and consulting actuaries. We update and review the data underlying the estimation of our reserve for losses each reporting period and make adjustments to loss estimation assumptions that we believe best reflect emerging data. Both our internal and consulting actuaries perform an in-depth review of our reserve for losses on at least a semi-annual basis using the loss and exposure data of our insurance subsidiaries.

We partition our reserves by accident year, which is the year in which the claim becomes our liability. For claims-made policies, the insured event generally becomes a liability when the event is first reported to us. For occurrence policies, the insured event becomes a liability when the event takes place. For retroactive coverages, the insured event becomes a liability at inception of the underlying contract. As claims are incurred (reported) and claim payments are made, they are aggregated by accident year for analysis purposes. We also partition our reserves by reserve type: case reserves and IBNR reserves. Case reserves are established by our claims departments based upon the particular circumstances of each reported claim and represent our estimate of the future loss costs (often referred to as expected losses) that will be paid on reported claims. Case reserves are decremented as claim payments are made and are periodically adjusted upward or downward as estimates regarding the amount of future losses are revised; reported loss for an individual claim is the case reserve at any point in time plus the claim payments that have been made to date. IBNR reserves are estimated by accident year by our actuarial department and represent our estimate in the aggregate of future development on losses that have been reported to us and our estimate of losses that have been incurred but not reported to us.

Our reserving process can be broadly grouped into three areas: the establishment of the reserve for the current accident year (the initial reserve), the re-estimation of the reserve for prior accident years (development of prior accident years) and the establishment of the initial reserve for risks assumed in business combinations, applicable only in periods in which acquisitions occur (the acquired reserve). A summary of the activity in our net reserve for losses during 2024 and 2023 is provided under the heading "Losses" in the Liquidity and Capital Resources and Financial Condition section that follows.

Current Accident Year - Initial Reserve

Considerable judgment is required in establishing our initial reserve for any current accident year period, as there is limited data available upon which to base our estimate (see further discussion that follows under the heading "Use of Judgment"). Our process for setting an initial reserve considers the unique characteristics of each product, but in general we rely heavily on the loss assumptions that were used to price business, as our pricing reflects our analysis of loss costs that we expect to incur relative to the insurance product being priced.

Specialty P&C Segment. Loss costs within this segment are impacted by many factors including but not limited to the nature of the claim, including whether or not the claim is an individual or a mass tort claim, the personal situation of the claimant or the claimant's family, the outcome of jury trials including the impacts of social inflation, the legislative and judicial climate where any potential litigation may occur, general economic and social trends and the trend of healthcare costs. Within our Specialty P&C segment, for our professional liability business (86% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2024; predominately comprised of our MPL products), we set an initial reserve using a loss ratio approach based upon our evaluation of the current loss environment including frequency, severity, monetary inflation, social inflation and legal trends. See further discussion in our Segment Results - Specialty Property & Casualty section that follows under the heading "Losses and Loss Adjustment Expenses."

The risks insured in our Medical Technology Liability business (3% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2024) are more varied, and policies are individually priced based on the risk characteristics of the policy and the account. The insured risks range from startup operations to large multinational entities, and the larger entities often have significant deductibles or self-insured retentions. Reserves are established using our most recently developed actuarial estimates of losses expected to be incurred based on factors which include results from prior analysis of similar business, industry indications, observed trends and judgment. Claims in this line of business primarily involve bodily injury to individuals and are affected by factors similar to those of our MPL line of business. For the Medical Technology Liability business, we also establish an initial reserve using a loss ratio approach, including a provision in consideration of historical loss volatility that this line of business has exhibited.

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Workers' Compensation Insurance Segment. Many factors affect the ultimate losses incurred for our workers' compensation coverages (6% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2024) including but not limited to the type and severity of the injury, the age, health and occupation of the injured worker, the estimated length of disability, medical treatment and related costs, and the jurisdiction and workers' compensation laws of the state of the injury occurrence.

We use various actuarial methodologies in developing our workers’ compensation reserve, combined with a review of the payroll exposure base. For the current accident year, given the lack of seasoned information, the different actuarial methodologies produce results with significant variability; therefore, more emphasis is placed on supplementing results from the actuarial methodologies with trends in exposure base, medical expense inflation, general inflation, severity and claim counts, among other things, to select an ultimate loss indication.

Segregated Portfolio Cell Reinsurance Segment. The factors that affect the ultimate losses incurred for the workers' compensation and medical professional liability coverages assumed by the SPCs at Inova Re and Eastern Re (2% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2024) are consistent with that of our Workers’ Compensation Insurance and Specialty P&C segments, respectively.

Development of Prior Accident Years

In addition to setting the initial reserve for the current accident year, we reassess the amount of reserve required for prior accident years each period.

The foundation of our reserve re-estimation process is an actuarial analysis that is performed by both our internal and consulting actuaries. This detailed analysis projects ultimate losses based on partitions which include line of business, geography, coverage layer and accident year. The procedure uses the most representative data for each partition, capturing its unique patterns of development and trends. We believe that the use of consulting actuaries provides an independent view of our loss data as well as a broader perspective on industry loss trends.

The analyses performed by our internal actuarial team and the consulting actuaries analyzes each partition of our business in a variety of ways and uses multiple actuarial methodologies in performing these analyses, including:

•Bornhuetter-Ferguson (Paid and Reported) Method

•Paid Development Method

•Reported (Incurred) Development Method

•Average Paid Value Method

•Average Reported Value Method

A brief description of each method follows.

Bornhuetter-Ferguson Method. We use both the Paid and the Reported Bornhuetter-Ferguson Methods. The Paid Method assigns partial weight to initial expected losses for each accident year (initial expected losses being the first established case and IBNR reserves for a specific accident year) and partial weight to paid to date losses. The Reported Method assigns partial weight to the initial expected losses and partial weight to current reported losses. The weights assigned to the initial expected losses decrease as the accident year matures.

Paid Development and Reported (Incurred) Development Methods. These methods use historical, cumulative losses (paid losses for the Paid Development Method, reported losses for the Reported (Incurred) Development Method) by accident year and develop those actual losses to estimated ultimate losses based upon the assumption that each accident year will develop to estimated ultimate cost in a manner that is analogous to prior years, adjusted as deemed appropriate for the expected effects of known changes in the claim payment environment (and case reserving environment for the Reported (Incurred) Development Method); and to the extent necessary, supplemented by analyses of the development of broader industry data.

Average Paid Value and Average Reported Value Methods. In these methods, average claim cost data (paid claim cost for the Average Paid Value Method and reported claim cost for the Reported Value Method) is developed to an ultimate average cost level by report year based on historical data. Claim counts are similarly developed to an ultimate count level. The average claim cost (after rounding and adjustment, if necessary, to accommodate report year data that is not considered to be predictive) is then multiplied by the ultimate claim counts by report year to derive ultimate loss and ALAE.

We use various actuarial methods in the process of setting reserves. Each actuarial method generally returns a different value, and for the more recent accident years the variations among the different methodologies can be significant. Generally, methods such as the Bornhuetter-Ferguson Method are used on more recent accident years where we have less data on which to base our analysis. As time progresses and we have an increased amount of data for a given accident year, we begin to give more confidence to the development and average methods, as these methods typically rely more heavily on our own historical data. These methods emphasize different aspects of loss reserve estimation and provide a variety of perspectives for our decisions.

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Certain of the methodologies utilized to estimate the ultimate losses for each partition of our reserves consider the actual amounts paid. Paid data is particularly influential when a large portion of known claims have been closed, as is the case for older accident years. In selecting a point estimate for each partition, management considers the extent to which trends are emerging consistently for all partitions and known industry trends. Thus, actual, rather than estimated severity trends are given more consideration. If actual severity trends are lower than those estimated at the time that reserves were previously established, the recognition of favorable development is indicated. This is particularly true for older accident years where our actuarial methodologies give more weight to actual loss costs (severity).

The various actuarial methods discussed above are applied in a consistent manner from period to period. For each partition of our reserves, we evaluate the results of the various methods, along with the supplementary statistical data regarding such factors as closed with and without indemnity ratios, claim severity trends, the expected duration of such trends, changes in the legal and legislative environment and the current economic environment to develop a point estimate based upon management's judgment and past experience. The series of selected point estimates is then combined to produce an overall point estimate for ultimate losses.

We utilize the selected point estimates of ultimate losses to develop estimates of ultimate losses recoverable from reinsurers, based on the terms and conditions of our reinsurance agreements. An overall estimate of the amount receivable from reinsurers is determined by combining the individual estimates. Our net reserve estimate is the gross reserve point estimate less the estimated reinsurance recovery.

For our Workers’ Compensation Insurance segment and for the workers' compensation exposures in our Segregated Portfolio Cell Reinsurance segment, we utilize the Reported (Incurred) Development Method, Paid Development Method and Bornhuetter-Ferguson Method, to develop our reserve for each accident year. The actuarial review includes the stratification of claims data (lost time claims, medical only claims) using different variations that allow us to identify trends that may not be readily identifiable if the data was evaluated only in the aggregate. Reported and paid loss development factors are key assumptions in the reserve estimation process and are influenced by our historical reported and paid loss development patterns. As accident years mature, the various actuarial methodologies produce more consistent loss estimates.

Acquired Reserve

The acquisition of NORCAL on May 5, 2021 increased our gross reserves by $1.2 billion which was the fair value of NORCAL's gross loss reserve at the time of acquisition. The fair value estimate of NORCAL's gross reserve for losses and loss adjustment expenses was based on three components: an actuarial estimate of the expected future net cash flows, a reduction to those cash flows for the time value of money determined utilizing the U.S. Treasury Yield Curve and a risk margin adjustment to reflect the net present value of profit that an investor would demand in return for the assumption of the development risk associated with the reserve. The fair value of NORCAL's gross reserve, including the risk margin adjustment, exceeded the actuarial estimate of NORCAL’s undiscounted gross loss reserve by approximately $42.2 million as of May 5, 2021. This fair value adjustment was recorded to the reserve for losses and loss adjustment expenses and will be amortized over a period utilizing loss payment patterns as a reduction to prior accident year net losses and loss adjustment expenses. We also recorded other adjustments to NORCAL’s reserve as a result of purchase accounting including negative VOBA on NORCAL’s assumed unearned premium and assumed DDR reserve.

Use of Judgment/Variability of Loss Reserves

The process of estimating reserves involves a high degree of judgment and is subject to a number of variables. These variables can be affected by both views of internal and external events, such as changes in views of monetary and social inflation, legal trends and legislative changes, as well as differentiating views of individuals involved in the reserve estimation process, among others. We continually refine our estimates in a regular, ongoing process as historical loss experience develops and additional claims are reported and settled. Our objective is to consider all significant facts and circumstances known at the time.

Our loss reserves may be impacted by social inflation, which is generally described as the rising costs of insurance claims resulting from factors including, but not limited to, increasing litigation, broader definitions of liability, more plaintiff-friendly legal decisions, jury behavior, third-party litigation financing, and larger compensatory jury awards and non-economic damages. These factors could lead to greater than anticipated claims and claim handling expenses which could exceed our established reserves causing us to increase our loss reserves.

The effects of monetary and medical inflation could cause the cost of claims to rise in the future. Our loss reserves include assumptions about future payments for settlement of claims and claims handling expenses, such as medical treatments and litigation costs. For our workers' compensation reserves, healthcare wage inflation and medical advancements may also increase the cost of claims. To the extent inflation causes these costs to increase above reserves established for these claims, we will be required to increase our loss reserves with a corresponding reduction in our financial results in the period in which the need for additional reserves is identified.

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MPL. Over the past several years the most influential factor affecting the analysis of our MPL reserves and the related development recognized has been an observed increase in claim severity for the broader medical professional liability industry as well as higher initial loss expectations on incurred claims. The severity trend is an explicit component of our pricing models and directly impacts the reserving process. Our estimate of this trend and our expectations about changes in this trend impact a variety of factors, from the selection of expected loss ratios to the ultimate point estimates established by management.

Because of the implicit and wide-ranging nature of severity trend assumptions on the loss reserving process, it is not practical to specifically isolate the impact of changing severity trends. However, because severity is an explicit component of our MPL pricing process we can better isolate the impact that changing severity can have on our loss costs and loss ratios in regards to our pricing models for this business component. Our current MPL pricing models assume severity trends in the range of 3% to 6% depending on state, territory and specialty. In some portions of our MPL business, we have observed and reflected higher severity trends in our estimates of losses and loss adjustment expenses.

Due to the long-tailed nature of our claims and the previously discussed historical volatility of loss costs, selection of a severity trend assumption is a subjective process that is inherently likely to prove inaccurate over time. Given the long tail and volatility, we are generally cautious in making changes to the severity assumptions within our pricing models. All open claims and accident years are generally impacted by a change in the severity trend, which compounds the effect of such a change.

Although the future degree and impact of the ultimate severity trend remains uncertain due to the long-tailed nature of our business, we have given consideration to observed loss costs in setting our rates. For our MPL business, this practice has recently resulted in rate increases reflecting the rising loss cost environment, and we anticipate further renewal pricing increases due to increasing loss severity.

Workers' Compensation. In our workers’ compensation business, severity is not an explicit component of our pricing process, as loss costs are established by the states in which we operate. We do, however, have the ability in certain states to apply for increases in our loss cost multipliers to adjust for company specific loss experience that is higher than state loss cost changes. In our reserving process, we consider the loss severity trends in evaluating both our current and expected loss development. Historically, we have been able to minimize the impact of higher severity trends as a result of our early intervention and case management strategies in our claims process, which results in claims being resolved more quickly than the industry norm. However, in the second half of 2023, we observed higher than expected loss trends in our average cost per claim which we primarily attribute to increased medical costs driven by wage inflation and medical advancements. In response to these trends, we increased both our current accident year loss ratio and prior year reserves in 2023. While we continue to observe, and therefore reflect, higher medical loss cost trends, we have seen these trends begin to moderate in 2024, including a reduction in the 2024 average cost per claim.

As previously noted, the number of data points and variables considered and the subjective process followed in establishing our loss reserve makes it impractical to isolate individual variables and demonstrate their impact on our estimate of loss reserves. However, to provide a better understanding of the potential variability in our reserves, we have modeled implied reserve ranges around our single point net reserve estimates for our various lines of business assuming different confidence levels. The ranges have been developed by aggregating the expected volatility of losses across partitions of our business to obtain a consolidated distribution of potential reserve outcomes. The aggregation of this data takes into consideration correlations among our geographic and specialty mix of business. The result of the correlation approach to aggregation is that the ranges are narrower than the sum of the ranges determined for each partition.

We have used this modeled statistical distribution to calculate an 80% and 60% confidence interval for the potential outcome of our consolidated net reserve for losses. The high and low end points of the distributions are as follows:

Low End PointCarried Net ReserveHigh End Point
80% Confidence Level$2.085 billion$2.849 billion$3.726 billion
60% Confidence Level$2.302 billion$2.849 billion$3.344 billion

Any change in our estimate of net ultimate losses for prior years is reflected in net income (loss) in the period in which such changes are made. Due to the size of our consolidated reserve for losses and the large number of claims outstanding at any point in time, even a small percentage adjustment to our total reserve estimate could have a material effect on our results of operations for the period in which the adjustment is made.

Loss Development by Line of Business

Professional Liability

Our professional liability business is primarily compromised of our MPL line of business. We also provide professional liability coverage to attorneys and their firms in select areas of practice. As a result of the higher severity environment, we saw

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our closed-with-indemnity-payment ratio (i.e., the number of suits closed with an indemnity or loss payment as compared to the total number of closed suits) for our claims increase from 28% in 2015 to 35% in 2024.

The following table presents additional information about the loss development for our professional liability line of business, excluding loss development for MPL coverages assumed by the SPCs at Inova Re and Eastern Re. Furthermore, loss development for our professional liability line of business for the years ended December 31, 2024, 2023 and 2022 excludes the amortization of purchase accounting fair value adjustments.

($ in thousands)202420232022
Accident YearsEstimated Ultimate Losses, Net of Reinsurance, December 31, 2024Reserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims Closed
2024$583,875N/A24.5%N/AN/AN/AN/A
2023$643,369$6,14652.7%N/A24.7%N/AN/A
2022$613,710$(1,362)70.8%$(10,151)55.0%N/A26.9%
2021$680,860$(10,207)82.1%$(11,690)71.6%$(5,754)52.9%
2020$868,228$(14,686)89.3%$44,06182.5%$(17,597)66.7%
2019$875,608$(3,536)93.7%$5,22090.4%$20,28583.5%
2018$852,679$2,78296.3%$41393.6%$4,49189.5%
2017$718,374$2,27396.5%$(8,265)95.4%$(10,261)93.3%
2016$735,957$(2,555)91.7%$(2,922)92.3%$1,64291.0%
2015$661,638$(7,445)99.4%$(3,825)98.9%$5,19098.1%
Prior to 2015$13,266,105$(5,336)$(3,232)$(11,997)

•The loss environment in our MPL line of business continues to be challenging in many jurisdictions, as claim costs are pressured by social inflation and higher than anticipated loss severity trends that started to reemerge in the fourth quarter of 2022. We continue to monitor the impact that these trends have on our open case reserves and prior accident year development. While higher loss severity trends remained challenging in 2024, we recognized net favorable reserve development of $33.9 million during the year ended December 31, 2024 reflecting overall favorable trends in claim closing patterns relative to expectations, principally related to accident years 2019 through 2021.

•Net unfavorable development recognized during 2023 principally related to accident years 2019 and 2020. Net unfavorable reserve development recognized in 2023 was driven by the strengthening of case reserves related to four large claims resulting in unfavorable development of $10.1 million in our MPL line of business during the first quarter of 2023, primarily related to NORCAL's accident years 2016 and 2020, partially offset by $0.5 million of net favorable reserve development recognized during the fourth quarter of 2023, primarily related to accident years 2018 and prior in our legacy book. Further, we recognized unfavorable development in the fourth quarter of 2023 in NORCAL’s 2020 and prior accident year reserves which was entirely offset by favorable development recognized in NORCAL’s 2021 and 2022 accident year reserves since acquisition. These adjustments to NORCAL’s reserves had no impact to the segment’s net losses.

•Development recognized during 2022 principally related to accident years 2017, 2020 and 2021. Net favorable development recognized in 2022 included favorable development related to NORCAL's 2021 accident year. Net favorable prior accident year reserve development recognized in 2022 was partially offset by unfavorable development recognized in our MPL line of business, excluding NORCAL, driven by higher than anticipated loss severity trends, which emerged primarily in the fourth quarter of 2022. In addition, we recognized favorable prior year reserve development of $9.0 million in 2022 related to the 2020 accident year associated with the remaining reduction to our previous COVID-19 IBNR reserve due to the fact that early first notices of potential claims did not turn into claims.

•Not included in the table above, is $5.3 million, $8.3 million and $10.8 million of amortization of the purchase accounting fair value adjustment on NORCAL's assumed net reserve and amortization of the negative VOBA associated with NORCAL's DDR reserve which is recorded as a reduction to prior accident year net losses and loss adjustment expenses in 2024, 2023 and 2022, respectively.

•Not included in the above table is $0.3 million, $1.3 million and $0.7 million of unfavorable development recognized in 2024, 2023 and 2022, respectively, in our Segregated Portfolio Cell Reinsurance segment related to the medical professional liability coverages assumed by the SPCs at Inova Re and Eastern Re, as previously discussed.

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Medical Technology Liability

The nature of the risks insured and volatility of the loss experience in the Medical Technology Liability line of business has produced more variable loss development, as presented in the following table:

($ in thousands)202420232022
Accident YearsEstimated Ultimate Losses, Net of Reinsurance, December 31, 2024Reserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims Closed
2024$18,587N/A49.8%N/AN/AN/AN/A
2023$17,255$(1,609)55.3%N/A28.0%N/AN/A
2022$14,093$(2,141)80.2%$(1,448)59.6%N/A16.8%
2021$13,334$83677.2%$(1,647)73.0%$(2,759)53.3%
2020$10,028$(1,098)84.0%$(1,442)80.1%$(1,921)70.6%
2019$12,528$(953)62.2%$1,23561.3%$(1,337)55.3%
2018$9,239$18689.5%$49989.5%$(252)86.4%
2017$6,846$(65)99.0%$(1,056)99.0%$1,95097.1%
2016$8,802$17399.5%$(517)99.5%$53598.4%
2015$8,278$35999.4%$70399.4%$(767)97.6%
Prior to 2015$606,516$(188)$(326)$(449)

•Approximately $3.8 million of the $4.5 million total net favorable development recognized in 2024 related to the 2022 and 2023 accident years. The development for the 2022 and 2023 accident years represents a 10.7% reduction to the ultimates established for those reserves at December 31, 2023.

•Approximately $4.5 million of the $4.0 million total net favorable development recognized in 2023 related to the 2020 through 2022 accident years. The development for the 2020 through 2022 accident years represents a 10.2% reduction to the ultimates established for those reserves at December 31, 2022.

•Approximately $6.3 million of the $5.0 million total net favorable development recognized in 2022 related to the 2018 through 2021 accident years. The development for the 2018 through 2021 accident years represents a 11.7% reduction to the ultimates established for those reserves at December 31, 2021.

•In 2024, 2023 and 2022, the development was largely attributable to favorable results from claims closed during the year. As time has elapsed we have recognized that actual loss experience has on average been better than estimated. We have been cautious in recognizing the improvement, but as claims have matured and claims are closed or have become more certain for the remaining open claims, we have revised reserve estimates. We believe the need for a cautious approach is required as outcomes are uncertain and results can be significantly affected by outcomes for a small number of cases.

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Workers' Compensation

Claims in our workers’ compensation line of business have historically closed at a faster rate than in our MPL or Medical Technology Liability lines of business. This faster disposition rate, along with a lower net retention after the application of reinsurance, has resulted in less volatility in loss estimates on a net basis. However, a change in the number of individually-severe claims can create volatility in a given accident year. The following table presents additional information about the loss development for our workers' compensation line of business:

($ in thousands)202420232022
Accident YearsEstimated Ultimate Losses, Net of Reinsurance, December 31, 2024Reserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims Closed
2024$150,956N/A43.0%N/AN/AN/AN/A
2023$147,742$(1,576)79.5%N/A40.3%N/AN/A
2022$151,554$(116)91.3%$9,01681.3%N/A39.8%
2021$145,869$(1,255)95.7%$1,21792.8%$67582.6%
2020$135,155$(255)98.2%$(2,318)96.7%$(3,348)93.8%
2019$146,722$(1,183)98.3%$(2,119)97.9%$(4,143)96.2%
2018$156,067$(1,266)98.5%$(1,819)98.1%$(410)97.2%
2017$125,135$(479)98.8%$(711)98.7%$(3,209)98.2%
2016$107,362$(13)99.1%$(231)99.0%$(2,179)98.5%
2015$115,776$(269)99.3%$(232)99.2%$(1,285)98.9%
Prior to 2015$892,265$2,826$1,211$(1,107)

•In 2024, we recognized $0.5 million of net favorable development in our Workers' Compensation Insurance segment and we recognized $3.1 million of net favorable development in our Segregated Portfolio Cell Reinsurance segment related to workers' compensation business.

•In 2023, we recognized $9.3 million of net unfavorable development in our Workers' Compensation Insurance segment and $5.3 million of net favorable development in our Segregated Portfolio Cell Reinsurance segment related to workers' compensation business. The net unfavorable prior year reserve development in 2023 reflects higher than expected average claim costs primarily in the 2022 accident year and higher than expected loss experience primarily attributable to a large claim from the 1997 accident year.

•In 2022, we recognized $7.0 million of net favorable development in our Segregated Portfolio Cell Reinsurance segment related to workers' compensation business and $8.0 million of net favorable development in our Workers' Compensation Insurance segment.

Reinsurance

We use insurance and reinsurance (collectively, “reinsurance”) to provide capacity to write larger limits of liability, to provide reimbursement for losses incurred under the higher limit coverages we offer, to provide protection against losses in excess of policy limits and, in the case of risk sharing arrangements, to align our objectives with those of our strategic business partners and to provide custom insurance solutions for large customer groups. The purchase of reinsurance does not relieve us from the ultimate risk on our policies; however, it does provide reimbursement for certain losses we pay.

We make a determination of the amount of insurance risk we choose to retain based upon numerous factors, including our risk tolerance and the capital we have to support it, the price and availability of reinsurance, the volume of business, our level of experience with a particular set of exposures and our analysis of the potential underwriting results. We purchase excess of loss reinsurance to limit the amount of risk we retain and we do so from a number of companies to mitigate concentrations of credit risk. As of December 31, 2024, there is no reinsurer, on an individual basis, for which our recoverables for both paid and unpaid claims (net of amounts due to the reinsurer) and our prepaid balances are more than $55 million, in the aggregate. We utilize reinsurance brokers to assist us in the placement of these reinsurance programs and in the analysis of the credit quality of our reinsurers. The determination of which reinsurers we choose to do business with is based upon an evaluation of their then current financial strength, rating, stability and claims payment practices.

We evaluate each of our ceded reinsurance contracts at inception to confirm that there is sufficient risk transfer to allow the contract to be accounted for as reinsurance under current accounting guidance. At December 31, 2024, all ceded contracts were accounted for as risk transferring contracts.

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Our receivable from reinsurers on unpaid losses and loss adjustment expenses represents our estimate of the amount of our reserve for losses that will be recoverable under our reinsurance programs. We base our estimate of funds recoverable upon our expectation of ultimate losses and the portion of those losses that we estimate to be allocable to reinsurers based upon the terms and conditions of our reinsurance agreements. Our assessment of the collectability of the recorded amounts receivable from reinsurers considers the payment history of the reinsurer, publicly available financial and rating agency data, our interpretation of the underlying contracts and policies and responses by reinsurers.

Given the uncertainty inherent in our estimates of losses and related amounts recoverable from reinsurers, these estimates may vary significantly from the ultimate outcome.

Under the terms of certain of our reinsurance agreements, the amount of premium that we cede to our reinsurers is based in part on the losses we recover under the agreements. Therefore, we make an estimate of premiums ceded under these reinsurance agreements subject to certain minimums and maximums. Any adjustments to our estimates of losses recoverable under our reinsurance agreements or the premiums owed under our agreements are reflected in current operations. Due to the size of our reinsurance balances, an adjustment to these estimates could have a material effect on our results of operations for the period in which the adjustment is made.

Our reinsurance receivables are exposed to credit losses but to date have not experienced any significant amount of credit losses. To partially mitigate our exposure to credit losses, reinsurance receivables totaling approximately $145.5 million were collateralized by letters of credit or funds withheld as of December 31, 2024. We measure expected credit losses on our reinsurance receivables on a collective basis when similar risk characteristics exist or on an individual basis if we determine a receivable does not share similar risk characteristics. We measure expected credit losses associated with our reinsurance receivables (related to both paid and unpaid losses) at the consolidated level as our reinsurance receivables share similar risk characteristics including type of financial asset, type of industry and similar historical and expected credit loss patterns. We measure expected credit losses over the average contractual term of our reinsurance receivables utilizing a loss rate method. Historical internal credit loss experience is the basis for our assessment of expected credit losses; however, we may also consider historical credit loss information from external sources. We also consider reasonable and supportable forecasts of future economic conditions in our estimate of expected credit losses. Expected credit losses associated with our reinsurance receivables (related to both paid and unpaid losses) were nominal in amount as of December 31, 2024 and 2023. No reinsurance balances were written off for credit reasons during the years ended December 31, 2024 or 2023. Should our expected credit loss analysis or other facts or circumstances lead us to believe that any reinsurer may not meet its obligations to us, adjustments to the allowance for expected credit losses or to reinsurance receivables would be reflected in current operations. Such an adjustment has the potential to be material to the results of operations in the period in which it is recorded; however, we would not expect such an adjustment to have a material effect on our capital position or our liquidity. For further information on our allowance for expected credit losses related to our receivables from reinsurers see Note 1 of the Notes to Consolidated Financial Statements.

Investment Valuations

We record the majority of our investments at fair value as shown in the table below. At December 31, 2024, the distribution of our investments based on GAAP fair value hierarchies (levels) was as follows:

Distribution by GAAP Fair Value Hierarchy
Level 1Level 2Level 3Not CategorizedTotal Investments
Investments recorded at:
Fair value7%83%2%5%97%
Other valuations3%
Total Investments100%

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. All of our fixed maturity and equity investments are carried at fair value. The fair value of our short-term securities approximates the cost of the securities due to their short-term nature.

Because of the number of securities we own and the complexity of developing accurate fair values, we utilize multiple independent pricing services to assist us in establishing the fair value of individual securities. The pricing services provide fair values based on exchange-traded prices, if available. If an exchange-traded price is not available, the pricing services, if possible, provide a fair value that is based on multiple broker/dealer quotes or that has been developed using pricing models. Pricing models vary by asset class and utilize currently available market data for securities comparable to ours to estimate a fair value for our securities. The pricing services scrutinize market data for consistency with other relevant market information before including the data in the pricing models. The pricing services disclose the types of pricing models used and the inputs

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used for each asset class. Determining fair values using these pricing models requires the use of judgment to identify appropriate comparable securities and to choose a valuation methodology that is appropriate for the asset class and available data.

The pricing services provide a single value per instrument quoted. We review the values provided for reasonableness each quarter by comparing market yields generated by the supplied value versus market yields observed in the marketplace. We also compare yields indicated by the provided values to appropriate benchmark yields and review for values that are unchanged or that reflect an unanticipated variation as compared to prior period values. We utilize a primary pricing service for each security type and compare provided information for consistency with alternate pricing services, known market data and information from our own trades, considering both values and valuation trends. We also review weekly trades versus the prices supplied by the services. If a supplied value appears unreasonable, we discuss the valuation in question with the pricing service and make adjustments if deemed necessary. Historically our review has not resulted in any material changes to the values supplied by the pricing services. The pricing services do not provide a fair value unless an exchange-traded price or multiple observable inputs are available. As a result, the pricing services may provide a fair value for a security in some periods but not others, depending upon the level of recent market activity for the security or comparable securities.

Level 1 Investments

Fair values for a majority of our equity securities and portions of our short-term and convertible securities are determined using exchange-traded prices. There is little judgment involved when fair value is determined using an exchange-traded price. In accordance with GAAP, we classify securities valued using an exchange-traded price as Level 1 securities.

Level 2 Investments

Most fixed income securities do not trade daily; thus, exchange-traded prices are generally not available for these securities. However, market information (often referred to as observable inputs or market data, including but not limited to, last reported trade, non-binding broker quotes, bids, benchmark yield curves, issuer spreads, two-sided markets, benchmark securities, offers and recent data regarding assumed prepayment speeds, cash flow and loan performance data) is available for most of our fixed income securities. We determine fair value for a large portion of our fixed income securities using available market information. In accordance with GAAP, we classify securities valued based on multiple market observable inputs as Level 2 securities.

Level 3 Investments

When a pricing service does not provide a value for one of our fixed maturity securities, management estimates fair value using either a single non-binding broker quote or pricing models that utilize market based assumptions which have limited observable inputs. The process involves significant judgment in selecting the appropriate data and modeling techniques to use in the valuation process. In accordance with GAAP, we classify securities valued using limited observable inputs as Level 3 securities.

Fair Values Not Categorized

We hold interests in certain investment funds, primarily LPs/LLCs, which measure fund assets at fair value on a recurring basis and provide us with a NAV for our interest. As a practical expedient, we consider the NAV provided to approximate the fair value of our interest. In accordance with GAAP, we do not categorize these investments within the fair value hierarchy.

Nonrecurring Fair Value Measurements

We measure the fair value of certain assets on a nonrecurring basis when events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. These assets include investments carried principally at cost, investments in tax credit partnerships, fixed assets, goodwill and other intangible assets. These assets would also include any equity method investments that do not provide a NAV. During the third quarter of 2023, we recognized a nonrecurring fair value measurement related to the goodwill in our Workers' Compensation Insurance reporting unit with a carrying value of $44.1 million prior to the fair value measurement. This nonrecurring fair value measurement resulted in the goodwill being written down to its implied fair value of zero resulting in an impairment of goodwill of $44.1 million (see additional information on our goodwill impairment in Note 6 of the Notes to the Consolidated Financial Statements). The fair value measurement used inputs that were non-observable and, as such, was categorized as a Level 3 valuation. We did not have any other assets or liabilities that were measured at fair value on a nonrecurring basis at December 31, 2024 or December 31, 2023.

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Investments - Other Valuation Methodologies

Certain of our investments, in accordance with GAAP for the type of investment, are measured using methodologies other than fair value. At December 31, 2024, these investments represented approximately 3% of total investments and are detailed in the following table. Additional information about these investments is provided in Note 2 and Note 3 of the Notes to Consolidated Financial Statements.

(In millions)Carrying ValueGAAP Measurement Method
Other investments:
Other, principally FHLB capital stock$5.2Principally Cost
Investment in unconsolidated subsidiaries:
Investments in tax credit partnerships0.2Equity
Equity method investments, primarily LPs/LLCs33.0Equity
33.2
BOLI80.2Cash surrender value
Total investments - Other valuation methodologies$118.6

Impairments

We evaluate our available-for-sale investment securities, which at December 31, 2024 and December 31, 2023 consisted entirely of fixed maturity securities, on at least a quarterly basis for the purpose of determining whether declines in fair value below recorded cost basis represent an impairment loss. We consider a credit-related impairment loss to have occurred:

•if there is intent to sell the security;

•if it is more likely than not that the security will be required to be sold before full recovery of its amortized cost basis; or

•if the entire amortized basis of the security is not expected to be recovered.

The assessment of whether the amortized cost basis of a security is expected to be recovered requires management to make assumptions regarding various matters affecting future cash flows. The choice of assumptions is subjective and requires the use of judgment. Actual credit losses experienced in future periods may differ from management’s current estimates of those credit losses. Methodologies used to estimate the present value of expected cash flows are:

The estimate of expected cash flows is determined by projecting a recovery value and a recovery time frame and assessing whether further principal and interest will be received. We consider various factors in projecting recovery values and recovery time frames, including the following:

•third-party research and credit rating reports;

•the current credit standing of the issuer, including credit rating downgrades, whether before or after the balance sheet date;

•the extent to which the decline in fair value is attributable to credit risk specifically associated with the security or its issuer;

•internal assessments and the assessments of external portfolio managers regarding specific circumstances surrounding an investment, which indicate the investment is more or less likely to recover its amortized cost than other investments with a similar structure;

•for asset-backed securities, the origination date of the underlying loans, the remaining average life, the probability that credit performance of the underlying loans will deteriorate in the future and our assessment of the quality of the collateral underlying the loan;

•failure of the issuer of the security to make scheduled interest or principal payments;

•any changes to the rating of the security by a rating agency;

•recoveries or additional declines in fair value subsequent to the balance sheet date;

•adverse legal or regulatory events;

•significant deterioration in the market environment that may affect the value of collateral (e.g., decline in real estate prices);

•significant deterioration in economic conditions; and

•disruption in the business model resulting from changes in technology or new entrants to the industry.

If deemed appropriate and necessary, a discounted cash flow analysis is performed to confirm whether a credit loss exists and, if so, the amount of the credit loss. We use the single best estimate approach for available-for-sale debt securities and consider all reasonably available data points, including industry analyses, credit ratings, expected defaults and the remaining

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payment terms of the debt security. For fixed rate available-for-sale debt securities, cash flows are discounted at the security's effective interest rate implicit in the security at the date of acquisition. If the available-for-sale debt security’s contractual interest rate varies based on subsequent changes in an independent factor, such as an index or rate, for example, the prime rate, the SOFR, or the U.S. Treasury bill weekly average, that security’s effective interest rate is calculated based on the factor as it changes over the life of the security. If we intend to sell a debt security or believe we will more likely than not be required to sell a debt security before the amortized cost basis is recovered, any existing allowance will be written off against the security's amortized cost basis, with any remaining difference between the debt security's amortized cost basis and fair value recognized as an impairment loss in earnings.

Exclusive of securities where there is an intent to sell or where it is not more likely than not that the security will be required to be sold before recovery of its amortized cost basis, impairment for debt securities is separated into a credit component and a non-credit component. The credit component of an impairment is the difference between the security’s amortized cost basis and the present value of its expected future cash flows, while the non-credit component is the remaining difference between the security’s fair value and the present value of expected future cash flows. An allowance for expected credit losses will be recorded for the expected credit losses through income and the non-credit component is recognized in OCI. The amount of impairment recognized is limited to the excess of the amortized cost over the fair value of the available-for-sale debt security.

Deferred Taxes

Deferred federal income taxes arise from the recognition of temporary differences between the basis of assets and liabilities determined for financial reporting purposes and the basis determined for income tax purposes. Our temporary differences principally relate to our loss reserves, unearned and advanced premiums, DPAC, NOL and tax credit carryforwards, compensation related items, unrealized investment gains (losses) and basis differences on fixed assets, intangible assets and operating leases. Deferred tax assets and liabilities are measured using the enacted tax rates expected to be in effect when such benefits are realized. We review our deferred tax assets quarterly for impairment. If we determine that it is more likely than not that some or all of a deferred tax asset will not be realized, a valuation allowance is recorded to reduce the carrying value of the asset. In assessing the need for a valuation allowance, management is required to make certain judgments and assumptions about our future operations based on historical experience and information as of the measurement period regarding reversal of existing temporary differences, carryback capacity, future taxable income of the appropriate character (including its capital and operating characteristics) and tax planning strategies.

The largest portion of our deferred tax asset at December 31, 2024 is related to net unrealized investment losses on our fixed maturities due to the significant effect of fluctuations in interest rates beginning in 2022. Future changes in interest rates could cause significant fluctuations in the deferred tax asset. Any loss realized prior to recovery would require sufficient income of the appropriate character (i.e., capital gains), and in the appropriate time frame, to realize the tax benefit. We believe that we have the intent and ability to hold these securities until their recovery. Our projected positive operating income, including the investment income generated from holding our debt securities until maturity, support our ability to implement this tax planning strategy.

A valuation allowance has been established against the deferred tax asset related to the NOL carryforwards for our U.K. operations and against a portion of the deferred tax asset related to our U.S. state NOL carryforwards. Management concluded that it was more likely than not that this deferred tax assets will not be realized. We also established a valuation allowance in a prior year against the deferred tax assets of certain SPCs at our wholly owned Cayman Islands reinsurance subsidiary, Inova Re. Due to the cumulative losses incurred in recent years by these SPCs, management concluded that a valuation allowance was required. As of December 31, 2024, management concluded that the previously recorded valuation allowances were still required against the deferred tax assets related to the NOL carryforwards for our U.K. operations, against the deferred tax assets related to some of our U.S. state NOL carryforwards and the deferred tax assets of certain SPCs at Inova Re. Management’s assessment of the need for these valuation allowances at December 31, 2024 included an analysis of the available sources of income. See further discussion on ProAssurance’s deferred tax assets in Note 5 of the Notes to Consolidated Financial Statements.

U.S. Tax Legislation

Coronavirus Aid, Relief and Economic Security Act

In response to COVID-19, the CARES Act was signed into law on March 27, 2020 and contains several provisions for corporations and eased certain deduction limitations originally imposed by the TCJA. Temporary changes regarding NOL carryback provisions included in the CARES Act had a favorable impact on our liquidity, as we were able to carryback our 2019 and 2020 net operating losses to claim refunds (see discussion that follows in the Operating Activities and Related Cash Flows section under the heading "Taxes"). See further discussion in Note 5 of the Notes to Consolidated Financial Statements.

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Unrecognized Tax Benefits

We evaluate tax positions taken on tax returns and recognize positions in our financial statements when it is more likely than not that we will sustain the position upon resolution with a taxing authority. If recognized, the benefit is measured as the largest amount of benefit that has a greater than 50% probability of being realized. We review uncertain tax positions each quarter, considering changes in facts and circumstances, such as changes in tax law, interactions with taxing authorities and developments in case law, and make adjustments as we consider necessary. Adjustments to our unrecognized tax benefits may affect our income tax expense, and settlement of uncertain tax positions may require the use of cash. Other than differences related to timing, no significant adjustments were considered necessary during 2024 or 2023. At December 31, 2024, our liability for unrecognized tax benefits was nominal in amount.

Liquidity and Capital Resources and Financial Condition

Overview

ProAssurance Corporation is a holding company and is a legal entity separate and distinct from its subsidiaries. As a holding company, our principal source of external revenue is our investment revenues. In addition, dividends from our operating subsidiaries represent another source of funds for our obligations, including debt service and shareholder dividends, if declared. We also charge our core domestic operating subsidiaries within our Specialty P&C and Workers' Compensation Insurance segments a management fee based on the extent to which services are provided to the subsidiary and the amount of gross premium written by the subsidiary. At December 31, 2024, we held cash and liquid investments of approximately $101 million outside our insurance subsidiaries that were available for use without regulatory approval or other restriction. As of February 20, 2025, we also have an additional $125 million in permitted borrowings available under our Revolving Credit Agreement as well as the possibility of a $50 million accordion feature, if successfully subscribed, as discussed in this section under the heading "Debt."

During 2024, our operating subsidiaries paid dividends to us of $66 million. Our insurance subsidiaries, in the aggregate, are permitted to pay dividends of approximately $145 million over the course of 2025 without prior approval of state insurance regulators. However, the payment of any dividend requires prior notice to the insurance regulator in the state of domicile, and the regulator may reduce or prevent the dividend if, in its judgment, payment of the dividend would have an adverse effect on the surplus of the insurance subsidiary. We make the decision to pay dividends from an insurance subsidiary based on the capital needs of that subsidiary and may pay less than the permitted dividend or may also request permission to pay an additional amount (an extraordinary dividend).

Cash Flows

Cash flows between periods compare as follows:

Year Ended December 31
(In thousands)20242023Change
Net cash provided (used) by:
Operating activities$(10,715)$(49,885)$39,170
Investing activities10,672141,139(130,467)
Financing activities(10,974)(55,315)44,341
Increase (decrease) in cash and cash equivalents$(11,017)$35,939$(46,956)

The principal components of our operating cash flows are the excess of premiums collected and net investment income over losses paid and operating costs, including income taxes. Timing delays exist between the collection of premiums and the payment of losses associated with the premiums. Premiums are generally collected within the twelve-month period after the policy is written, while our claim payments are generally paid over a more extended period of time. Likewise, timing delays exist between the payment of claims and the collection of any associated reinsurance recoveries.

The increase in operating cash flows of $39.2 million in 2024 as compared to 2023 was primarily due to:

•A decrease in paid losses of $37.2 million driven by our Specialty P&C segment reflecting a lower number of claims resolved with large indemnity payments as compared to the prior year period. Claim costs in our MPL line of business continue to be pressured by social inflation and higher than anticipated loss severity trends.

•A decrease in cash paid for operating expenses of $28.4 million driven by a decrease in compensation-related costs, primarily as a result of a decrease in paid bonuses, premium taxes and commissions.

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•An increase in cash received from investment income of $10.7 million driven by an increase in distributed earnings and redemptions from our portfolio of investments in LPs/LLCs and higher average book yields as we took advantage of the current interest rate environment as our portfolio matures.

The increase in operating cash flows was partially offset by:

•A decrease in net premium receipts of $18.7 million primarily driven by the proactive actions we have taken in certain lines of business to improve profitability.

•The effect of a tax refund of approximately $11.7 million which we received in February 2023 (see additional discussion within this section under the heading "Taxes" that follows).

•The prior year impact of proceeds of $6.9 million received in 2023 associated with the sale of our remaining ownership interest in the underwriting and operations entity associated with Syndicate 1729 to unrelated third parties.

The remaining variance in operating cash flows in 2024 as compared to 2023 was composed of individually insignificant components.

We manage our investing cash flows to ensure that we will have sufficient liquidity to meet our obligations, taking into consideration the timing of cash flows from our investments, including interest payments, dividends and principal payments, as well as the expected cash flows to be generated by our operations as discussed in this section under the heading "Investing Activities and Related Cash Flows."

Our financing cash flows are primarily comprised of share repurchases, borrowings and repayment of debt, as well as capital contributions received from or return of capital to external SPC participants. See further discussion of share repurchases and debt in this section under the heading "Financing Activities and Related Cash Flows."

Operating Activities and Related Cash Flows

Losses

The following table, known as the Analysis of Reserve Development, presents information over the preceding ten years regarding the payment of our losses as well as changes to (the development of) our estimates of losses during that time period. As noted in the table, we have completed various acquisitions over the ten year period which have affected original and re-estimated gross and net reserve balances as well as loss payments.

The table includes losses on both a direct and an assumed basis and is net of anticipated reinsurance recoverables. The gross liability for losses before reinsurance, as shown on the balance sheet, and the reconciliation of that gross liability to amounts net of reinsurance are reflected below the table. We do not discount our reserve for losses to present value. Information presented in the table is cumulative and, accordingly, each amount includes the effects of all changes in amounts for prior years. The table presents the development of our balance sheet reserve for losses; it does not present accident year or policy year development data. Conditions and trends that have affected the development of liabilities in the past may not necessarily occur in the future. Accordingly, it is not appropriate to extrapolate future redundancies or deficiencies based on this table.

The following may be helpful in understanding the Analysis of Reserve Development:

•The line entitled “Reserve for losses, undiscounted and net of reinsurance recoverables” reflects our reserve for losses and loss adjustment expense, less the receivables from reinsurers, each as reported in our Consolidated Balance Sheets at the end of each year (the Balance Sheet Reserves).

•The section entitled “Cumulative net paid, as of” reflects the cumulative amounts paid as of the end of each succeeding year with respect to the previously recorded Balance Sheet Reserves.

•The section entitled “Re-estimated net liability as of” reflects the re-estimated amount of the liability previously recorded as Balance Sheet Reserves that includes the cumulative amounts paid and an estimate of the remaining net liability based upon claims experience as of the end of each succeeding year (the Net Re-estimated Liability).

•The line entitled “Net cumulative redundancy (deficiency)” reflects the difference between the previously recorded Balance Sheet Reserve for each applicable year and the Net Re-estimated Liability relating thereto as of the end of the most recent fiscal year.

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Analysis of Reserve Development
December 31
(In thousands)20142015201620172018201920202021202220232024
Reserve for losses, undiscounted and net of reinsurance recoverables$1,812,299$1,730,308$1,681,423$1,659,971$1,709,129$1,878,140$1,945,099$3,059,328$2,973,196$2,888,655$2,775,805
Cumulative net paid, as of:
One Year Later380,508370,973354,526387,389428,940466,904454,902756,601773,912727,893
Two Years Later640,655616,016621,783668,340734,638790,989813,7681,371,3261,342,670
Three Years Later798,636799,689800,331857,177952,3091,046,5731,101,0501,790,959
Four Years Later910,998898,844930,769990,0231,133,4621,249,1961,288,873
Five Years Later964,897974,1041,004,9511,085,2671,265,9711,373,263
Six Years Later1,006,2151,018,1481,061,4881,162,3711,337,095
Seven Years Later1,030,7821,051,4951,110,3111,198,522
Eight Years Later1,045,9801,078,6471,130,936
Nine Years Later1,066,0631,092,023
Ten Years Later1,074,763
Re-estimated net liability as of:
End of Year1,812,2991,730,3081,681,4231,659,9711,709,1291,878,1401,945,0993,059,3282,973,1962,888,655
One Year Later1,651,1171,587,0291,547,8761,565,8671,696,8931,827,1531,902,8133,015,2412,975,7932,841,623
Two Years Later1,511,5421,460,6601,444,6191,487,9051,656,6151,805,4331,885,4563,025,7862,928,757
Three Years Later1,388,6821,356,0751,337,5711,446,5711,647,2831,792,2021,890,5782,982,007
Four Years Later1,288,5641,257,6501,306,2741,432,4771,632,8361,768,4511,872,584
Five Years Later1,221,4631,231,7131,299,0321,415,0771,605,3741,746,868
Six Years Later1,204,6421,230,5621,287,7311,394,6241,593,134
Seven Years Later1,199,6541,217,7131,277,8841,384,216
Eight Years Later1,183,9731,216,7271,274,519
Nine Years Later1,186,7621,212,329
Ten Years Later1,187,289
Net cumulative redundancy (deficiency)$625,010$517,979$406,904$275,755$115,995$131,272$72,515$77,321$44,439$47,032
Original gross liability - end of year$2,052,768$1,990,266$1,961,436$1,971,303$2,037,274$2,243,133$2,295,279$3,469,417$3,373,260$3,303,558
Reinsurance recoverables(240,469)(259,958)(280,013)(311,332)(328,145)(364,993)(350,180)(410,089)(400,064)(414,903)
Original net liability - end of year$1,812,299$1,730,308$1,681,423$1,659,971$1,709,129$1,878,140$1,945,099$3,059,328$2,973,196$2,888,655
Gross re-estimated liability - latest$1,376,945$1,443,378$1,517,600$1,628,123$1,887,784$2,082,564$2,209,546$3,425,815$3,365,601$3,239,514
Re-estimated reinsurance recoverables(189,656)(231,049)(243,081)(243,907)(294,650)(335,696)(336,962)(443,808)(436,844)(397,891)
Net re-estimated liability - latest$1,187,289$1,212,329$1,274,519$1,384,216$1,593,134$1,746,868$1,872,584$2,982,007$2,928,757$2,841,623
Gross cumulative redundancy (deficiency)$675,823$546,888$443,836$343,180$149,490$160,569$85,733$43,602$7,659$64,044

See table notes on following page.

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Table Notes

•We have elected to present reserve history for acquired entities on a prospective basis in the table above; therefore, certain items will not agree to the following table which details activity in our net reserve for losses.

•Given the Lloyd's Syndicates operations are in run-off and the reserve is relatively small on a standalone basis as compared to our consolidated reserve, we have elected to exclude its reserve history for all periods presented in the table above, which is consistent with prior year; therefore, certain items will not agree to the following table which details activity in our net reserve for losses.

•Reserves for 2014 include gross and net reserves acquired in 2014 business combinations of $153.2 million and $139.5 million, respectively.

•Reserves for 2021 include gross and net reserves acquired in 2021 business combinations of $1.2 billion and $1.1 billion, respectively.

In each year reflected in the table, we have estimated our reserve for losses utilizing the management and actuarial processes discussed under the heading "Reserve for Losses and Loss Adjustment Expenses" in the Critical Accounting Estimates section. Factors that have contributed to the variation in loss development are primarily related to the extended period of time required to resolve professional liability claims and include the following:

•The MPL legal environment deteriorated in the late 1990’s and severity began to increase at a greater pace than anticipated in our rates and reserve estimates. We addressed the adverse severity trends through increased rates, stricter underwriting and modifications to claims handling procedures, and reflected this adverse severity trend when we established our initial reserves for subsequent years.

•These adverse severity trends later moderated, with that moderation becoming more pronounced beginning in 2009. We were cautious in giving full recognition to indications that the pace of severity increase had slowed, however we gave measured recognition of the improved trend in our reserve estimates. The favorable development was most pronounced for years 2004 to 2008, as the initial reserves for these accident years were established prior to substantial indication that severity trends were moderating. We gave stronger recognition to the lower severity trend as time elapsed and a greater percentage of claims were closed.

•A general decline in claims frequency has also been a contributor to favorable loss development. A significant portion of our policies through 2003 were issued on an occurrence basis, and a smaller portion of our ongoing business results from the issuance of extended reporting endorsements which have occurrence-like exposure. As claims frequency declined, the number of reported claims related to these coverages was less than originally expected.

•Beginning in 2017, we identified potential higher severity trends in the broader MPL industry. These trends were also reflected in increases in estimates of ultimate losses for open MPL claims for earlier accident years, which resulted in a lower amount of favorable development recognized in 2018 and 2017 as compared to prior years.

•During 2019 the loss experience in our Specialty book in our Specialty P&C segment deteriorated further, particularly in regard to the reserves we established for a large national healthcare account that experienced losses far exceeding the assumptions we made when underwriting the account, beginning in 2016. As a result, we strengthened our Specialty reserves through the recognition of net unfavorable development on prior accident years and a higher current accident year net loss ratio in our Specialty P&C segment in 2019.

•The loss environment in our MPL line of business in our Specialty P&C segment continues to be challenging in many jurisdictions, as claim costs are pressured by social inflation and higher than anticipated loss severity trends which started to emerge in the fourth quarter of 2022. We continue to monitor the impact that these trends have on our open case reserves and prior accident year development. Further, beginning in the second half of 2023, we observed higher than expected loss trends in our average cost per claim in our Workers' Compensation Insurance segment which we primarily attribute to increased medical costs driven by wage inflation and medical advancements. In response to these trends, we increased both our current accident year loss ratio and prior year reserves in our Workers' Compensation Insurance segment in 2023.

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Activity in our net reserve for losses during 2024, 2023 and 2022 is summarized below:

Year Ended December 31
(In thousands)202420232022
Balance, beginning of year$3,401,281$3,471,147$3,579,940
Less reinsurance recoverables on unpaid losses and loss adjustment expenses445,573431,889451,741
Net balance, beginning of year2,955,7083,039,2583,128,199
Net losses:
Current year(1)779,650794,848813,515
(Favorable) unfavorable development of reserves established in prior years, net(1)(40,215)5,646(36,753)
Total739,435800,494776,762
Paid related to:
Current year(113,268)(101,996)(108,139)
Prior years(733,248)(782,048)(757,564)
Total paid(846,516)(884,044)(865,703)
Net balance, end of year2,848,6272,955,7083,039,258
Plus reinsurance recoverables on unpaid losses and loss adjustment expenses409,069445,573431,889
Balance, end of year$3,257,696$3,401,281$3,471,147

(1) Current year net losses for the year ended December 31, 2022 and net prior year reserve development recognized for years ended December 31, 2024, 2023 and 2022 includes certain purchase accounting adjustments associated with our acquisition of NORCAL. See Note 7 of the Notes to Consolidated Financial Statements for additional information.

At December 31, 2024 our gross reserve for losses included case reserves of approximately $2.1 billion and IBNR reserves of approximately $1.2 billion. Our consolidated gross reserve for losses on a GAAP basis exceeds the combined gross reserves of our insurance subsidiaries on a statutory basis by approximately $215 million, which is principally due to the portion of the GAAP reserve for losses that is reflected for statutory accounting purposes as unearned premiums. These unearned premiums are applicable to extended reporting endorsements (“tail” coverage) issued without a premium charge upon death, disability or retirement of an insured who meets certain qualifications.

Reinsurance

Within our Specialty P&C segment, we use insurance and reinsurance (collectively, “reinsurance”) to provide capacity to write larger limits of liability, to provide reimbursement for losses incurred under the higher limit coverages we offer and to provide protection against losses in excess of policy limits. Within our Workers' Compensation Insurance segment, we use reinsurance to reduce our net liability on individual risks, to mitigate the effect of significant loss occurrences (including catastrophic events), to stabilize underwriting results and to increase underwriting capacity by decreasing leverage. In both our Specialty P&C and Workers' Compensation Insurance segments, we use reinsurance in risk sharing arrangements to align our objectives with those of our strategic business partners and to provide custom insurance solutions for large customer groups. The purchase of reinsurance does not relieve us from the ultimate risk on our policies; however, it does provide reimbursement for certain losses we pay. We pay our reinsurers a premium in exchange for reinsurance of the risk. In certain of our excess of loss arrangements, the premium due to the reinsurer is determined by the loss experience of the business reinsured, subject to certain minimum and maximum amounts. Until all loss amounts are known, we estimate the premium due to the reinsurer. Changes to the estimate of premium owed under reinsurance agreements related to prior periods are recorded in the period in which the change in estimate occurs and can have a significant effect on net premiums earned.

We offer alternative market solutions whereby we cede certain premiums from our Workers' Compensation Insurance and Specialty P&C segments to either the SPCs at Inova Re, one of our Cayman Islands reinsurance subsidiaries which is reported in our Segregated Portfolio Cell Reinsurance segment, or captive insurers unaffiliated with ProAssurance for two programs. The majority of these policies are reinsured to the SPCs at Inova Re, net of a ceding commission. See further discussion on our SPC operations in the Segment Results - Segregated Portfolio Cell Reinsurance section that follows. The alternative market workers' compensation policies are ceded from our Workers' Compensation Insurance segment to the SPCs under 100% quota share reinsurance agreements. The alternative market medical professional liability policies are ceded from our Specialty P&C segment to the SPCs under either excess of loss or quota share reinsurance agreements, depending on the structure of the

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individual program. The portion of the risk that is not ceded to an SPC is retained in our Specialty P&C segment and may also be reinsured under our standard medical professional liability reinsurance program, depending on the policy limits provided. The remaining premium written in our alternative market business is 100% ceded to unaffiliated captive insurers.

Excess of Loss Reinsurance Agreements

We generally reinsure risks under treaties (our excess of loss reinsurance agreements) pursuant to which the reinsurers agree to assume all or a portion of all risks that we insure above our individual risk retention levels, up to the maximum individual limits offered. These agreements are negotiated and renewed annually. Our Medical Professional Liability and Medical Technology Liability treaties renew annually on October 1 and our workers' compensation treaty renews annually on May 1. Our MPL and Medical Technology Liability treaties renewed October 1, 2024. Our MPL treaty renewal incorporated podiatric and chiropractic policies and MPL coverages in excess of $2 million changed from 9% to 0% co-participation. The next $24 million of risk changed from 9.5% to 7.5% co-participation. Our Medical Technology Liability treaty renewed at a higher rate than the previous treaty. All other material terms were consistent with the expiring treaties. Our traditional workers' compensation treaty renewed May 1, 2024 at a higher contract rate than the previous treaty and included the elimination of the AAD as well as an increase in the per occurrence retention to $0.75 million from $0.5 million. Overall, the impact of our traditional workers' compensation treaty renewal is expected to increase our ceded premium ratio while losses related to the increase in the per occurrence retention are expected to be more than offset by the elimination of the AAD. The significant coverages provided by our current excess of loss reinsurance agreements are depicted in the following table.

Current Excess of Loss Reinsurance Agreements

Column 1Column 2Column 3Column 4Column 5Column 6
MedicalProfessional LiabilityMedical Technology & Life Sciences ProductsWorkers' Compensation - Traditional

(1) Effective October 1, 2020, one prepaid limit reinstatement of $21M and a second limit reinstatement of up to $21M for the second layer, subject to reinstatement premium, which attaches after the first reinstatement has been completely exhausted. All limit reinstatements thereafter require no additional premium. Effective October 1, 2021, limits can be reinstated a maximum of four times.

(2) Prior to October 1, 2020, retention was $1M.

(3) Historically, retention has ranged from 0% to 32.5%.

(4) Historically, retention has ranged from $1M to $2M.

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(5) Subject to a limit of $20M per individual claimant. If an individual loss were to exceed this level the Company would retain this excess exposure. Historically, the limit per individual claimant has ranged from $15M to $20M.

(6) Historically, retention has ranged from $0.5M to $0.75M.

Large MPL risks that are above the limits of our basic reinsurance treaties may be reinsured on a facultative basis, whereby the reinsurer agrees to insure a particular risk up to a designated limit. We also have in place a number of risk sharing arrangements that apply to the first $1 million of losses for certain large healthcare systems and other insurance entities.

Other Reinsurance Arrangements

For the workers' compensation business ceded to Inova Re; each SPC has in place its own reinsurance arrangements, which are illustrated in the following table.

Segregated Portfolio Cell Reinsurance

Column 1Column 2Column 3
Per Occurrence CoverageAggregate Coverage

(1) The attachment point is based on a percentage of written premium within individual cells, ranges from 85% to 94%, and varies by cell.

Each SPC has participants and the profit or loss of each cell accrues fully to these cell participants. As previously discussed, we participate in certain SPCs to a varying degree. Each SPC maintains a loss fund initially equal to the difference between premium assumed by the cell and the ceding commission. The external participants of each cell provide collateral to us, typically in the form of a letter of credit that is initially equal to the difference between the loss fund of the SPC (amount of funds available to pay losses after deduction of ceding commission) and the aggregate attachment point of the reinsurance. Over time, an SPC's retained profits are considered in the determination of the collateral amount required to be provided by the cell's external participants.

Taxes

We are subject to the tax laws and regulations of the U.S., Cayman Islands and U.K. We file a consolidated U.S. federal income tax return that includes the parent company and its U.S. subsidiaries, except for ProAssurance American Mutual, A Risk Retention Group. Our filing obligations include a requirement to make quarterly payments of estimated taxes to the IRS using the corporate tax rate effective for the tax year. We did not make any quarterly estimated tax payments during the year ended December 31, 2024; however, estimated taxable income after consideration of NOL carryforwards and previously

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deferred tax credits from our tax credit partnership investments as of December 31, 2024, indicates that an extension payment will be necessary in early 2025.

As a result of the CARES Act that was signed into law on March 27, 2020 we were permitted to carryback NOLs generated in tax years 2019 and 2020 for up to five years. We generated an NOL of approximately $33.3 million from the 2020 tax year that was carried back to the 2015 tax year that resulted in a tax refund of approximately $11.7 million which was received in February 2023. In addition, the CARES Act included the initial version of the ERC which was extended and expanded in December 2020 and March 2021. See further discussion of the ERC in Note 1 of the Notes to Consolidated Financial Statements. As an eligible employer under the provisions of the CARES Act, NORCAL filed a claim for a payroll tax refund of approximately $3.8 million during the second quarter of 2023, based on eligible wages paid during 2020.

As a result of the NORCAL acquisition, we have U.S. federal NOL carryforwards, which were approximately $18.9 million as of December 31, 2024. These NOL carryforwards are subject to limitation by Internal Revenue Code Section 382 and will begin to expire in 2035.

Investing Activities and Related Cash Flows

Our investments at December 31, 2024 and December 31, 2023 are comprised as follows:

December 31, 2024December 31, 2023
($ in thousands)Carrying Value% of Total InvestmentCarrying Value% of Total Investment
Fixed maturities, available-for-sale:
U.S. Treasury obligations$243,9035%$243,5255%
U.S. Government-sponsored enterprise obligations14,8941%18,7241%
State and municipal bonds446,60110%454,38110%
Corporate debt1,727,77540%1,750,57440%
Residential mortgage-backed securities478,79911%430,13710%
Commercial mortgage-backed securities208,5135%197,8615%
Other asset-backed securities461,72210%398,3959%
Total fixed maturities, available-for-sale3,582,20782%3,493,59780%
Fixed maturities, trading53,1571%48,3241%
Total fixed maturities3,635,36483%3,541,92181%
Equity investments(1)130,1583%151,2954%
Short-term investments254,9225%235,7855%
BOLI80,1792%78,2052%
Investment in unconsolidated subsidiaries259,5386%276,7566%
Other investments7,2661%65,8192%
Total investments$4,367,427100%$4,349,781100%
(1)Includes $101.2 million and $114.9 million of investment grade bond funds as of December 31, 2024 and 2023, respectively, which are not subject to significant equity price risk.

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At December 31, 2024, 99% of our investments in available-for-sale fixed maturity securities were rated and the average rating was A+. The distribution of our investments in available-for-sale fixed maturity securities by rating were as follows:

December 31, 2024December 31, 2023
($ in thousands)Carrying Value% of Total InvestmentCarrying Value% of Total Investment
Rating*
AAA$571,13916%$489,12114%
AA+710,84120%689,49120%
AA208,9866%206,4716%
AA-174,3495%180,8275%
A+248,3537%286,7238%
A413,25911%410,93512%
A-381,74611%374,61211%
BBB+197,1425%194,1405%
BBB297,2668%286,3788%
BBB-138,6934%138,3994%
Below investment grade239,5776%233,4056%
Not rated8561%3,0951%
Total$3,582,207100%$3,493,597100%
*Average of three NRSRO sources, presented as an S&P equivalent. Source: S&P, Copyright ©2025, S&P Global Market Intelligence

A detailed listing of our investment holdings as of December 31, 2024 is located under the Financial Information heading on the Investor Relations page of our website which can be reached directly at https://investor.proassurance.com/financial-information/quarterly-investment-supplements/default.aspx or through links from the Investor Relations section of our website, https://investor.proassurance.com/corporate-profile/default.aspx.

We manage our investments to ensure that we will have sufficient liquidity to meet our obligations, taking into consideration the timing of cash flows from our investments, including interest payments, dividends and principal payments, as well as the expected cash flows to be generated or used by our operations. In addition to the interest and dividends we will receive from our investments, we anticipate that between $100 million and $140 million of our portfolio will mature (or be paid down) each quarter over the next twelve months and become available, if needed, to meet our cash flow requirements. Our reinvestment rate of cash flows compared to recent years is more intermittent due to anticipated higher severity and paid loss trends in our MPL line of business and our Workers' Compensation Insurance segment. From time to time our cash balances will fluctuate depending on the actual timing of paid losses. The primary outflow of cash at our insurance subsidiaries is related to paid losses and operating costs, including income taxes. The payment of individual claims cannot be predicted with certainty; therefore, we rely upon the history of paid claims in estimating the timing of future claims payments with consideration given to current and anticipated industry trends and macroeconomic conditions. To the extent that we may have an unanticipated shortfall in cash, we may either liquidate securities or borrow funds under existing borrowing arrangements through our Revolving Credit Agreement and the FHLB system. As of February 20, 2025, $175 million could be made available for use through our Revolving Credit Agreement, as discussed in this section under the heading "Debt." Given the duration of our investments, we do not foresee a shortfall that would require us to meet operating cash needs through additional borrowings. Additional information regarding our Revolving Credit Agreement is detailed in Note 10 of the Notes to Consolidated Financial Statements.

At December 31, 2024, our FAL was comprised of cash and cash equivalents and investment securities, primarily available-for-sale fixed maturities, deposited with Lloyd's which had a fair value of $11.7 million. During 2024, we received a return of approximately $9.1 million of cash from our FAL balances due to lower capital requirements for the 2023 underwriting year and lower economic capital assessments. Additional information regarding our FAL is detailed in Note 3 of the Notes to Consolidated Financial Statements.

Our investment portfolio continues to be primarily composed of high quality fixed income securities with approximately 93% of our fixed maturities being investment grade securities as determined by national rating agencies. The weighted average effective duration of our fixed maturity securities at December 31, 2024 was 3.22 years; the weighted average effective duration of our fixed maturity securities combined with our short-term securities was 3.01 years.

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The carrying value and unfunded commitments for certain of our investments were as follows:

Carrying ValueDecember 31, 2024
($ in thousands, except expected funding period)December 31, 2024December 31, 2023Unfunded CommitmentExpected funding period in years
Qualified affordable housing project tax credit partnerships (1)$247$666$672
All other investments, primarily investment fund LPs/LLCs259,291276,090148,6574
Total$259,538$276,756$148,724
(1) The carrying value reflects our total commitments (both funded and unfunded) to the partnerships, less any amortization, since our initial investment. We fund these investments based on funding schedules maintained by the partnerships.

Investment fund LPs/LLCs are by nature less liquid and may involve more risk than other investments. We manage our risk through diversification of asset class and geographic location. At December 31, 2024, we had investments in 35 separate investment funds with a total carrying value of $259.3 million which represented approximately 6% of our total investments. Our investment fund LPs/LLCs generate earnings from trading portfolios, secured debt, debt securities, multi-strategy funds and private equity investments, and the performance of these LPs/LLCs is affected by the volatility of equity and credit markets. For our investments in LPs/LLCs, we record our allocable portion of the partnership operating income or loss as the results of the LPs/LLCs become available, typically following the end of a reporting period. As of December 31, 2024, our total funding commitments legally outstanding related to our investments in LPs/LLCs were approximately $148.7 million; however, we anticipate capital of approximately $82 million to be drawn based on our current estimates.

Financing Activities and Related Cash Flows

Treasury Shares

Treasury share activity for 2024, 2023 and 2022 was as follows:

(Share amounts in thousands)202420232022
Treasury shares at the beginning of the period12,6079,4649,325
Shares reacquired, at cost of $50.5 million and $3.3 million for 2023 and 2022, respectively3,143139
Treasury shares at the end of the period12,60712,6079,464

We did not repurchase any common shares subsequent to December 31, 2024, and as of February 20, 2025, our remaining Board authorization was approximately $55.9 million.

Debt

Our outstanding debt consisted of the following:

($ in thousands)December 31, 2024December 31, 2023
Contribution Certificates$181,163$179,387
Revolving Credit Agreement125,000125,000
Term Loan120,313125,000
Total principal426,476429,387
Less unamortized debt issuance costs1,6032,254
Debt less unamortized debt issuance costs$424,873$427,133

Additional information regarding our debt is provided in Note 10 of the Notes to Consolidated Financial Statements.

To manage our exposure to interest rate risk due to variability in the base rate on borrowings under the Revolving Credit Agreement and Term Loan, we entered into two forward-starting interest rate swap agreements ("Interest Rate Swaps"). Additional information regarding our Interest Rate Swaps is provided in Note 11 of the Notes to Consolidated Financial Statements.

Two of our insurance subsidiaries are members of an FHLB. Through membership, those subsidiaries have access to secured cash advances which can be used for liquidity purposes or other operational needs. In order for us to use FHLB

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proceeds, regulatory approvals may be required depending on the nature of the transaction. To date, those subsidiaries have not materially utilized their membership for borrowing purposes.

Contingent Consideration

During 2024, the contingent consideration associated with the 2021 NORCAL acquisition was settled, and the corresponding liability was reduced to zero as of June 30, 2024. The $6.5 million decrease during the year ended December 31, 2024 was recognized as a component of net investment gains (losses). During the year ended December 31, 2023, we recorded an $8.5 million decrease to the contingent consideration liability comprised of $5.0 million related to the remeasurement of the liability to fair value (component of net investment gains (losses)) and $3.5 million related to the impact of unfavorable development recognized in 2023 on NORCAL's reserves related to accident years 2020 and prior (component of operating expenses). See further discussion that follows under the heading "Results of Operations."

Contingent consideration is measured at fair value on the date of acquisition and remeasured at fair value each subsequent reporting period. Fair value of a liability represents the price that would be paid to transfer the liability in an orderly transaction between market participants at the measurement date considering characteristics specific to the liability. As of December 31, 2023, the contingent consideration liability was $6.5 million carried at fair value utilizing a stochastic model (see Note 2 of the Notes to Consolidated Financial Statements). As of December 31, 2023, the remaining uncertainty around the analysis to be performed by the independent actuary was a significant component in the determination of the fair value of the liability. See further discussion around the contingent consideration in Note 1, Note 2 and Note 8 of the Notes to Consolidated Financial Statements.

Given the contingent consideration associated with the NORCAL acquisition was dependent upon the after-tax development of NORCAL's ultimate net losses between December 31, 2020 and December 31, 2023, we bifurcated changes in the contingent consideration for periods prior to 2024 between fair value changes and, if applicable, changes in estimates of NORCAL's ultimate net losses for accident years 2020 and prior. See further discussion regarding our estimates of ultimate net losses under the heading "Reserve for Losses and Loss Adjustment Expenses" in the Critical Accounting Estimates section. Changes in the contingent consideration related to fair value are recognized in earnings as a component of net investment gains (losses) and changes in the contingent consideration related to changes in estimates of NORCAL's ultimate net losses for accident years 2020 and prior are recognized in earnings as a component of operating expenses.

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Results of Operations - Year Ended December 31, 2024 Compared to Year Ended December 31, 2023

Selected consolidated financial data for each period is summarized in the table below.

Year Ended December 31
($ in thousands, except per share data)20242023Change
Revenues:
Net premiums written$953,675$985,994$(32,319)
Net premiums earned$968,250$977,397$(9,147)
Net investment result166,741135,21031,531
Net investment gains (losses)1,90313,828(11,925)
Other income (expense)13,51010,7772,733
Total revenues1,150,4041,137,21213,192
Expenses:
Net losses and loss adjustment expenses739,435800,494(61,059)
Underwriting, policy acquisition and operating expenses319,339300,74418,595
SPC U.S. federal income tax expense (benefit)1,7661,629137
SPC dividend expense (income)4,4446,234(1,790)
Interest expense22,34223,150(808)
Goodwill impairment44,110(44,110)
Total expenses1,087,3261,176,361(89,035)
Income (loss) before income taxes63,078(39,149)102,227
Income tax expense (benefit)10,334(545)10,879
Net income (loss)$52,744$(38,604)$91,348
Non-GAAP operating income (loss)$48,592$(9,014)$57,606
Earnings (loss) per share:
Basic$1.03$(0.73)$1.76
Diluted$1.03$(0.73)$1.76
Non-GAAP operating income (loss) per share:
Basic$0.95$(0.17)$1.12
Diluted$0.95$(0.17)$1.12
Net loss ratio76.4%81.9%(5.5 pts)
Underwriting expense ratio33.0%30.8%2.2 pts
Combined ratio109.4%112.7%(3.3 pts)
Operating ratio94.5%99.6%(5.1 pts)
Effective tax rate16.4%1.4%15.0 pts
Return on equity*4.6%(3.5%)8.1 pts
Non-GAAP operating return on equity*4.2%(0.8%)5.0 pts
*See further discussion on this calculation in the Executive Summary of Operations section under the heading "Non-GAAP Operating ROE."
In all tables that follow, the abbreviation "nm" indicates that the information or the percentage change is not meaningful.

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Executive Summary of Operations

The following sections provide an overview of our consolidated and segment results of operations for the year ended December 31, 2024 as compared to the year ended December 31, 2023. See the Segment Results sections that follow for additional information regarding each segment's results. For a full discussion of the changes in the financial condition, results of operations and cash flows for the year ended December 31, 2023 as compared to the year ended December 31, 2022, please refer to Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" section of ProAssurance's December 31, 2023 report on Form 10-K.

Revenues

The following table shows our consolidated and segment net premiums earned:

Year Ended December 31
($ in thousands)20242023Change
Net premiums earned
Specialty P&C$747,942$755,817$(7,875)(1.0%)
Workers' Compensation Insurance167,610160,0347,5764.7%
Segregated Portfolio Cell Reinsurance52,69861,546(8,848)(14.4%)
Consolidated total$968,250$977,397$(9,147)(0.9%)

For the year ended December 31, 2024, consolidated net premiums decreased $9.1 million as compared to 2023.

•For our Specialty P&C segment, net premiums earned decreased during 2024 as compared to 2023 driven by our ceased participation in Syndicate 1729 for the 2024 underwriting year and, to a lesser extent, the pro rata effect of a decrease in the volume of premium written during the preceding twelve months, primarily due to proactive actions taken in certain lines to improve profitability.

•For our Workers' Compensation Insurance segment, net premiums earned increased in 2024 due to higher renewal premium, including the renewal of certain policies as traditional business that were previously written in one of the alternative market programs in our Segregated Portfolio Cell Reinsurance segment, and an increase in audit premium billed to policyholders, partially offset by the continuation of competitive market conditions.

•Net premiums earned in our Segregated Portfolio Cell Reinsurance segment decreased during 2024 primarily due to the non-renewal of two programs; however, as the underlying policies expired in one of these programs, a majority of those policies renewed as traditional business in our Workers' Compensation Insurance segment. The other program, in which we do not participate in the underwriting results, assumed both workers' compensation insurance and medical professional liability insurance.

The following table shows our consolidated net investment result:

Year Ended December 31
($ in thousands)20242023Change
Net investment income$144,538$128,419$16,11912.6%
Equity in earnings (loss) of unconsolidated subsidiaries*22,2036,79115,412226.9%
Net investment result$166,741$135,210$31,53123.3%
*Equity in earnings (loss) of unconsolidated subsidiaries includes our share of the operating results of interests we hold in certain LPs/LLCs as well as the operating results associated with our tax credit partnership investments, which are designed to generate returns in the form of tax credits and tax-deductible project operating losses. See further discussion around our tax credit partnership investments in the Segment Results - Corporate section under the heading "Net Investment Income" that follows.

The increase in our consolidated net investment income for the year ended December 31, 2024 as compared to 2023 reflected higher average book yields as we took advantage of the current interest rate environment as well as an increase in average investment balances. Our equity in earnings of unconsolidated subsidiaries increased in 2024 as compared to 2023 driven by the performance of certain LPs/LLCs. These results are typically reported on a one-quarter lag, and the increase reflected higher market valuations during the fourth quarter of 2023 and first half of 2024.

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The following table shows our total consolidated net investment gains (losses):

Year Ended December 31
($ in thousands)20242023Change
Net impairment losses recognized in earnings$(3,196)$(3,111)$(85)2.7%
Contingent Consideration remeasurement gain(1)6,5005,0001,50030.0%
Other net investment gains (losses)(1,401)11,939(13,340)(111.7%)
Net investment gains (losses)$1,903$13,828$(11,925)(86.2%)
(1) Represents the change in the fair value of contingent consideration issued in connection with the NORCAL acquisition. See previous discussion under the heading "Contingent Consideration" in the Financing Activities and Related Cash Flows section. We do not consider these adjustments in assessing the financial performance of any of our segments and therefore, we have excluded them from the Segment Results sections that follow. See Note 16 of the Notes to Consolidated Financial Statements for a reconciliation of our segment results to our consolidated results.

For the year ended December 31, 2024, we recognized $3.3 million of credit-related impairment losses in earnings, primarily related to four corporate bonds in the real estate sector. For the year ended December 31, 2023, we recognized credit-related impairment losses in earnings of $3.1 million related to a mortgage-backed security and two corporate bonds in the financial sector. Additional information regarding investment impairment losses is provided in Note 3 of the Notes to Consolidated Financial Statements.

We recognized $1.4 million of other net investment losses for the year ended December 31, 2024 driven by net realized losses from the sale of certain available-for-sale fixed maturities and, to a lesser extent, unrealized holding losses resulting from changes in the fair value of our equity investments. We recognized $11.9 million of other net investment gains for the year ended December 31, 2023 driven by unrealized holding gains resulting from changes in the fair value of our convertible securities and equity investments and, to a lesser extent, death benefit proceeds from BOLI contracts.

Consolidated other income (expense) for the year ended December 31, 2024 as compared to 2023 was comprised as follows:

Year Ended December 31
($ in thousands)20242023Change
Foreign currency exchange rate gains (losses)(1)$6,731$(2,993)$9,724324.9%
Other6,77913,770(6,991)(50.8%)
Other income (expense)$13,510$10,777$2,73325.4%
(1) Includes a gain of $0.3 million for the year ended December 31, 2024 related to a foreign currency forward contract, which is designed to mitigate our exposure related to fluctuations in exchange rates associated with foreign currency denominated available-for-sale fixed maturities and loss reserves. Additional information regarding our foreign currency forward contract is provided in Note 11 of the Notes to the Consolidated Financial Statements.

Excluding foreign currency exchange movements, other income decreased for the year ended December 31, 2024 as compared to 2023 driven by proceeds of $6.9 million received in 2023 associated with the sale of our remaining ownership interest in the underwriting and operations entity associated with Syndicate 1729 to unrelated third parties.

Foreign currency exchange rate movements are primarily related to foreign currency denominated loss reserves associated with premium assumed from an international medical professional liability insured in our Specialty P&C segment. Our participation in this program has grown in recent years which has led to greater volatility in our results of operations even with nominal movements in exchange rates given the size of the reserve. We mitigate foreign exchange exposure by generally matching the currency and duration of associated investments to the corresponding loss reserves as well as utilizing foreign currency forward contracts. When we invest in foreign currency denominated available-for-sale fixed maturities, in accordance with GAAP, the change in market value due to changes in foreign currency exchange rates is reflected as part of OCI. Conversely, the impact of changes in foreign currency exchange rates on loss reserves is reflected through net income (loss) as a component of other income (expense). The effect of exchange rate movements on foreign currency denominated loss reserves are reported in our Corporate segment to be consistent with the reporting of the foreign currency denominated invested assets and associated investment income.

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Expenses

The following table shows our consolidated and segment net loss ratios and net prior accident year reserve development.

Year Ended December 31
($ in millions)20242023Change
Current accident year net loss ratio
Consolidated ratio80.5%81.3%(0.8pts)
Specialty P&C82.3%82.6%(0.3pts)
Workers' Compensation Insurance77.0%81.3%(4.3pts)
Segregated Portfolio Cell Reinsurance66.8%65.5%1.3pts
Calendar year net loss ratio
Consolidated ratio76.4%81.9%(5.5pts)
Specialty P&C77.3%82.7%(5.4pts)
Workers' Compensation Insurance76.7%87.1%(10.4pts)
Segregated Portfolio Cell Reinsurance61.6%59.1%2.5pts
Favorable (unfavorable) reserve development, prior accident years
Consolidated$40.2$(5.6)$45.8
Specialty P&C$36.9$(0.3)$37.2
Workers' Compensation Insurance$0.5$(9.3)$9.8
Segregated Portfolio Cell Reinsurance$2.8$4.0$(1.2)

Each line of business' contribution to the change in our consolidated current accident year net loss ratio for the year ended December 31, 2024 as compared to 2023 is as follows:

(In percentage points)Increase (Decrease)2024 versus 2023
Estimated ratio increase (decrease) attributable to:
Medical Professional Liability (1)(0.5 pts)
Medical Technology Liability0.1 pts
Workers' Compensation Insurance (2)(0.7 pts)
Segregated Portfolio Cell Reinsurance0.1 pts
Other0.2 pts
Decrease in the consolidated current accident year net loss ratio(0.8 pts)

(1) The improvement in the MPL line of business current accident year net loss ratio, which represents the largest product line within our Specialty P&C segment, was driven by our continued underwriting and pricing actions which have resulted in our decrease to certain expected loss ratios during the first quarter of 2024.

(2) The improvement in the Workers' Compensation Insurance segment's current accident year net loss ratio reflects the impact of underwriting actions taken in 2023 due to higher than expected average claim costs that we began to observe and react to in 2023. While we continue to observe, and therefore reflect, higher medical loss cost trends, we have seen these trends begin to moderate in 2024, including a reduction in the 2024 average cost per claim.

Our consolidated calendar year net loss ratio can be lower than or higher than our consolidated current accident year net loss ratio due to the recognition of either favorable or unfavorable prior accident year reserve development, respectively. For all periods presented, total net prior accident year reserve development included the favorable impacts of purchase accounting amortization, as shown in the following table.

Year Ended December 31
($ in thousands)20242023Change
Net favorable (unfavorable) reserve development$34,891$(13,978)$48,869349.6%
NORCAL Acquisition - Purchase Accounting Amortization5,3248,332(3,008)(36.1%)
Total net favorable (unfavorable) reserve development$40,215$(5,646)$45,861812.3%

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Net favorable reserve development recognized in 2024 is primarily attributable to favorable trends in claim closing patterns in our MPL line of business in our Specialty P&C segment. See the Segment Results sections that follow for additional information regarding each segment's current accident year net loss ratio and net prior accident year reserve development.

Our consolidated and segment underwriting expense ratios were as follows:

Year Ended December 31
20242023Change
Underwriting Expense Ratio
Consolidated (1)33.0%30.8%2.2pts
Specialty P&C27.2%25.8%1.4pts
Workers' Compensation Insurance37.0%34.4%2.6pts
Segregated Portfolio Cell Reinsurance34.3%33.2%1.1pts
Corporate (2)4.1%3.5%0.6pts
(1) Consolidated underwriting expenses for 2024 include $0.3 million of actuarial consulting fees paid in connection with the final determination of contingent consideration associated with the acquisition of NORCAL. These transaction-related costs are not included in a segment as we do not consider these costs in assessing the financial performance of any of our operating or reportable segments. We did not incur any transaction-related costs during 2023. See Note 16 of the Notes to Consolidated Financial Statements for a reconciliation of our segment results to our consolidated results.
(2) There are no net premiums earned associated with the Corporate segment. Ratios shown are the contribution of the Corporate segment to the consolidated ratio (Corporate operating expenses divided by consolidated net premiums earned).

The change in our consolidated underwriting expense ratio for the year ended December 31, 2024 as compared to 2023 was primarily attributable to the following:

(In percentage points)Increase (Decrease) 2024 versus 2023
Estimated ratio increase (decrease) attributable to:
Change in Net Premiums Earned and DPAC amortization0.2 pts
Prior Year One-Time Items0.7 pts
All other, net1.3 pts
Increase in the underwriting expense ratio2.2 pts

•Excluding the impact of the items specifically identified in the table above, our consolidated underwriting expense ratio increased by 1.3 percentage points in 2024 as compared to 2023 driven by higher amounts accrued for performance-related incentive plans across the organization due to the improvement in the related performance metrics, partially offset by a decrease in professional fees.

•As shown in the previous table, our consolidated underwriting expense ratio for 2024 reflected the impact of the change in DPAC amortization which was relatively in line with the corresponding change in net premiums earned as compared to 2023.

•As shown in the previous table, our consolidated underwriting expense ratio for 2024 reflected the prior year impact of certain one-time items that are unique or non-recurring in nature recorded in 2023 that resulted in a benefit to operating expenses in our Specialty P&C segment. We recognized a claim for a payroll tax refund of $3.8 million related to the employee retention credit and a reduction to operating expenses of $3.5 million related to the reduction to the contingent consideration liability associated with the NORCAL acquisition. See additional discussion on the ERC in Note 1 of the Notes to Consolidated Financial Statements and previous discussion on contingent consideration in the Financing Activities and Related Cash Flows section under the heading "Contingent Consideration."

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Taxes

Our consolidated effective tax rates for the years ended December 31, 2024 and 2023 were as follows:

($ in thousands)Year Ended December 31
20242023Change
Income (loss) before income taxes$63,078$(39,149)$102,227261.1%
Income tax expense (benefit)10,334(545)10,8791,996.1%
Net income (loss)$52,744$(38,604)$91,348236.6%
Effective tax rate16.4%1.4%15.0 pts

The comparability of our effective tax rates is impacted by the consolidated pre-tax income recognized during 2024 as compared to the consolidated pre-tax loss recognized during 2023. See further discussion on our effective tax rate in the Segment Results - Corporate section that follows under the heading "Taxes."

Operating Ratio

Our operating ratio is our combined ratio, less our investment income ratio. This ratio provides the combined effect of underwriting profitability and investment income. Our operating ratio for the years ended December 31, 2024 and 2023 was as follows:

Year Ended December 31
20242023Change
Combined ratio109.4%112.7%(3.3pts)
Less: investment income ratio14.9%13.1%1.8pts
Operating ratio94.5%99.6%(5.1pts)

The primary drivers of the change in our operating ratio were as follows:

(In percentage points)Increase (Decrease) 2024 versus 2023
Estimated ratio increase (decrease) attributable to:
Change in Prior Accident Year Reserve Development(1)(4.7 pts)
Investment Income(1.8 pts)
Prior Year One-Time Items0.7 pts
All other, net0.7 pts
Decrease in the operating ratio(5.1 pts)
(1) Includes the impact of purchase accounting amortization on prior accident year reserve development related to the NORCAL acquisition.

Excluding the impact of the items specifically identified in the table above, our operating ratio in 2024 increased by approximately 0.7 percentage points as compared to 2023 driven by an increase in the consolidated underwriting expense ratio, partially offset by an improvement in the current accident year net loss ratio in our Workers' Compensation Insurance and Specialty P&C segments. See previous discussion in this section under the heading "Expenses" and further discussion in our Segment Results sections that follow.

Non-GAAP Financial Measures

Non-GAAP Operating Income (Loss)

Non-GAAP operating income (loss) is a financial measure that is widely used to evaluate performance within the insurance sector. In calculating Non-GAAP operating income (loss), we have excluded the effects of the items listed in the following table that do not reflect normal results. We believe Non-GAAP operating income (loss) presents a useful view of the

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performance of our ongoing core insurance operations; however, it should be considered in conjunction with net income (loss) computed in accordance with GAAP.

The following table is a reconciliation of net income (loss) to Non-GAAP operating income (loss):

Year Ended December 31
(In thousands, except per share data)20242023
Net income (loss)$52,744$(38,604)
Items excluded in the calculation of Non-GAAP operating income (loss):
Net investment (gains) losses(1)(1,903)(13,828)
Net investment gains (losses) attributable to SPCs in which no profit/loss is retained(2)1,7732,925
Transaction-related costs(3)320
Goodwill impairment44,110
Foreign currency exchange rate (gains) losses(4)(6,731)2,993
Non-operating income(5)(6,878)
Guaranty fund assessments (recoupments)(873)57
Non-core operations(6)3,331(1,683)
Pre-tax effect of exclusions(4,083)27,696
Tax effect, at 21%(7)(69)1,894
After-tax effect of exclusions(4,152)29,590
Non-GAAP operating income (loss)$48,592$(9,014)
Per diluted common share:
Net income (loss)$1.03$(0.73)
Effect of exclusions(0.08)0.56
Non-GAAP operating income (loss) per diluted common share$0.95$(0.17)

(1) Net investment gains (losses) recognized in earnings are primarily driven by changes in the value of investments that are marked to fair value each period, the nature and timing of which are unrelated to our normal operating results. Net investment gains (losses) for the year ended December 31, 2024 include the $6.5 million decrease to the contingent consideration liability during the second quarter of 2024. Net investment gains (losses) during the year ended December 31, 2023 include a gain of $5.0 million related to the remeasurement of the contingent consideration liability to fair value. See further discussion around the contingent consideration in Note 2 and Note 8 of the Notes to Consolidated Financial Statements and previous discussion under the heading "Contingent Consideration" in the Financing Activities and Related Cash Flows section.

(2) Net investment gains (losses) on investments related to SPCs are recognized in our Segregated Portfolio Cell Reinsurance segment. SPC results, including any net investment gain or loss, that are attributable to external cell participants are reflected in the SPC dividend expense (income). To be consistent with our exclusion of net investment gains (losses) recognized in earnings, we are excluding the portion of net investment gains (losses) that is included in the SPC dividend expense (income) which is attributable to the external cell participants.

(3) Transaction-related costs are attributable to actuarial consulting fees paid during the second quarter of 2024 in relation to the final determination of contingent consideration associated with the NORCAL acquisition. See previous discussion under the heading "Contingent Consideration" in the Financing Activities and Related Cash Flows section. We are excluding these costs as they do not reflect normal operating results and are unique and non-recurring in nature.

(4) Foreign currency exchange rate movements relate to foreign currency denominated loss reserves predominately associated with premium assumed from an international medical professional liability insured in our Specialty P&C segment. Our participation in this program has grown in recent years which has led to greater volatility in our results of operations even with nominal movements in exchange rates given the size of the reserve. We mitigate foreign exchange rate exposure on our Consolidated Balance Sheet by generally matching the currency and duration of associated investments to the corresponding loss reserves as well as utilizing foreign currency forward contracts. When we invest in foreign currency denominated available-for-sale fixed maturities, in accordance with GAAP, the change in market value due to changes in foreign currency exchange rates is reflected as a part of OCI. Conversely, the impact of changes in foreign currency exchange rates on loss reserves is reflected through net income (loss) as a component of other income (expense). Therefore, we believe foreign currency exchange rate gains (losses) in our Consolidated Statements of Income and Comprehensive Income in isolation are not indicative of our operating performance. To be consistent with our exclusion of foreign currency exchange rate gains (losses) recognized in earnings, we are excluding the changes in the value of the associated foreign currency forward contract. Additional information regarding our foreign currency forward contract is provided in Note 11 of the Notes to the Consolidated Financial Statements.

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(5) Non-operating income includes proceeds associated with the sale of our remaining ownership interest in the underwriting and operations entity associated with Syndicate 1729 to unrelated third parties recognized in other income in our Corporate segment. We are excluding these costs as they do not reflect normal operating results and are unique and non-recurring in nature.

(6) Non-core operations includes the net results from our Lloyd's Syndicates operations from our previous participation in Syndicate 1729 and Syndicate 6131 at Lloyd's of London, which is currently in run off. Net investment gains (losses) recognized in earnings associated with these investments are included in the adjustment for consolidated net investment gains (losses) as described in footnote 1. We are excluding these results from our Lloyd's Syndicates operations as they are irrelevant to our ongoing operations and do not qualify for Discontinued Operations under GAAP.

(7) Our statutory tax rate was applied to these items in calculating net income (loss), excluding the 2023 goodwill impairment loss which is not tax deductible. Changes in the contingent consideration liability are non-taxable and therefore had no associated income tax impact. The taxes associated with the net investment gains (losses) related to SPCs in our Segregated Portfolio Cell Reinsurance segment are paid by the individual SPCs and are not included in our consolidated tax provision or net income (loss); therefore, both the net investment gains (losses) from our Segregated Portfolio Cell Reinsurance segment and the adjustment to exclude the portion of net investment gains (losses) included in the SPC dividend expense (income) in the table above are not tax effected. There are no taxes associated with our Lloyd’s Syndicates operations in our consolidated tax provision due to the availability of net operating losses and the full valuation allowance recorded against the deferred tax assets. Accordingly, both the net investment gains (losses) and the adjustment to exclude the underwriting results and net investment income associated with our previous participation included in Lloyd's Syndicates operations in the table above are not tax effected.

Non-GAAP Operating ROE

Non-GAAP operating ROE is a financial measure that is calculated as Non-GAAP operating income (loss) divided by the average of beginning and ending total shareholders’ equity. As previously discussed, in calculating Non-GAAP operating income (loss), we have excluded the effects of certain items that do not reflect normal results. Non-GAAP operating ROE measures the overall after-tax profitability of our core insurance operations and shows how efficiently capital is being used; however, it should be considered in conjunction with ROE computed in accordance with GAAP. The following table is a reconciliation of ROE to Non-GAAP operating ROE for the years ended December 31, 2024 and 2023:

Year Ended December 31
20242023Change
ROE4.6%(3.5%)8.1pts
Effect of items excluded in the calculation of Non-GAAP operating ROE(0.4%)2.7%(3.1pts)
Non-GAAP operating ROE4.2%(0.8%)5.0pts

Non-GAAP operating ROE in 2024 increased by 5.0 percentage points as compared to 2023 driven by an improvement in prior accident year reserve development in our Specialty P&C and Workers' Compensation Insurance segments, an increase in our net investment result and an improvement in the current accident year net loss ratio in our Workers' Compensation Insurance segment. See previous discussions in this section under the heading "Executive Summary of Operations" and further discussion in our Segment Results sections that follow.

Non-GAAP Adjusted Book Value per Share

Book value per share is calculated as total GAAP shareholders’ equity divided by the total number of common shares outstanding at the balance sheet date. This ratio measures the net worth of the Company to shareholders on a per share basis.

Non-GAAP adjusted book value per share is a Non-GAAP measure widely used within the insurance sector and is calculated as total shareholders’ equity, excluding AOCI, divided by the total number of common shares outstanding at the balance sheet date. This Non-GAAP calculation measures the net worth of the Company to shareholders on a per share basis excluding AOCI to eliminate the temporary and potentially significant effects of fluctuations in interest rates on our fixed income portfolio; however, it should be considered in conjunction with book value per share computed in accordance with GAAP. Higher interest rates have led to significant unrealized holding losses on our available-for-sale fixed maturity investments resulting in volatility in AOCI in 2023 and 2024. See Note 12 of the Notes to Consolidated Financial Statements for additional information.

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The following table is a reconciliation of our book value per share to Non-GAAP adjusted book value per share at December 31, 2024 and December 31, 2023:

Book Value Per Share
Book Value Per Share at December 31, 2023$21.82
Less: AOCI Per Share(1)(4.01)
Non-GAAP Adjusted Book Value Per Share at December 31, 202325.83
Increase (decrease) to Non-GAAP Adjusted Book Value Per Share during the year ended December 31, 2024 attributable to:
Net income (loss)1.03
Non-GAAP Adjusted Book Value Per Share at December 31, 202426.86
Add: AOCI Per Share(1)(3.37)
Book Value Per Share at December 31, 2024$23.49
(1) Primarily the impact of accumulated unrealized investment gains (losses) on our available-for-sale fixed maturity investments. See Note 12 of the Notes to Consolidated Financial Statements for additional information.

Book value increased $1.67 per share from December 31, 2023 to December 31, 2024 were due to net income of $1.03 per share and the change in AOCI of $0.64 per share largely due to unrealized holding gains on our fixed income investment portfolio which flow directly to AOCI due to a decrease in interest rates since the end of 2023.

Segment Results - Specialty Property & Casualty

Our Specialty P&C segment focuses on Medical Professional Liability insurance and Medical Technology Liability insurance as discussed in Note 16 of the Notes to Consolidated Financial Statements. The Specialty P&C segment also includes the underwriting results from our participation in Syndicate 1729 and Syndicate 6131 at Lloyd's of London, which is currently in run off. We normally report results from our Lloyd's Syndicates operations on a one quarter delay; however, we have accelerated the reporting of certain events into the fourth quarter of 2024. See further discussion in this section under the heading "Losses and Loss Adjustment Expenses."

Segment results reflected pre-tax underwriting profit or loss from these insurance lines and included the amortization of certain purchase accounting adjustments. Segment results included the following:

Year Ended December 31
($ in thousands)20242023Change
Net premiums written$737,502$762,580$(25,078)(3.3%)
Net premiums earned$747,942$755,817$(7,875)(1.0%)
Other income (expense)4,3734,695(322)(6.9%)
Net losses and loss adjustment expenses(578,486)(624,809)46,323(7.4%)
Underwriting, policy acquisition and operating expenses(203,207)(195,303)(7,904)4.0%
Segment results$(29,378)$(59,600)$30,22250.7%
Net loss ratio77.3%82.7%(5.4pts)
Underwriting expense ratio27.2%25.8%1.4pts
Excluding Lloyd's Syndicates Operations:
Net loss ratio*76.9%83.2%(6.3pts)
Underwriting expense ratio*27.1%25.6%1.5pts
*Our Specialty P&C net loss and underwriting expense ratios as reported in 2024 include an underwriting loss of $4.7 million as compared to underwriting income of $0.6 million in 2023 associated with our Lloyd's Syndicates operations, which is currently in run-off. Given these underwriting results are irrelevant to our ongoing operations and do not qualify for Discontinued Operations under GAAP, we have excluded their impact from our calculation of the net loss and underwriting expense ratios in the table above.

Premiums Written

Changes in our premium volume within our Specialty P&C segment are generally driven by three primary factors: (1) the amount of new business written, (2) our retention of existing business and (3) the premium charged for business that is

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renewed, which is affected by rates charged and by the amount and type of coverage an insured chooses to purchase. In addition, premium volume may periodically be affected by shifts in the timing of renewals between periods.

The medical professional liability market, which accounts for a majority of the revenues in this segment, remains challenging as physicians continue joining hospitals or larger group practices and, therefore, are no longer purchasing individual or group policies in the standard market. In addition, some competitors have chosen to compete primarily on price. Those carriers have accumulated an excess of capital since approximately 2004 driven largely by drops in claims frequency. They now use that capital to generate higher investment returns supporting operating income over underwriting income. Both factors may impact our ability to write new business and retain existing business. Furthermore, the insurance and reinsurance markets have historically been cyclical, characterized by extended periods of intense price competition and other periods of reduced capacity. The medical professional liability market has historically been particularly affected by these cycles. Underwriting cycles are driven, among other reasons, by excess capacity available to compete for the business. Changes in the frequency and severity of losses may also affect the cycles of the insurance and reinsurance markets significantly.

Gross, ceded and net premiums written were as follows:

Year Ended December 31
($ in thousands)20242023Change
Gross premiums written$807,463$835,430$(27,967)(3.3%)
Less: Ceded premiums written69,96172,850(2,889)(4.0%)
Net premiums written$737,502$762,580$(25,078)(3.3%)

Gross Premiums Written

During the first quarter of 2024, we moved the podiatric, chiropractic and dental coverages from the Small Business Unit into HCPL, renaming the unit Medical Professional Liability. By combining these resources, we have a single unit dedicated to all of our healthcare insurance specialty areas and meeting customer needs more efficiently and effectively in order to better serve this market. As a result, we reorganized our presentation of gross premiums written by component and related metrics below to better align with the current internal management reporting structure within the segment. All prior period information has been recast to conform to the current period presentation.

Gross premiums written by component were as follows:

Year Ended December 31
($ in thousands)20242023Change
Medical Professional Liability (1)(2)$737,209$746,777$(9,568)(1.3%)
Medical Technology Liability (3)44,93644,5813550.8%
Lloyd's Syndicates (4)5,96919,572(13,603)(69.5%)
Other (5)19,34924,500(5,151)(21.0%)
Total Gross Premiums Written$807,463$835,430$(27,967)(3.3%)

(1) Medical Professional Liability premium was our greatest source of premium revenues in 2024 and 2023. The decrease in MPL premium for 2024 as compared to 2023 was driven by retention losses, partially offset by an increase in renewal pricing, new business written and, to a lesser extent, net timing differences of $2.0 million primarily related to the prior year renewal of a few large custom physician policies. Retention losses during 2024 generally reflect our pursuit of rate adequacy in a competitive market where other carriers may not have the same profitability objectives, recognize the rate need, or are attempting to gain market share despite near term underwriting losses which can be supported by investment returns from excess capital. Renewal pricing increases during 2024 reflect our response to the rising loss cost environment and new business written reflects the competitive market conditions. See a description of our MPL line of business and additional discussion on competitive market conditions in Part I Item 1. Business under the heading "Specialty Property and Casualty Segment" and "Competition," respectively.

(2) We offer alternative risk and self-insurance products on a customized basis. Our custom alternative risk solutions include a turnkey captive solution whereby we cede either all or a portion of the alternative market premium, net of reinsurance, to two SPCs of our wholly owned Cayman Islands reinsurance subsidiary, Inova Re, which is reported in our Segregated Portfolio Cell Reinsurance segment (see further discussion in the Ceded Premiums Written section that follows). Our MPL line of business for 2024 and 2023 included $4.2 million and $6.7 million, respectively, of alternative market gross premium written, which reflected our non-renewal of one program

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effective January 1, 2024, in which we do not participate in the underwriting results. Written premium related to this program totaled $3.4 million for 2023.

(3) Our Medical Technology Liability business is marketed throughout the U.S.; coverage is offered on a primary or excess basis, within specified limits, to manufacturers and distributors of medical technology and life sciences products including entities conducting human clinical trials. In addition to the previously listed factors that affect our premium volume, our Medical Technology Liability premium is also impacted by the sales volume of insureds. Our Medical Technology Liability premium remained relatively unchanged in 2024 as compared to 2023. Renewal pricing increases in 2024 are primarily due to changes in the sales volume and changes in exposure of certain insureds. Retention losses in 2024 are primarily attributable to insureds no longer needing coverage or going out of business, the broker losing the account, non-payment as well as merger activity within the industry.

(4) Our Lloyd's Syndicates business includes the results from our previous participation in Syndicate 1729 at Lloyd's of London, which is currently in run off. Effective September 2023, we elected to discontinue our participation in the results of Syndicate 1729 beginning with the 2024 underwriting year. For the 2023 underwriting year our participation in the results of Syndicate 1729 was approximately 5%. Our Lloyd’s Syndicates premium during 2024 reflected the impact of our ceased participation.

(5) This component of gross premiums written includes all other product lines within our Specialty P&C segment, primarily professional liability coverage to attorneys and their firms in select areas of practice.

New business written, retention and the change in renewal pricing for our Specialty P&C segment and by major component, excluding Lloyd's Syndicates, are shown in the table below:

Year Ended December 31
20242023
($ in millions)MPLMedical Technology LiabilityOtherSpecialty P&C SegmentMPLMedical Technology LiabilityOtherSpecialty P&C Segment
New business$26.8$4.1$0.5$31.4$56.4$7.7$0.7$64.8
Retention (1)84%91%74%84%85%82%84%85%
Change in renewal pricing (2)10%1%4%9%7%1%4%6%
(1) Calculated as annualized renewed premium divided by all annualized premium subject to renewal. Retention is affected by a number of factors. We may lose insureds to competitors or to alternative insurance mechanisms such as risk retention groups, captive arrangements or self-insurance entities (often when physicians join hospitals or large group practices) or due to pricing or other issues. We may choose not to renew an insured as a result of our underwriting evaluation. Insureds may also terminate coverage because they have left the practice of medicine for various reasons, principally for retirement, death or disability, but also for personal reasons. See further explanation of changes in retention above under the heading "Gross Premiums Written".
(2) We are committed to a rate structure that will allow us to fulfill our obligations to our insureds while generating competitive long-term returns for our shareholders. Our pricing continues to be based on expected losses as indicated by our historical loss data and available industry loss data. In recent years, this practice has resulted in rate increases and we anticipate further rate increases due to indications of increasing projected loss severity. Additionally, the pricing of our business includes the effects of filed rates, surcharges and discounts. Renewal pricing reflects changes in our exposure base, deductibles, self-insurance retention limits and other policy terms and conditions. See further explanation of changes in renewal pricing above under the heading "Gross Premiums Written".

Ceded Premiums Written

Ceded premiums represent the amounts owed to our reinsurers for their assumption of a portion of our losses. See previous discussion in our Liquidity and Capital Resources and Financial Condition section under the heading "Reinsurance" for information regarding our Medical Professional Liability and Medical Technology Liability excess of loss reinsurance arrangements.

We pay our reinsurers a ceding premium in exchange for their accepting the risk, and in certain of our excess of loss arrangements, the ultimate amount of which is determined by the loss experience of the business ceded, subject to certain minimum and maximum amounts. Given the length of time that it takes to resolve our claims, many years may elapse before all losses recoverable under a reinsurance arrangement are known. As a part of the process of estimating our loss reserve we also make estimates regarding the amounts recoverable under our reinsurance arrangements. As a result, we may have an adjustment to our estimate of expected losses and associated recoveries for prior year ceded losses under certain loss sensitive reinsurance agreements. Any changes to estimates of premiums ceded related to prior accident years are fully earned in the period the changes in estimates occur.

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Ceded premiums written were as follows:

Year Ended December 31
($ in thousands)20242023Change
Excess of loss reinsurance arrangements (1)$43,110$40,191$2,9197.3%
Premium ceded to SPCs (2)2,6495,640(2,991)(53.0%)
Other ceded premiums written (3)22,79729,445(6,648)(22.6%)
Adjustment to premiums owed under reinsurance agreements, prior accident years, net (4)1,405(2,426)3,831157.9%
Total ceded premiums written$69,961$72,850$(2,889)(4.0%)

(1)We generally reinsure risks under our excess of loss reinsurance arrangements pursuant to which the reinsurers agree to assume all or a portion of all risks that we insure above our individual risk retention levels. Premium due to reinsurers is based on a rate factor applied to gross premiums written subject to cession under the arrangement.

(2)As previously discussed, as a part of our alternative market solutions, all or a portion of certain medical professional liability premium written is ceded to SPCs in our Segregated Portfolio Cell Reinsurance segment under either excess of loss or quota share reinsurance agreements, depending on the structure of the individual program. See the Segment Results - Segregated Portfolio Cell Reinsurance section for further discussion on the cession to the SPCs from our Specialty P&C segment.

(3)Our other ceded premiums written is primarily comprised of various shared risk arrangements and cyber liability coverages.

(4)Given the length of time that it takes to resolve our claims, many years may elapse before all losses recoverable under a reinsurance arrangement are known. As a part of the process of estimating our loss reserve we also make estimates regarding the amounts recoverable under our reinsurance arrangements. As previously discussed, the premiums ultimately ceded under certain of our swing rated excess of loss reinsurance arrangements are subject to the losses ceded under the arrangements. As part of the review of our reserves for 2024, we recorded a net increase in our estimate of ceded premiums owed to reinsurers due to an increase in our estimate of expected losses and associated recoveries for certain prior year ceded losses, whereas we decreased our estimate of ceded premiums owed to reinsurers in 2023. Changes to estimates of premiums ceded related to prior accident years are fully earned in the period the changes in estimates occur.

Ceded Premiums Ratio

As shown in the table below, our ceded premiums ratio was affected in both 2024 and 2023 by revisions to our estimate of premiums owed to reinsurers related to coverages provided in prior accident years. The ceded premiums ratio was as follows:

Year Ended December 31
20242023Change
Ceded premiums ratio8.7%8.7%pts
Less the effect of adjustments in premiums owed under reinsurance agreements, prior accident years (as previously discussed)0.2%(0.3%)0.5pts
Ratio, current accident year8.5%9.0%(0.5pts)

The above table reflects ceded premiums written, excluding the effect of prior year ceded premium adjustments, as previously discussed, as a percent of gross premiums written. The decrease in our current accident year ceded premiums ratio for 2024 as compared to 2023 was primarily driven by our ceased participation in Syndicate 1729 for the 2024 underwriting year and, to a lesser extent, a decrease in premium ceded to SPCs.

Net Premiums Earned

Net premiums earned consist of gross premiums earned less the portion of earned premiums that we cede to our reinsurers for their assumption of a portion of our losses. Because premiums are generally earned pro rata over the entire policy period, fluctuations in premiums earned tend to lag those of premiums written. The majority of our policies carry a term of one year; however, some of our Medical Technology Liability policies have a multi-year term. Tail coverage premiums are generally 100% earned in the period written because the policies insure only incidents that occurred in prior periods and are not cancellable. Retroactive coverage premiums are 100% earned at the inception of the contract, as all of the associated underlying loss events occurred in the past. Additionally, any ceded premium changes due to changes to estimates of premiums owed under reinsurance agreements for prior accident years are fully earned in the period of change.

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Net premiums earned were as follows:

Year Ended December 31
($ in thousands)20242023Change
Gross premiums earned$818,751$826,907$(8,156)(1.0%)
Less: Ceded premiums earned70,80971,090(281)(0.4%)
Net premiums earned$747,942$755,817$(7,875)(1.0%)

Gross premiums earned decreased in 2024 as compared to 2023 driven by our ceased participation in Syndicate 1729 for the 2024 underwriting year and, to a lesser extent, the pro rata effect of a decrease in the volume of written premium during the preceding twelve months, primarily due to proactive actions taken in certain lines to improve profitability.

Ceded premiums earned during 2024 and 2023 included prior accident year ceded premium adjustments under swing rated reinsurance agreements (see previous discussion in footnote 4 under the heading "Ceded Premiums Written"). After removing the effect of the prior accident year ceded premium adjustment from both years, ceded premiums earned decreased by $4.1 million in 2024 as compared to 2023, driven by the pro rata effect of a decrease in premium ceded to SPCs during the preceding twelve months.

Losses and Loss Adjustment Expenses

The determination of calendar year losses involves the actuarial evaluation of incurred losses for the current accident year and the actuarial re-evaluation of incurred losses for prior accident years.

Accident year refers to the accounting period in which the insured event becomes a liability of the insurer. For claims-made policies, which represent the majority of the premiums written in our Specialty P&C segment, the insured event generally becomes a liability when the event is first reported to us and the policy that is in effect at that time covers the claim. For occurrence policies, the insured event becomes a liability when the event takes place even though the claim may be reported to us at a later date. For retroactive coverages, the insured event becomes a liability at inception of the underlying contract. We believe that measuring losses on an accident year basis is the best measure of the underlying profitability of the premiums earned in that period, since it associates policy premiums earned with the estimate of the losses incurred related to those policy premiums.

The following tables summarize calendar year net loss ratios for our Specialty P&C segment by separating losses between the current accident year and all prior accident years, including each line of business' contribution to the change in the segment's current accident year net loss ratio.

Net Loss Ratios (1)
Year Ended December 31
20242023Change
Calendar year net loss ratio77.3%82.7%(5.4pts)
Less impact of prior accident years on the net loss ratio(5.0%)0.1%(5.1pts)
Current accident year net loss ratio82.3%82.6%(0.3pts)
(In percentage points)Increase (Decrease) 2024 versus 2023
Estimated ratio increase (decrease) attributable to:
Medical Professional Liability (2)(0.6 pts)
Medical Technology Liability0.1 pts
Other0.2 pts
Decrease in current accident year net loss ratio(0.3 pts)

(1)Net losses, as specified, divided by net premiums earned.

(2)For the year ended December 31, 2024, our MPL line of business current accident year net loss ratio, which represents the largest product line within our Specialty P&C segment, improved 0.6 percentage points as compared

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to 2023 (as shown in the table above). The change in our MPL current accident year net loss ratio was primarily attributable to the following:

(In percentage points)Increase (Decrease) 2024 versus 2023
Estimated ratio increase (decrease) attributable to:
Ceded Premium Adjustment, Prior Accident Years (1)0.5 pts
Change in ULAE0.6 pts
All other, net(1.7 pts)
Decrease in MPL current accident year net loss ratio(0.6 pts)
(1) See previous discussion in footnote 4 under the heading "Ceded Premiums Written" for additional information.

•Excluding the impact of the items specifically identified in the table above, our MPL line of business current accident year net loss ratio for 2024 as compared to 2023 improved 1.7 percentage points driven by our continued underwriting and pricing actions which have resulted in our decrease to certain expected loss ratios during the first quarter of 2024 and, to a lesser extent, a decrease in our reserves related to DDR coverage endorsements due to a decrease in business eligible for tail coverage. In both 2024 and 2023, we decreased our reserves related to DDR coverage endorsements; however, the adjustment was greater in 2024 as compared to 2023. The improvement in our current accident year net loss ratio was partially offset by higher than anticipated loss severity trends in select jurisdictions which have resulted in an increase to certain expected loss ratios during the fourth quarter of 2024 as well as changes in the mix of business.

•ULAE are costs that cannot be attributed to processing a specific claim and are allocated to net losses and loss adjustment expenses from underwriting and operating expenses. In 2024, ULAE increased due to higher compensation-related costs in our claims department.

We re-evaluate our previously established reserve each quarter based upon the most recently completed actuarial analysis supplemented by any new analysis, information or trends that have emerged since the date of that study. We also take into account currently available industry trend information.

We recognized net favorable (unfavorable) prior accident year reserve development as follows:

Year Ended December 31
($ in thousands)20242023Change
Total net favorable (unfavorable) reserve development$36,932$(328)$37,26011,359.8%

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The following table shows net favorable (unfavorable) development by component for the years ended December 31, 2024 and 2023:

•MPL: The loss environment in our MPL line of business continues to be challenging in many jurisdictions, as claim costs are pressured by social inflation and higher than anticipated loss severity trends that started to reemerge in the fourth quarter of 2022. We continue to monitor the impact that these trends have on our open case reserves and prior accident year development. While higher loss severity trends remained challenging in 2024, we recognized net favorable reserve development for the year ended December 31, 2024 reflecting overall favorable trends in claim closing patterns relative to expectations, principally related to accident years 2019 through 2021.

In the first quarter of 2023, we strengthened case reserves related to four large claims, resulting in $10.1 million of unfavorable development, primarily related to NORCAL's accident years 2016 and 2020, partially offset by $0.5 million of net favorable reserve development recognized during the fourth quarter of 2023, primarily related to accident years 2018 and prior in our legacy book. The contingent consideration associated with the NORCAL acquisition was dependent upon the after-tax development of NORCAL’s 2020 and prior accident year reserves from December 31, 2020 to December 31, 2023. In the fourth quarter of 2023, we recognized unfavorable development in NORCAL’s 2020 and prior accident year reserves which was entirely offset by favorable development recognized in NORCAL’s 2021 and 2022 accident year reserves since acquisition. While these adjustments to NORCAL’s reserves had no impact to the segment’s net losses or net loss ratio, they contributed to the decrease in the fair value of the contingent consideration liability of $3.5 million in 2023 which was recorded as an offset to operating expenses in the segment. See further discussion on the contingent consideration in the Financing Activities and Related Cash Flows section under the heading "Contingent Consideration."

•Medical Technology Liability: During both 2024 and 2023, we recognized net favorable reserve development due to lower than anticipated loss emergence. Net favorable development recognized in 2024 principally related to accident years 2022 and 2023 whereas development recognized in 2023 principally related to accident years 2020 through 2022.

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•Lloyd's Syndicates Operations (Participation Discontinued): We normally report results from our Lloyd's Syndicates operations on a one quarter delay; however, during the fourth quarter of 2024, Syndicate 6131 increased its IBNR reserve associated with the 2021 underwriting year for exposures related to aviation coverages in connection with Russia's invasion of Ukraine. While this event would normally be reported in our first quarter of 2025 results, given the availability and significance of this event, we have accelerated the reporting of our allocated share of these losses of $5.3 million into the fourth quarter of 2024, consistent with our policy of recognizing significant losses in the period in which they become known to us. The remaining net unfavorable reserve development during 2024 and 2023 was driven by higher than expected losses and development on certain large claims, primarily aviation and catastrophe related losses.

•Purchase Accounting Amortization: Net prior year reserve development for both periods presented included amortization of the purchase accounting fair value adjustment on NORCAL's assumed net reserve and amortization of the negative VOBA associated with NORCAL's DDR reserve which is recorded as a reduction to net losses and loss adjustment expenses.

A detailed discussion of factors influencing our recognition of loss development is included in our Critical Accounting Estimates section under the heading "Reserve for Losses and Loss Adjustment Expenses." Assumptions used in establishing our reserve are regularly reviewed and updated by management as new data becomes available. Any adjustments necessary are reflected in the then current operations. Due to the size of our reserve, even a small percentage adjustment to the assumptions can have a material effect on our results of operations for the period in which the change is made.

Underwriting, Policy Acquisition and Operating Expenses

Our Specialty P&C segment underwriting, policy acquisition and operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20242023Change
DPAC amortization$102,125$101,691$4340.4%
Management fees3,8453,894(49)(1.3%)
Other underwriting and operating expenses97,23789,7187,5198.4%
Total$203,207$195,303$7,9044.0%

DPAC amortization increased in 2024 as compared to 2023 primarily driven by an increase in capitalized compensation-related costs and, to a lesser extent, a decrease in ceding commission income, which is an offset to expense, partially offset by a decrease in brokerage expenses.

Management fees are charged pursuant to a management agreement by the Corporate segment to the core domestic operating subsidiaries within our Specialty P&C segment for services provided based on the extent to which services are provided to the subsidiary and the amount of premium written by the subsidiary. While the terms of the management agreement were generally consistent between 2024 and 2023, fluctuations in the amount of premium written by each subsidiary can result in corresponding variations in the management fee charged to each subsidiary during a particular period.

Other underwriting and operating expenses increased in 2024 as compared to 2023 primarily attributable to the following:

•Prior year impact of certain one-time items that are unique or non-recurring in nature recorded during 2023 that resulted in a benefit to operating expenses. We recognized a claim for a payroll tax refund of $3.8 million related to the employee retention credit and a reduction to operating expenses of $3.5 million related to the reduction to the contingent consideration liability. See additional discussion on the ERC in Note 1 of the Notes to Consolidated Financial Statements and previous discussion on contingent consideration in the Financing Activities and Related Cash Flows section under the heading "Contingent Consideration."

•An increase in compensation-related expenses, partially offset by lower professional fees, a decrease in Syndicate 1729's operating expenses due to our ceased participation for the 2024 underwriting year and lower facilities expenses. The increase in compensation-related costs in 2024 as compared to 2023 was primarily due to higher amounts accrued for performance-related incentive plans due to the improvement of the related performance metrics. The decrease in professional fees in 2024 was driven by a reduction in fees associated with a data analytics services agreement, a decrease in consulting fees and lower external audit fees. The remaining variance in other underwriting and operating expenses for 2024 as compared to 2023 was comprised of individually insignificant components.

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Underwriting Expense Ratio (the Expense Ratio)

Our expense ratio for the Specialty P&C segment was as follows:

Year Ended December 31
20242023Change
Underwriting expense ratio27.2%25.8%1.4pts

The change in our expense ratio in 2024 as compared to 2023 was primarily attributable to the following:

(In percentage points)Increase (Decrease) 2024 versus 2023
Estimated ratio increase (decrease) attributable to:
Change in Net Premiums Earned and DPAC amortization0.2 pts
Prior Year One-Time Items1.0 pts
Lloyd's Syndicates Operations(0.1 pts)
All other, net0.3 pts
Increase in the underwriting expense ratio1.4 pts

Excluding the impact of the items specifically identified in the table above, our expense ratio was relatively unchanged in 2024 as compared to 2023 as the increase in compensation-related expenses was partially offset by lower professional fees and facilities expenses.

Segment Results - Workers' Compensation Insurance

Our Workers' Compensation Insurance segment includes workers' compensation products provided to employers generally with 1,000 or fewer employees, as discussed in Note 16 of the Notes to Consolidated Financial Statements. Segment results included the following:

Year Ended December 31
($ in thousands)20242023Change
Net premiums written$166,223$162,285$3,9382.4%
Net premiums earned$167,610$160,034$7,5764.7%
Other income1,8871,854331.8%
Net losses and loss adjustment expenses(128,483)(139,322)10,839(7.8%)
Underwriting, policy acquisition and operating expenses(61,999)(55,061)(6,938)12.6%
Segment results$(20,985)$(32,495)$11,51035.4%
Net loss ratio76.7%87.1%(10.4 pts)
Underwriting expense ratio37.0%34.4%2.6 pts

Premiums Written

Our workers’ compensation premium volume is driven by five primary factors: (1) the amount of new business written, (2) retention of our existing book of business, (3) premium rates charged on our renewal book of business, (4) changes in payroll exposure and (5) audit premium.

Gross, ceded and net premiums written were as follows:

Year Ended December 31
($ in thousands)20242023Change
Gross premiums written$243,404$246,857$(3,453)(1.4%)
Less: Ceded premiums written77,18184,572(7,391)(8.7%)
Net premiums written$166,223$162,285$3,9382.4%

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Gross Premiums Written

Gross premiums written by product were as follows:

Year Ended December 31
($ in thousands)20242023Change
Traditional business:
Guaranteed cost$141,231$137,088$4,1433.0%
Policyholder dividend21,64122,829(1,188)(5.2%)
Deductible5,5485,0614879.6%
Retrospective4,8532,7492,10476.5%
Other5,9506,376(426)(6.7%)
Change in EBUB estimate2,9002,900%
Total traditional business(1)182,123177,0035,1202.9%
Alternative market business(2)61,28169,854(8,573)(12.3%)
Total$243,404$246,857$(3,453)(1.4%)

(1) Gross premiums written increased during 2024 as compared to 2023 driven by higher renewal business and audit premium. Renewal business reflected an improvement in renewal pricing and an increase in payroll exposure. Additionally, renewal business included the renewal of certain policies as traditional business that were previously written in one of the alternative market programs in our Segregated Portfolio Cell Reinsurance segment, totaling $3.0 million for 2024. Gross premiums written in our traditional business also reflected the continuation of competitive workers' compensation market conditions, which contributed to a reduction in our renewal retention rate and the impact of compounded state loss cost reductions in our core operating territories.

(2) A majority of alternative market premiums are ceded to SPCs in our Segregated Portfolio Cell Reinsurance segment. See further discussion on alternative market gross premiums written in our Segment Results - Segregated Portfolio Cell Reinsurance section under the heading "Gross Premiums Written" that follows. We retained twenty-one of the twenty-four (five in the fourth quarter) workers' compensation alternative market programs that were up for renewal during the year ended December 31, 2024. Effective January 1, 2024, two programs were non-renewed and placed into run-off; however, as the underlying policies expired in one program, a majority of those policies renewed as traditional business in our Workers' Compensation Insurance segment, as previously discussed. The other program, in which we do not participate in the underwriting results, assumed both workers' compensation insurance and medical professional liability insurance and we elected to non-renew this program. Additionally, we retroactively non-renewed a program during fourth quarter of 2024 (originally renewed in the second quarter) due to the non-renewal of a large policy written in the program.

New business, audit premium, renewal retention and renewal price changes for our traditional business and the alternative market business are shown in the table below:

Year Ended December 31
20242023
($ in millions)Traditional BusinessAlternative Market BusinessSegment ResultsTraditional BusinessAlternative Market BusinessSegment Results
New business$17.5$3.5$21.0$22.0$4.2$26.2
Audit premium (excluding EBUB)$12.1$3.7$15.8$9.1$3.6$12.7
Retention(1)87%84%86%88%93%89%
Change in renewal pricing (2)(2%)(1%)(1%)(5%)(5%)(5%)
(1) We calculate our workers' compensation retention as renewed premium divided by premium available to renew. Beginning in the fourth quarter of 2024, we have revised our calculation of retention to remove the impacts of audit premium. Previously, premium available to renew in the calculation included premium adjustments related to audits of expired policies which impacted retention. Prior periods have been recast to conform to the current period calculation. Our retention rate can be impacted by various factors, including price or other competitive issues, insureds being acquired, or a decision not to renew based on our underwriting evaluation.
(2) The pricing of our business includes an assessment of the underlying policy exposure and market conditions. We continue to base our pricing on expected losses, as indicated by our historical loss data.

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Ceded Premiums Written

Ceded premiums written were as follows:

Year Ended December 31
($ in thousands)20242023Change
Premiums ceded to SPCs(1)$55,255$64,619$(9,364)(14.5%)
Premiums ceded to external reinsurers(2)15,90014,7181,1828.0%
Other(3)6,0265,23579115.1%
Total ceded premiums written$77,181$84,572$(7,391)(8.7%)
(1) Represents alternative market business that is ceded under 100% quota share reinsurance agreements to the SPCs in our Segregated Portfolio Cell Reinsurance segment. See further discussion on alternative market gross premiums written in our Segment Results - Segregated Portfolio Cell Reinsurance section under the heading "Gross Premiums Written" that follows.
(2) Premiums ceded under our traditional reinsurance treaty are based on premiums earned during the treaty period. The increase for the year ended December 31, 2024 as compared to 2023 reflected the increase in premiums earned and a higher average reinsurance rate, partially offset by lower reinstatement premium recognized of $0.7 million in 2024 as compared to $1.6 million in 2023 related to reserve increases on prior year reinsured claims.
(3) This component of ceded premiums written primarily represents premiums ceded to unaffiliated captive insurers represents alternative market business for two programs that are ceded under 100% quota share reinsurance agreements.

Ceded Premiums Ratio

Ceded premiums ratio was as follows:

Year Ended December 31
20242023Change
Ceded premiums ratio, as reported32.3%34.6%(2.3pts)
Less the effect of:
Premiums ceded to SPCs (100%)20.9%23.6%(2.7pts)
Other2.4%2.2%0.2pts
Ceded premiums ratio (related to external reinsurance), less the effects of above9.0%8.8%0.2pts

The above table reflects traditional ceded premiums earned as a percent of traditional gross premiums earned. As discussed above, premiums ceded under our traditional reinsurance treaty are based on premiums earned during the treaty period. The increase in the ceded premiums ratio in 2024 as compared to 2023 primarily reflects a higher average reinsurance rate, partially offset by lower reinstatement premium (see previous discussion on reinstatement premium in footnote 2 under the heading "Ceded Premiums Written").

Net Premiums Earned

Net premiums earned consist of gross premiums earned less the portion of earned premiums that we cede to SPCs in our Segregated Portfolio Cell Reinsurance segment, external reinsurers (including changes related to the return premium and revenue share estimates) and the unaffiliated captive insurers. Because premiums are generally earned pro rata over the entire policy period, fluctuations in premiums earned tend to lag those of premiums written. Our workers’ compensation policies are twelve month term policies, and premiums are earned on a pro rata basis over the policy period. Net premiums earned also include premium adjustments related to the audit of our insureds' payrolls, changes in our estimates related to EBUB and premium adjustments related to retrospectively-rated policies. Payroll audits are conducted subsequent to the end of the policy period and any related premium adjustments are recorded as fully earned in the current period. We evaluate our estimates related to EBUB and retrospectively-rated premium adjustments on a quarterly basis with any adjustments being included in written and earned premium in the current period.

Net premiums earned were as follows:

Year Ended December 31
($ in thousands)20242023Change
Gross premiums earned$247,745$244,873$2,8721.2%
Less: Ceded premiums earned80,13584,839(4,704)(5.5%)
Net premiums earned$167,610$160,034$7,5764.7%

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Net premiums earned increased during the year ended December 31, 2024 as compared to 2023 primarily driven by higher renewal premium, including the renewal of certain policies as traditional business that were previously written in one of the alternative market programs in our Segregated Portfolio Cell Reinsurance segment, higher audit premium and, to a lesser extent, lower reinstatement premium, partially offset by the continuation of competitive market conditions. See previous discussion on reinstatement premium in footnote 2 under the heading "Ceded Premiums Written.

Losses and Loss Adjustment Expenses

We estimate our current accident year loss and loss adjustment expenses by developing actual reported losses using historical loss development factors, adjusted to reflect current and expected trends based on various internal analyses and supplemental information. The following table summarizes calendar year net loss ratios by separating losses between the current accident year and all prior accident years. Calendar year and current accident year net loss ratios by component were as follows:

Year Ended December 31
20242023Change
Calendar year net loss ratio76.7%87.1%(10.4pts)
Less impact of prior accident years on the net loss ratio(0.3%)5.8%(6.1pts)
Current accident year net loss ratio77.0%81.3%(4.3pts)

The 2024 current accident year net loss ratio improved 4.3 points as compared to 2023. During the second half of 2023, we increased our current accident year net loss ratio to reflect higher than expected loss trends observed in our average cost per claim. While we continue to observe, and therefore reflect, higher medical loss cost trends, we have seen these trends begin to moderate during 2024, including a reduction in the 2024 average cost per claim.

Calendar year reported losses in excess of our per occurrence reinsurance retention decreased $8.3 million in 2024 as compared to 2023, reflecting a reduction in severity-related claim activity. We recognized losses within the AAD totaling $2.0 million for the year ended December 31, 2024 as compared to $5.8 million in 2023, reflecting the elimination of the AAD from our reinsurance treaty renewal effective May 1, 2024. Our exposure to losses within the AAD were recognized at the maximum liability for each reinsurance contract year, based on historical reinsured loss trends. During the 2024 fourth quarter, we reduced the AAD liability by $0.5 million based on an evaluation of open claims for contract years in which actual losses are within the maximum liability. Actual losses within the AAD continue to be less than the maximum liability after the $0.5 million reduction, but the ultimate liability could increase or decrease based on changes in future estimates of claims within the AAD.

We recognized net favorable prior accident year reserve development of $0.5 million for the year ended December 31, 2024 as compared to $9.3 million of net unfavorable prior accident year reserve development for 2023. In 2024, net favorable reserve development was driven by favorable prior accident year reserve development of $1.6 million, including the reduction of the AAD liability, as discussed above, partially offset by an adjustment to aggregate losses assumed from the Segregated Portfolio Cell Reinsurance segment of $1.1 million. The net favorable development recognized in 2024 reflected overall favorable trends in claim closing patterns in accident years 2017 through 2019 and 2023. Net unfavorable development recognized in 2023 reflected higher than expected average claim costs primarily in the 2022 accident year and a large claim from the 1997 accident year.

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Underwriting, Policy Acquisition and Operating Expenses

Underwriting, policy acquisition and operating expenses include the amortization of commissions, premium taxes and underwriting salaries, which are capitalized and deferred over the related workers’ compensation policy period, net of ceding commissions earned. The capitalization of underwriting salaries can vary as they are subject to the success rate of our contract acquisition efforts. These expenses also include a management fee charged by our Corporate segment, which represents intercompany charges pursuant to a management agreement. The management fee is based on the extent to which services are provided to the subsidiary and the amount of premium written by the subsidiary.

Our Workers' Compensation Insurance segment underwriting, policy acquisition and operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20242023Change
DPAC amortization$29,072$29,486$(414)(1.4%)
Management fees1,8201,846(26)(1.4%)
Other underwriting and operating expenses42,05538,0144,04110.6%
SPC ceding commission offset(10,948)(14,285)3,337(23.4%)
Total$61,999$55,061$6,93812.6%

DPAC amortization decreased for the year ended December 31, 2024 as compared to 2023 reflecting the recovery of guaranty fund assessments totaling $1.0 million during 2024. After removing the effect of the guaranty fund recoupments, DPAC amortization increased by $0.6 million during 2024 reflecting an increase in gross premiums earned.

Other underwriting and operating expenses increased for the year ended December 31, 2024 as compared to 2023, primarily reflecting an increase in compensation-related and information technology costs. The increase in compensation-related costs primarily reflected higher amounts accrued for performance-related incentive plans due to an improvement in the related performance metrics and an increase in salaries due to annual merit adjustments. Information technology costs increased during 2024 reflecting our investment in initiatives that will enhance underwriting and claim operating efficiencies.

As previously discussed, alternative market premiums written by our Workers' Compensation Insurance segment are 100% ceded, less a ceding commission, to either the SPCs in our Segregated Portfolio Cell Reinsurance segment or unaffiliated captive insurers. The ceding commission charged to the SPCs consists of an amount for fronting fees, cell rental fees, commissions, premium taxes, claims administration fees and risk management fees. The fronting fees, commissions, premium taxes and risk management fees are recorded as an offset to underwriting, policy acquisition and operating expenses. Cell rental fees are recorded as a component of other income and claims administration fees are recorded as ceded ULAE. SPC ceding commissions earned decreased for the year ended December 31, 2024 as compared to 2023, primarily reflecting an adjustment to ceding commissions charged to the SPCs in prior periods related to certain fees as well as the non-renewal of the two alternative market programs effective January 1, 2024 and the related decrease in ceded premium.

Underwriting Expense Ratio (the Expense Ratio)

The underwriting expense ratio included the impact of the following:

Year Ended December 31
20242023Change
Underwriting expense ratio, as reported37.0%34.4%2.6pts
Less estimated ratio increase (decrease) attributable to:
Impact of ceding commissions received from SPCs5.5%4.3%1.2pts
Impact of audit premium(2.1%)(2.0%)(0.1pts)
Impact of reinstatement premium%0.3%(0.3pts)
Underwriting expense ratio, less listed effects33.6%31.8%1.8pts

Excluding the items noted in the table above, the expense ratio increased for the year ended December 31, 2024 primarily reflecting the increase in other underwriting and operating expenses and lower ceding commission income, which is an offset to expense, as previously discussed.

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Segment Results - Segregated Portfolio Cell Reinsurance

The Segregated Portfolio Cell Reinsurance segment includes the results (underwriting profit or loss, plus investment results, net of U.S. federal income taxes) of SPCs at Inova Re and Eastern Re, our Cayman Islands SPC operations, as discussed in Note 17 of the Notes to Consolidated Financial Statements. SPCs are segregated pools of assets and liabilities that provide an insurance facility for a defined set of risks. Assets of each SPC are solely for the benefit of that individual cell and each SPC is solely responsible for the liabilities of that individual cell. Assets of one SPC are statutorily protected from the creditors of the others. As of December 31, 2024, there were twenty-six (six inactive) SPCs. Effective January 1, 2024, two SPCs were non-renewed and placed into run-off. As the underlying policies expired that were previously written in one of the programs, a majority of those policies renewed as traditional business in our Workers' Compensation Insurance segment. The other program, in which we do not participate in the underwriting results, assumed both workers' compensation insurance and medical professional liability insurance. For the year ended December 31, 2023, these SPCs had workers' compensation and medical professional liability premiums written totaling $6.4 million and $3.4 million, respectively. Additionally, we retroactively non-renewed a program during the fourth quarter of 2024 (originally renewed in the second quarter) due to the non-renewal of a large policy written in the program. The expiring premium on the policies that non-renewed totaled $1.8 million.

Segment results reflect our share of the underwriting and investment results of the SPCs in which we participate, and included the following:

Year Ended December 31
($ in thousands)20242023Change
Net premiums written$49,950$61,129$(11,179)(18.3%)
Net premiums earned$52,698$61,546$(8,848)(14.4%)
Net investment income3,6082,2891,31957.6%
Net investment gains (losses)2,3693,680(1,311)(35.6%)
Other income (expenses)19514280.0%
Net losses and loss adjustment expenses(32,466)(36,363)3,897(10.7%)
Underwriting, policy acquisition and operating expenses(18,063)(20,457)2,394(11.7%)
SPC U.S. federal income tax (expense) benefit (1)(1,766)(1,629)(137)8.4%
SPC net results6,3999,071(2,672)(29.5%)
SPC dividend (expense) income (2)(4,444)(6,234)1,790(28.7%)
Segment results (3)$1,955$2,837$(882)(31.1%)
Net loss ratio61.6%59.1%2.5 pts
Underwriting expense ratio34.3%33.2%1.1 pts
(1) Represents the provision for U.S. federal income taxes for SPCs at Inova Re, which have elected to be taxed as a U.S. corporation under Section 953(d) of the Internal Revenue Code. U.S. federal income taxes are included in the total SPC net results and are paid by the individual SPCs.
(2) Represents the net (profit) loss attributable to external cell participants.
(3) Represents our share of the net profit (loss) and OCI of the SPCs in which we participate.

Premiums Written

Premiums in our Segregated Portfolio Cell Reinsurance segment are assumed from either our Workers' Compensation Insurance or Specialty P&C segments. Premium volume is driven by five primary factors: (1) the amount of new business written, (2) retention of the existing book of business, (3) premium rates charged on the renewal book of business and, for workers' compensation business, (4) changes in payroll exposure and (5) audit premium.

Gross, ceded and net premiums written were as follows:

Year Ended December 31
($ in thousands)20242023Change
Gross premiums written$57,904$70,259$(12,355)(17.6%)
Less: Ceded premiums written7,9549,130(1,176)(12.9%)
Net premiums written$49,950$61,129$(11,179)(18.3%)

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Gross Premiums Written

Gross premiums written reflected reinsurance premiums assumed by component as follows:

Year Ended December 31
($ in thousands)20242023Change
Workers' compensation$55,255$64,619$(9,364)(14.5%)
Medical professional liability2,6495,640(2,991)(53.0%)
Gross Premiums Written$57,904$70,259$(12,355)(17.6%)

Gross premiums written for the years ended December 31, 2024 and 2023 were primarily comprised of workers' compensation coverages assumed from our Workers' Compensation Insurance segment. Workers' compensation and medical professional liability gross premiums written decreased during the year ended December 31, 2024 as compared to 2023 due to the non-renewal of three programs, as previously discussed.

We retained nineteen of the twenty-two workers' compensation programs and two of the three medical professional liability programs up for renewal for the year ended December 31, 2024.

New business, audit premium, retention and renewal price changes for the assumed workers' compensation premium is shown in the table below:

Year Ended December 31
($ in millions)20242023
New business$3.5$4.2
Audit premium$3.7$3.6
Retention(1)84%93%
Change in renewal pricing(2)(1%)(5%)
(1) We calculate our workers' compensation retention as renewed premium divided by premium available to renew. Beginning in the fourth quarter of 2024, we have revised our calculation of retention to remove the impacts of audit premium. Previously, premium available to renew in the calculation included premium adjustments related to audits of expired policies which impacted retention. Prior periods have been recast to conform to the current period calculation. Our retention rate can be impacted by various factors, including price or other competitive issues, insureds being acquired, or a decision not to renew based on our underwriting evaluation.
(2) The pricing of our business includes an assessment of the underlying policy exposure and market conditions. We continue to base our pricing on expected losses, as indicated by our historical loss data.

Ceded Premiums Written

Ceded premiums written were as follows:

Year Ended December 31
($ in thousands)20242023Change
Ceded premiums written$7,954$9,130$(1,176)(12.9%)

For the workers' compensation business, each SPC has in place its own external reinsurance coverage. The medical professional liability business is assumed net of reinsurance from our Specialty P&C segment; therefore, there are no ceded premiums related to the medical professional liability business reflected in the table above. Premiums ceded under our SPC reinsurance treaty are based on premiums written during the treaty period. The change in ceded premiums written in 2024 as compared to 2023 primarily reflected the decrease in workers' compensation gross premiums written and the impact of rate changes under the external reinsurance treaty. External reinsurance rates vary based on the alternative market program.

Ceded Premiums Ratio

Ceded premiums ratio was as follows:

Year Ended December 31
20242023Change
Ceded premiums ratio14.4%14.1%0.3pts

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The above table reflects ceded premiums as a percent of gross premiums written for the workers' compensation business only; medical professional liability business is assumed net of reinsurance, as discussed above. The ceded premiums ratio reflects the weighted average reinsurance rates of all SPC programs.

Net Premiums Earned

Net premiums earned consist of gross premiums earned less the portion of earned premiums that the SPCs cede to external reinsurers. Because premiums are generally earned pro rata over the entire policy period, fluctuations in premiums earned tend to lag those of premiums written. Policies ceded to the SPCs are twelve month term policies and premiums are earned on a pro rata basis over the policy period. Net premiums earned also include premium adjustments related to the audit of workers' compensation insureds' payrolls. Payroll audits are conducted subsequent to the end of the policy period and any related adjustments are recorded as fully earned in the current period.

Gross, ceded and net premiums earned were as follows:

Year Ended December 31
($ in thousands)20242023Change
Gross premiums earned$60,959$70,706$(9,747)(13.8%)
Less: Ceded premiums earned8,2619,160(899)(9.8%)
Net premiums earned$52,698$61,546$(8,848)(14.4%)

The decrease in net premiums earned during the year ended December 31, 2024 as compared to 2023 primarily reflected the non-renewal of two SPCs effective January 1, 2024.

Losses and Loss Adjustment Expenses

The following table summarizes the calendar year net loss ratios by separating losses between the current accident year and all prior accident years. The current accident year net loss ratio reflects the aggregate loss ratio for all programs. Loss reserves and associated reinsurance are estimated for each program on a quarterly basis. Each SPC has in place its own reinsurance agreement, and the attachment point of aggregate reinsurance coverage varies by program. Due to the size of some of the programs, quarterly loss results, including changes in estimated aggregate reinsurance, can create volatility in the current accident year net loss ratio from period to period.

Calendar year and current accident year net loss ratios for the years ended December 31, 2024 and 2023 were as follows:

Year Ended December 31
20242023Change
Calendar year net loss ratio61.6%59.1%2.5pts
Less impact of prior accident years on the net loss ratio(5.2%)(6.4%)1.2pts
Current accident year net loss ratio66.8%65.5%1.3pts

The current accident year net loss ratio increased in 2024 as compared to 2023, primarily reflecting an increase in claim severity.

Calendar year workers' compensation incurred losses (excluding IBNR) ceded to our external reinsurers increased $8.9 million for the year ended December 31, 2024 as compared to 2023. Current accident year ceded incurred losses (excluding IBNR) increased $9.5 million for the year ended December 31, 2024 as compared to 2023. The 2024 ceded loss activity reflects an increase in average claim severity and reported large loss frequency.

We recognized net favorable prior year reserve development of $2.8 million and $4.0 million for the years ended December 31, 2024 and 2023, respectively. The development in 2024 includes net favorable development in the workers' compensation business of $3.1 million and net unfavorable development of $0.3 million in the medical professional liability business. The net favorable development related to the workers' compensation business in 2024 reflected overall favorable trends in claim closing patterns primarily in accident years 2018 through 2023. The net unfavorable development in the medical professional liability business in 2024 primarily reflected higher than expected claim frequency in the program that assumed both workers' compensation and medical professional liability insurance, which was non-renewed effective January 1, 2024. We do not participate in the underwriting results of this program.

The development in 2023 includes net favorable development in the workers' compensation business of $5.3 million, partially offset by net unfavorable development of $1.3 million in the medical professional liability business. The net favorable development in the workers' compensation business in 2023 reflected overall favorable trends in claim closing patterns

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primarily in accident years 2016 through 2021. The net unfavorable development in the medical professional liability business in 2023 reflected higher than expected claim frequency in one program. We do not participate in the underwriting results of this program.

Underwriting, Policy Acquisition and Operating Expenses

Our Segregated Portfolio Cell Reinsurance segment underwriting, policy acquisition and operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20242023Change
DPAC amortization$16,354$18,371$(2,017)(11.0%)
Other underwriting and operating expenses1,7092,086(377)(18.1%)
Total$18,063$20,457$(2,394)(11.7%)

DPAC amortization primarily represents ceding commissions, which vary by program and are paid to our Workers' Compensation Insurance and Specialty P&C segments for premiums assumed. Ceding commissions include an amount for fronting fees, commissions, premium taxes and risk management fees, which are reported as an offset to underwriting, policy acquisition and operating expenses within our Workers' Compensation Insurance and Specialty P&C segments. In addition, ceding commissions paid to our Workers' Compensation Insurance segment include cell rental fees which are recorded as other income and claims administration fees which are recorded as ceded ULAE within our Workers' Compensation Insurance segment. The decrease in DPAC amortization in 2024 as compared to 2023 primarily reflected a decrease in earned premium, as discussed above under the heading "Net Premiums Earned."

Other underwriting and operating expenses primarily include bank fees, professional fees, changes in the allowance for expected credit losses and policyholder dividend expense. Other underwriting and operating expenses decreased in 2024 driven by the change in the allowance for expected credit losses.

Underwriting Expense Ratio (the Expense Ratio)

The underwriting expense ratio included the impact of the following:

Year Ended December 31
20242023Change
Underwriting expense ratio, as reported34.3%33.2%1.1pts
Less: impact of audit premium on expense ratio(2.6%)(2.1%)(0.5pts)
Underwriting expense ratio, excluding the effect of audit premium36.9%35.3%1.6pts

Excluding the effect of audit premium, the underwriting expense ratio increased for the year ended December 31, 2024 as compared to 2023 primarily reflecting the non-renewal of the program that assumed both workers' compensation insurance and medical professional liability insurance, which was subject to a lower ceding commission.

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Segment Results - Corporate

Our Corporate segment includes our investment operations excluding those reported in our Segregated Portfolio Cell Reinsurance segment as discussed in Note 16 of the Notes to Consolidated Financial Statements. In addition, this segment includes corporate expenses, interest expense, U.S. and U.K. income taxes and non-premium revenues generated outside of our insurance entities.

Segment results for the years ended December 31, 2024 and 2023 exclude the change in fair value of contingent consideration and, for the year ended December 31, 2024, transaction-related costs, including the associated income tax benefit, as we do not consider these items in assessing the financial performance of the segment. Transaction-related costs are attributable to actuarial consulting fees paid during the second quarter of 2024 in relation to the final determination of contingent consideration associated with the NORCAL acquisition. We did not incur any transaction-related costs in 2023. Segment results for our Corporate segment were net earnings of $94.7 million and $89.8 million for the years ended December 31, 2024 and 2023, respectively, and included the following:

Year Ended December 31
($ in thousands)20242023Change
Net investment income$140,930$126,130$14,80011.7%
Equity in earnings (loss) of unconsolidated subsidiaries$22,203$6,791$15,412226.9%
Net investment gains (losses)$(7,206)$5,148$(12,354)(240.0%)
Other income (expense)$11,489$8,307$3,18238.3%
Operating expense$40,008$34,007$6,00117.6%
Interest expense$22,342$23,150$(808)(3.5%)
Income tax expense (benefit)$10,401$(545)$10,9462,008.4%

Net Investment Income

Net investment income is primarily derived from the income earned by our fixed maturity securities and also includes dividend income from equity securities, income from our short-term and cash equivalent investments, earnings from other investments and changes in the cash surrender value of BOLI contracts, net of investment fees and expenses.

Net investment income (loss) by investment category was as follows:

Year Ended December 31
($ in thousands)20242023Change
Fixed maturities$131,333$112,270$19,06317.0%
Equities4,7584,6101483.2%
Short-term investments, including Other10,72314,262(3,539)(24.8%)
BOLI2,3162,489(173)(7.0%)
Investment fees and expenses(8,200)(7,501)(699)9.3%
Net investment income$140,930$126,130$14,80011.7%

Fixed Maturities

Income from our fixed maturities increased in 2024 as compared to 2023 driven by higher average book yields as we took advantage of the current interest rate environment as our portfolio matures. Additionally, average investment balances were approximately 1.8% higher for 2024 as compared to 2023.

Average yields for our fixed maturity portfolio were as follows:

Year Ended December 31
20242023
Average income yield3.5%3.1%
Average tax equivalent income yield3.5%3.1%

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Short-term Investments and Other Investments

Short-term investments, which have a maturity at purchase of one year or less are carried at fair value, which approximates their cost basis, and are primarily composed of investments in U.S. treasury obligations, commercial paper, money market funds and a certificate of deposit. Income from our short-term and other investments decreased during 2024 as compared to 2023 primarily due to lower average investment balances and lower yields given the decrease in interest rates.

Investment Fees and Expenses

Investment fees and expenses increased in 2024 as compared to 2023 primarily due to the mix of investment managers as well as an increase in service costs.

Equity in Earnings (Loss) of Unconsolidated Subsidiaries

Equity in earnings (loss) of unconsolidated subsidiaries was comprised as follows:

Year Ended December 31
($ in thousands)20242023Change
All other investments, primarily investment fund LPs/LLCs$21,532$9,196$12,336134.1%
Tax credit partnerships671(2,405)3,076127.9%
Equity in earnings (loss) of unconsolidated subsidiaries$22,203$6,791$15,412226.9%

We hold interests in certain LPs/LLCs that generate earnings from trading portfolios, secured debt, debt securities, multi-strategy funds and private equity investments. The performance of the LPs/LLCs is affected by the volatility of equity and credit markets. For our investments in LPs/LLCs, we record our allocable portion of the partnership operating income or loss as the results of the LPs/LLCs become available, typically following the end of a reporting period. Our investment results from our portfolio of investments in LPs/LLCs increased for 2024 as compared to 2023 primarily due to the performance of certain LPs/LLCs which reflected higher market valuations during the first half of 2024 and the fourth quarter of 2023.

Our tax credit partnership investments are designed to generate returns in the form of tax credits and tax-deductible project operating losses and are comprised of qualified affordable housing project tax credit partnerships and a historic tax credit partnership. We account for our tax credit partnership investments under the equity method and record our allocable portion of the operating losses of the underlying properties based on estimates provided by the partnerships. These tax credit partnership investments are reaching the end of their lifecycle, therefore partnership operating losses and tax benefits associated with these investments have been and are expected to continue to be nominal in amount. However, we may receive distributions from time to time due to the sale of properties, as was the case in 2024. The results from our tax credit partnership investments for the year ended December 31, 2024 also reflected the benefit of a decrease in our estimate of our allocable portion of operating losses of $0.7 million as compared to an increase in this estimate of $1.3 million during 2023. See additional information on our tax credit partnership investments in Note 3 of the Notes to Consolidated Financial Statements.

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Net Investment Gains (Losses)

The following table provides detailed information regarding our net investment gains (losses).

Year Ended December 31
(In thousands)20242023
Total impairment losses
Corporate debt$(2,710)$(2,984)
Asset-backed securities(588)(127)
Portion of impairment losses recognized in other comprehensive income before taxes:
Corporate debt102
Net impairment losses recognized in earnings(3,196)(3,111)
Gross realized gains, available-for-sale fixed maturities1,522875
Gross realized (losses), available-for-sale fixed maturities(4,035)(1,800)
Net realized gains (losses), trading fixed securities34(88)
Net realized gains (losses), equity investments(704)(7)
Net realized gains (losses), other investments(826)(2,417)
Change in unrealized holding gains (losses), trading fixed securities44568
Change in unrealized holding gains (losses), equity investments(1,495)2,495
Change in unrealized holding gains (losses), convertible securities, carried at fair value as a part of other investments8665,774
Other1833,359
Net investment gains (losses)$(7,206)$5,148

For the year ended December 31, 2024, we recognized $3.2 million of credit-related impairment losses in earnings primarily related to four corporate bonds in the real estate sector and a nominal amount of non-credit impairment losses in OCI related to a corporate bond in the consumer sector. For the year ended December 31, 2023, we recognized credit-related impairment losses in earnings of $3.1 million related to a mortgage-backed security and two corporate bonds in the financial sector.

We recognized $7.2 million of net investment losses for the year ended December 31, 2024 driven by net realized losses from the sale of certain available-for-sale fixed maturities and, to a lesser extent, unrealized holding losses resulting from changes in the fair value of our equity investments. We recognized $5.1 million of net investment gains for the year ended December 31, 2023 driven by unrealized holding gains resulting from changes in the fair value of our convertible securities and equity investments and, to a lesser extent, death benefit proceeds from BOLI contracts.

Other Income (Expense)

Corporate other income (expense) for the years ended December 31, 2024 as compared to 2023 was comprised of the following:

Year Ended December 31
($ in thousands)20242023Change
Foreign currency exchange rate gains (losses)(1)$6,731$(2,993)$9,724324.9%
Other4,75811,300(6,542)(57.9%)
Total other income (expense)$11,489$8,307$3,18238.3%
(1) See further information on foreign currency exchange rate movements in the Executive Summary of Operations section under the heading "Revenues."

Excluding foreign currency exchange rate movements, other income decreased for the year ended December 31, 2024 as compared to 2023 driven by proceeds of $6.9 million received in 2023 associated with the sale of our remaining ownership interest in the underwriting and operations entity associated with Syndicate 1729 to unrelated third parties.

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Operating Expenses

Corporate segment operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20242023Change
Operating expenses$45,673$39,747$5,92614.9%
Management fee offset(5,665)(5,740)75(1.3%)
Total$40,008$34,007$6,00117.6%

Operating expenses increased during the year ended December 31, 2024 as compared to 2023 driven by an increase in compensation-related costs, certain software and equipment costs and, to a lesser extent, share-based compensation expenses, partially offset by a decrease in professional fees. The increase in compensation-related costs during 2024 primarily reflected higher amounts accrued for performance-related incentive plans due to the improvement in the related performance metrics. The increase in share-based compensation expenses in 2024 reflected an increase in awards outstanding as compared to 2023. The decrease in professional fees during 2024 primarily reflected a decrease in consulting and temporary personnel fees.

Core domestic operating subsidiaries within our Specialty P&C segment and our Workers' Compensation Insurance segment are charged a management fee by the Corporate segment for services provided to these subsidiaries. The management fee is based on the extent to which services are provided to the subsidiary and the amount of premium written by the subsidiary. Under the arrangement, the expenses associated with such services are reported as expenses of the Corporate segment, and the management fees charged are reported as an offset to Corporate operating expenses. While the terms of the arrangement were generally consistent between 2024 and 2023, fluctuations in the amount of premium written by each subsidiary can result in corresponding variations in the management fee charged to each subsidiary during a particular period.

Interest Expense

Interest expense for the years ended December 31, 2024 and 2023 was comprised as follows:

Year Ended December 31
($ in thousands)20242023Change
Senior Notes due 2023$$11,742$(11,742)nm
Contribution Certificates (including accretion)(1)7,5177,567(50)(0.7%)
Revolving Credit Agreement (including fees and amortization)10,2442,4947,750310.7%
Term Loan (including fees and amortization)9,5081,3928,116583.0%
(Gain)/loss on cash flow hedges reclassified from AOCI(4,927)(45)(4,882)10,848.9%
Interest expense$22,342$23,150$(808)(3.5%)
(1) Includes accretion of approximately $1.8 million and $1.9 million for the years ended December 31, 2024 and 2023, respectively, which is recorded as an increase to interest expense as a result of the difference between the recorded acquisition date fair value and the principal balance of the Contribution Certificates associated with our acquisition of NORCAL.

Interest expense decreased during 2024 as compared to 2023 driven by the change in the fair value of our Interest Rate Swaps, largely offset by the higher effective interest rate on our Revolving Credit Agreement and Term Loan as compared to the effective interest rate of our Senior Notes that matured in November 2023. The Interest Rate Swaps are designated as highly effective cash flow hedges to manage our exposure to interest rate risk due to variability in the base rates on the borrowings under both the Revolving Credit Agreement and Term Loan. The change in the fair value of our Interest Rate Swaps in 2023 reflected our short-term exposure to variability in the base rates on these borrowings from November 15, 2023 until the Interest Rate Swaps were effective on December 29, 2023. See further discussion on our outstanding debt in Note 10 of the Notes to Consolidated Financial Statements and additional information regarding our Interest Rate Swaps is provided in Note 11 of the Notes to Consolidated Financial Statements.

Taxes

Tax expense allocated to our Corporate segment includes U.S. and U.K. tax expense including U.S. tax expense incurred from our corporate membership in Lloyd's of London, if any. The SPCs at Inova Re, one of our Cayman Islands reinsurance subsidiaries, have each made a 953(d) election under the U.S. Internal Revenue Code and are subject to U.S. federal income tax; therefore, tax expense allocated to our Corporate segment also includes tax expense incurred from any SPC at Inova Re in which we have a participation interest of 80% or greater as those SPCs are required to be included in our consolidated tax

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return. Consolidated tax expense (benefit) reflects the tax expense (benefit) of both segments and the tax impact of items excluded from segment reporting, as shown in the table below:

Year Ended December 31
(In thousands)20242023
Corporate segment income tax expense (benefit)$10,401$(545)
Income tax expense (benefit) - transaction-related costs*(67)
Consolidated income tax expense (benefit)$10,334$(545)
*Represents the income tax benefit associated with actuarial consulting fees paid during the second quarter of 2024 in relation to the final determination of contingent consideration associated with the NORCAL acquisition. These costs are not included in a segment as we do not consider these costs in assessing the financial performance of any of our operating or reportable segments. See Note 16 of the Notes to Consolidated Financial Statements for a reconciliation of our segment results to our consolidated results.

Listed below are the primary factors affecting our consolidated effective tax rate for the years ended December 31, 2024 and 2023. The comparability of each factor's impact on our effective tax rate is affected by the consolidated pre-tax income recognized during the year ended December 31, 2024 as compared to the consolidated pre-tax loss recognized in 2023. Factors that have the same directional impact on income tax expense in each period have an opposite impact on our effective tax rate due to the effective tax rate being calculated based upon a pre-tax income during the year ended December 31, 2024 as compared to the pre-tax loss during 2023. These factors include the following:

Year Ended December 31
20242023
($ in thousands)Income tax (benefit) expenseRate ImpactIncome tax (benefit) expenseRate Impact
Computed "expected" tax expense (benefit) at statutory rate$13,24721.0%$(8,221)21.0%
Tax-exempt income(1)(1,062)(1.7%)(1,192)3.0%
Tax credits(32)(0.1%)(631)1.6%
Non-U.S. operating results3960.6%(625)1.7%
Tax deficiency (excess tax benefit) on share-based compensation7081.1%191(0.5%)
Non-taxable contingent consideration(2)(1,415)(2.2%)(1,785)4.6%
Goodwill impairment(3)%9,263(23.7%)
Provision-to-return and other differences(42)(0.1%)327(0.8%)
Change in uncertain tax positions(4)(3,004)(4.8%)1,546(3.9%)
Change in limitation of future deductibility of certain executive compensation(198)(0.3%)932(2.4%)
GILTI and subpart F income2920.5%396(1.0%)
State income taxes9111.4%65(0.2%)
Non-taxable gain from life insurance proceeds(42)(0.1%)(682)1.7%
Other5751.1%(129)0.3%
Total income tax expense (benefit)$10,33416.4%$(545)1.4%

(1) Includes tax-exempt interest, dividends received deduction and change in cash surrender value of BOLI.

(2) Represents the tax impact of a decrease in the contingent consideration liability issued in connection with the NORCAL acquisition of $6.5 million and the reversal of a nominal amount of associated contingent investment banker fees accrued during purchase accounting for the year ended December 31, 2024 as compared to a decrease in the contingent consideration liability of $8.5 million for the year ended December 31, 2023, all of which is non-taxable. See further discussion on the contingent consideration in Note 2 and Note 8 of the Notes to Consolidated Financial Statements.

(3) Represents the tax impact of the impairment of non-deductible goodwill in relation to the Workers' Compensation Insurance reporting unit during the third quarter of 2023. See further discussion on the impairment charge in Note 6 of the Notes to Consolidated Financial Statements.

(4) Represents the benefit for tax positions whose statute of limitations has expired.

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FY 2023 10-K MD&A

SEC filing source: 0001875246-24-000009.

Extracted structurally from real Item 7 body heading to real Item 7A/8 boundary. Confidence: high. Filing date: 2024-02-27. Report date: 2023-12-31.

ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

The following discussion generally focuses on the change in financial condition, results of operations and cash flows for the year ended December 31, 2023 as compared to the year ended December 31, 2022 and should be read in conjunction with the Consolidated Financial Statements and Notes to those statements which accompany this report. For a full discussion of the changes in the financial condition, results of operations and cash flows for the year ended December 31, 2022 as compared to the year ended December 31, 2021, please refer to Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" section of ProAssurance's December 31, 2022 report on Form 10-K. Any significant retrospective revisions in the presentation of the changes in the financial condition, results of operations and cash flows for the year ended December 31, 2022 as compared to the year ended December 31, 2021 as reported in ProAssurance's December 31, 2022 report on Form 10-K are located in this report under the section that follows titled "Results of Operations - Year Ended December 31, 2022 Compared to Year Ended December 31, 2021."

Throughout the discussion we use certain terms and abbreviations, which can be found in the Glossary of Terms and Acronyms at the beginning of this report. In addition, a glossary of insurance terms and phrases is available on the investor section of our website. Throughout the discussion, references to "ProAssurance," "PRA," "Company," "organization," "we," "us" and "our" refer to ProAssurance Corporation and its consolidated subsidiaries. The discussion contains certain forward-looking information that involves significant risks, assumptions and uncertainties. As discussed under the heading "Caution Regarding Forward-Looking Statements," our actual financial condition and results of operations could differ significantly from these forward-looking statements.

ProAssurance Overview

ProAssurance Corporation is a holding company for property and casualty insurance companies. Our insurance subsidiaries provide professional liability insurance, liability insurance for medical technology and life sciences risks and workers' compensation insurance.

We have also provided capital to Syndicate 1729 at Lloyd's of London to support our previous participation in underwriting years that remain open. Effective September 2023, we elected to discontinue our participation in the results of Syndicate 1729 beginning with the 2024 underwriting year. The results from our participation in Syndicate 1729 from open underwriting years prior to 2024 will continue to earn out pro rata over the entire policy period of the underlying business. Due to the quarter lag, our ceased participation in Syndicate 1729 will begin to be reflected in our results in the second quarter of 2024. Furthermore, we received proceeds of $6.8 million during 2023 associated with the sale of our remaining ownership interest in the underwriting and operations entity associated with Syndicate 1729 to unrelated third parties.

Our operating segments are based on our internal management reporting structure for which financial results are regularly evaluated by our CODM to determine resource allocation and assess operating performance. As a result of our decision to no longer participate in the results of Syndicate 1729 beginning with the 2024 underwriting year, we reorganized our segment reporting during the third quarter of 2023 to align with how our CODM currently oversees the business, allocates resources and evaluates operating performance and, as a result, the number of our operating and reportable segments decreased from five to four: Specialty P&C, Workers' Compensation Insurance, Segregated Portfolio Cell Reinsurance and Corporate. As a result of the segment reorganization, we now report the underwriting results from our participation in Lloyd’s Syndicates in the Specialty P&C segment and the investment results of assets solely allocated to our Lloyd's Syndicate operations and U.K. income taxes in our Corporate segment. All prior period segment information has been recast to conform to the current period presentation and the segment reorganization had no impact on previously reported consolidated financial results.

Additional information on ProAssurance's four operating and reportable segments is included in Note 16 of the Notes to Consolidated Financial Statements, Part I and in the Segment Results sections herein that follow.

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Growth Opportunities and Outlook

Over the long-term we expect our growth to come primarily through controlled expansion of our existing operations. In addition, we may identify opportunities for growth through the acquisition of other insurers, service providers or books of business.

We operate in very competitive markets and face strong competition from other insurance companies for all of our insurance products. Our Specialty P&C segment includes our HCPL insurance which represents the largest product line in our consolidated gross premiums written (59% in 2023). The Specialty P&C segment also includes our Small Business Unit (9% in 2023), Medical Technology Liability (4% in 2023) and Lloyd's Syndicates (2% in 2023) lines of business. The healthcare market in the U.S. is continuing to consolidate, which brings competitive challenges and opportunities. This consolidation initially took the form of hospitals acquiring physician practices and later the growth of physician groups owned by outside investors. As these trends continue, most physicians no longer practice medicine as owners of an independent practice. Large single and multi-specialty practices often operate in many states. Healthcare delivery settings are changing with the growth of retail delivery by allied healthcare professionals as well as physicians practicing in distributed clinics, pharmacies, large consumer stores and online. These larger commercial enterprises have differing risk management needs from those in the traditional small physician practices. As such, we have enhanced our coverage offerings to fit the needs of combined hospital/physician entities, multi-state medical groups, telemedicine companies, miscellaneous facilities, allied healthcare professionals and self-insured entities even as we continue to service that portion of the market maintaining more traditional practice structures. Our Medical Technology Liability and Small Business Unit lines of business are less affected by these consolidation trends.

In 2024, we plan to restructure the Small Business Unit line of business within our Specialty P&C segment and focus on the automation of specific products. Our goal in 2024 is to develop a fully automated platform initially focused on allied healthcare, advanced practice clinicians and dental professional liability coverages. To achieve this goal, we plan to move the podiatric, chiropractic, and dental coverages from the Small Business Unit into HCPL, forming a new unit called Medical Professional Liability. By combining these resources, ProAssurance will have a single unit dedicated to all of its healthcare insurance specialty areas and be able to meet customer needs more efficiently and effectively in order to better serve this market.

Our operations at Eastern, a provider of workers' compensation insurance, represents the second largest product line in our consolidated gross premiums written (23% in 2023, including alternative market premiums). The workers’ compensation market is highly competitive in our operating territories and multi-line insurers continue to leverage workers’ compensation in their product offerings. Additionally, the rates we charge our policyholders remain pressured by the continuation of loss cost decreases in the states within our operating territories, and most states in which we operate have approved additional loss cost decreases for 2024. Despite the competitive workers' compensation market conditions new business writings increased, while renewal retention remained strong. We believe our workers' compensation product offerings allow us to provide flexibility in offering solutions to our customers at a competitive price.

We believe our emphasis on the fair treatment of our insureds and other important stakeholders through our commitment to “Treated Fairly” has enhanced our market position and differentiated us from other insurers. We will continue to uphold our values of integrity, leadership, relationships and enthusiasm in all of our activities. We will honor these values in the execution of “Treated Fairly” to perform our Mission and realize our Vision. We believe that as we reach more customers with this message we will continue to improve retention and add new insureds.

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Key Performance Measures

We are committed to disciplined underwriting, pricing and loss reserving practices as well as an effective investment strategy, even during difficult market conditions. We are also committed to maintaining prudent operating and financial leverage. We recognize the importance that our customers and producers place on the financial strength of our insurance subsidiaries, and we manage our business to protect our financial security.

In evaluating our performance, we consider a number of performance measures, including the following:

•The net loss ratio which is calculated as net losses and loss adjustment expenses incurred divided by net premiums earned and is a component of underwriting profitability.

•The underwriting expense ratio which is calculated as underwriting, policy acquisition and operating expenses incurred divided by net premiums earned and is a component of underwriting profitability.

•The combined ratio which is the sum of the net loss ratio and the underwriting expense ratio and measures underwriting profitability.

•The investment income ratio which is calculated as net investment income divided by net premiums earned and measures the contribution investment earnings provide to our overall profitability.

•The operating ratio which is the combined ratio, less the investment income ratio. This ratio provides the combined effect of underwriting profitability and investment income.

•The effective tax rate which is calculated as total income tax expense (benefit) divided by income (loss) before income taxes.

•Non-GAAP operating income (loss) which is widely used to evaluate performance within the insurance sector. In calculating Non-GAAP operating income (loss), we exclude the effects of items that do not reflect normal operating results. We believe Non-GAAP operating income (loss) presents a useful view of the performance of our insurance operations; however, it should be considered in conjunction with net income (loss) computed in accordance with GAAP. See a reconciliation to its GAAP counterpart in the Executive Summary of Operations section under the heading “Non-GAAP Financial Measures” that follows.

•ROE which is calculated as net income (loss) divided by the average of beginning and ending shareholders’ equity. This ratio measures our overall after-tax profitability and shows how efficiently capital is being used.

•Non-GAAP operating ROE which is calculated as Non-GAAP operating income (loss) for the period divided by the average of beginning and ending total GAAP shareholders’ equity. Non-GAAP operating ROE measures the overall after-tax profitability of our insurance operations and shows how efficiently capital is being used; however, it should be considered in conjunction with ROE computed in accordance with GAAP. See a reconciliation to its GAAP counterpart in the Executive Summary of Operations section under the heading “Non-GAAP Financial Measures” that follows.

•Book value per share which is calculated as total shareholders’ equity divided by the total number of common shares outstanding at the balance sheet date. This ratio measures the net worth of the Company to shareholders on a per-share basis. The declaration of dividends decreases book value per share. Growth in book value per share, adjusted for dividends declared, is an indicator of overall profitability.

•Non-GAAP adjusted book value per share which is a Non-GAAP measure widely used within the insurance sector and is calculated as shareholders’ equity, excluding AOCI, divided by the total number of common shares outstanding at the balance sheet date. This Non-GAAP calculation measures the net worth of the Company to shareholders on a per share basis excluding AOCI to eliminate the temporary and potentially significant effects of fluctuations in interest rates on our fixed income portfolio; however, it should be considered in conjunction with book value per share computed in accordance with GAAP. See a reconciliation to its GAAP counterpart in the Executive Summary of Operations section under the heading “Non-GAAP Financial Measures” that follows.

In particular, we focus on our combined ratio and investment returns, both of which directly affect our ROE and growth in our book value per share. Currently, we target a dynamic long-term ROE of 700 basis points above the 10-year U.S. Treasury rate, which at December 31, 2023 was approximately 10.9%.

To achieve our long-term ROE target, we emphasize rate adequacy, selective underwriting, effective claims management, operational efficiency gained by leveraging our enhanced scope and scale and prudent investment management. We closely monitor premium revenues, losses and loss adjustment expenses, and underwriting and policy acquisition expenses. Our overall investment strategy is to focus on maximizing current income from our investment portfolio while maintaining appropriate credit risk, liquidity, duration, portfolio diversification and capital efficiency. While we engage in activities that generate other income, these activities, such as insurance agency services, do not constitute a significant use of our resources or a significant source of revenues or profits.

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Critical Accounting Estimates

Our Consolidated Financial Statements are prepared in conformity with GAAP. Preparation of these financial statements requires us to make estimates and assumptions that affect the amounts we report on those statements. We evaluate these estimates and assumptions on an ongoing basis based on current and historical developments, market conditions, industry trends and other information that we believe to be reasonable under the circumstances. We can make no assurance that actual results will conform to our estimates and assumptions; reported results of operations may be materially affected by changes in these estimates and assumptions.

Management considers the following accounting estimates to be critical because they involve significant judgment by management and those judgments could result in a material effect on our financial statements.

Reserve for Losses and Loss Adjustment Expenses

The largest component of our liabilities is our reserve for losses and loss adjustment expenses ("reserve for losses" or "reserve"), and the largest component of expense for our operations is incurred losses and loss adjustment expenses (also referred to as “losses and loss adjustment expenses,” “incurred losses,” “losses incurred” and “losses”). Incurred losses reported in any period reflect our estimate of losses incurred related to the premiums earned in that period as well as any changes to our previous estimate of the reserve required for prior periods.

As of December 31, 2023, our reserve is comprised almost entirely of long-tail exposures. The estimation of long-tailed losses is inherently complex and is subject to significant judgment on the part of management. Due to the nature of our claims, our loss costs, even for claims with similar characteristics, can vary significantly depending upon many factors, including but not limited to the specific characteristics of the claim and the manner or jurisdiction in which the claim is resolved. Long-tailed insurance is characterized by the extended period of time typically required both to assess the viability of a claim and potential damages, if any, and to reach a resolution of the claim. The claims resolution process may extend to more than five years. Further, the industry has experienced new conditions, including changes in settlement trends as a result of COVID-19 due to the effect of the postponement of court cases during the pandemic. The combination of continually changing conditions and the extended time required for claim resolution results in a loss cost estimation process that requires actuarial skill and the application of significant judgment, and such estimates require periodic modification.

Our reserve is established by management after taking into consideration a variety of factors including premium rates, historical paid and incurred loss development trends and our evaluation of the current loss environment including frequency, severity, expected effects of inflation (monetary, social and medical), general economic and social trends, and the legal and political environment. The effect of COVID-19 on recent historical trends regarding timing and severity of claims may also impact certain of these factors and our ultimate estimation of losses. We also take into consideration the conclusions reached by our internal and consulting actuaries. We update and review the data underlying the estimation of our reserve for losses each reporting period and make adjustments to loss estimation assumptions that we believe best reflect emerging data. Both our internal and consulting actuaries perform an in-depth review of our reserve for losses on at least a semi-annual basis using the loss and exposure data of our insurance subsidiaries.

We partition our reserves by accident year, which is the year in which the claim becomes our liability. For claims-made policies, the insured event generally becomes a liability when the event is first reported to us. For occurrence policies, the insured event becomes a liability when the event takes place. For retroactive coverages, the insured event becomes a liability at inception of the underlying contract. As claims are incurred (reported) and claim payments are made, they are aggregated by accident year for analysis purposes. We also partition our reserves by reserve type: case reserves and IBNR reserves. Case reserves are established by our claims departments based upon the particular circumstances of each reported claim and represent our estimate of the future loss costs (often referred to as expected losses) that will be paid on reported claims. Case reserves are decremented as claim payments are made and are periodically adjusted upward or downward as estimates regarding the amount of future losses are revised; reported loss for an individual claim is the case reserve at any point in time plus the claim payments that have been made to date. IBNR reserves are estimated by accident year by our actuarial department and represent our estimate in the aggregate of future development on losses that have been reported to us and our estimate of losses that have been incurred but not reported to us.

Our reserving process can be broadly grouped into three areas: the establishment of the reserve for the current accident year (the initial reserve), the re-estimation of the reserve for prior accident years (development of prior accident years) and the establishment of the initial reserve for risks assumed in business combinations, applicable only in periods in which acquisitions occur (the acquired reserve). A summary of the activity in our net reserve for losses during 2023 and 2022 is provided under the heading "Losses" in the Liquidity and Capital Resources and Financial Condition section that follows.

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Current Accident Year - Initial Reserve

Considerable judgment is required in establishing our initial reserve for any current accident year period, as there is limited data available upon which to base our estimate (see further discussion that follows under the heading "Use of Judgment"). Our process for setting an initial reserve considers the unique characteristics of each product, but in general we rely heavily on the loss assumptions that were used to price business, as our pricing reflects our analysis of loss costs that we expect to incur relative to the insurance product being priced.

Specialty P&C Segment. Loss costs within this segment are impacted by many factors including but not limited to the nature of the claim, including whether or not the claim is an individual or a mass tort claim, the personal situation of the claimant or the claimant's family, the outcome of jury trials, the legislative and judicial climate where any potential litigation may occur, general economic and social trends and the trend of healthcare costs. Within our Specialty P&C segment, for our professional liability business (87% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2023; predominately comprised of our HCPL products), we set an initial reserve using a loss ratio approach based upon our evaluation of the current loss environment including frequency, severity, monetary inflation, social inflation and legal trends. See further discussion in our Segment Results - Specialty Property & Casualty section that follows under the heading "Losses and Loss Adjustment Expenses."

The risks insured in our Medical Technology Liability business (3% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2023) are more varied, and policies are individually priced based on the risk characteristics of the policy and the account. The insured risks range from startup operations to large multinational entities, and the larger entities often have significant deductibles or self-insured retentions. Reserves are established using our most recently developed actuarial estimates of losses expected to be incurred based on factors which include results from prior analysis of similar business, industry indications, observed trends and judgment. Claims in this line of business primarily involve bodily injury to individuals and are affected by factors similar to those of our HCPL line of business. For the Medical Technology Liability business, we also establish an initial reserve using a loss ratio approach, including a provision in consideration of historical loss volatility that this line of business has exhibited.

Workers' Compensation Insurance Segment. Many factors affect the ultimate losses incurred for our workers' compensation coverages (6% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2023) including but not limited to the type and severity of the injury, the age, health and occupation of the injured worker, the estimated length of disability, medical treatment and related costs, and the jurisdiction and workers' compensation laws of the state of the injury occurrence.

We use various actuarial methodologies in developing our workers’ compensation reserve, combined with a review of the payroll exposure base. For the current accident year, given the lack of seasoned information, the different actuarial methodologies produce results with significant variability; therefore, more emphasis is placed on supplementing results from the actuarial methodologies with trends in exposure base, medical expense inflation, general inflation, severity, and claim counts, among other things, to select an ultimate loss indication.

Segregated Portfolio Cell Reinsurance Segment. The factors that affect the ultimate losses incurred for the workers' compensation and HCPL coverages assumed by the SPCs at Inova Re and Eastern Re (2% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2023) are consistent with that of our Workers’ Compensation Insurance and Specialty P&C segments, respectively.

Development of Prior Accident Years

In addition to setting the initial reserve for the current accident year, we reassess the amount of reserve required for prior accident years each period.

The foundation of our reserve re-estimation process is an actuarial analysis that is performed by both our internal and consulting actuaries. This detailed analysis projects ultimate losses based on partitions which include line of business, geography, coverage layer and accident year. The procedure uses the most representative data for each partition, capturing its unique patterns of development and trends. We believe that the use of consulting actuaries provides an independent view of our loss data as well as a broader perspective on industry loss trends.

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The analyses performed by the consulting actuaries analyzes each partition of our business in a variety of ways and uses multiple actuarial methodologies in performing these analyses, including:

•Bornhuetter-Ferguson (Paid and Reported) Method

•Paid Development Method

•Reported (Incurred) Development Method

•Average Paid Value Method

•Average Reported Value Method

A brief description of each method follows.

Bornhuetter-Ferguson Method. We use both the Paid and the Reported Bornhuetter-Ferguson Methods. The Paid Method assigns partial weight to initial expected losses for each accident year (initial expected losses being the first established case and IBNR reserves for a specific accident year) and partial weight to paid to date losses. The Reported Method assigns partial weight to the initial expected losses and partial weight to current reported losses. The weights assigned to the initial expected losses decrease as the accident year matures.

Paid Development and Reported (Incurred) Development Methods. These methods use historical, cumulative losses (paid losses for the Paid Development Method, reported losses for the Reported (Incurred) Development Method) by accident year and develop those actual losses to estimated ultimate losses based upon the assumption that each accident year will develop to estimated ultimate cost in a manner that is analogous to prior years, adjusted as deemed appropriate for the expected effects of known changes in the claim payment environment (and case reserving environment for the Reported (Incurred) Development Method); and to the extent necessary, supplemented by analyses of the development of broader industry data.

Average Paid Value and Average Reported Value Methods. In these methods, average claim cost data (paid claim cost for the Average Paid Value Method and reported claim cost for the Reported Value Method) is developed to an ultimate average cost level by report year based on historical data. Claim counts are similarly developed to an ultimate count level. The average claim cost (after rounding and adjustment, if necessary, to accommodate report year data that is not considered to be predictive) is then multiplied by the ultimate claim counts by report year to derive ultimate loss and ALAE.

We use various actuarial methods in the process of setting reserves. Each actuarial method generally returns a different value, and for the more recent accident years the variations among the different methodologies can be significant. Generally, methods such as the Bornhuetter-Ferguson Method are used on more recent accident years where we have less data on which to base our analysis. As time progresses and we have an increased amount of data for a given accident year, we begin to give more confidence to the development and average methods, as these methods typically rely more heavily on our own historical data. These methods emphasize different aspects of loss reserve estimation and provide a variety of perspectives for our decisions.

Certain of the methodologies utilized to estimate the ultimate losses for each partition of our reserves consider the actual amounts paid. Paid data is particularly influential when a large portion of known claims have been closed, as is the case for older accident years. In selecting a point estimate for each partition, management considers the extent to which trends are emerging consistently for all partitions and known industry trends. Thus, actual, rather than estimated severity trends are given more consideration. If actual severity trends are lower than those estimated at the time that reserves were previously established, the recognition of favorable development is indicated. This is particularly true for older accident years where our actuarial methodologies give more weight to actual loss costs (severity).

The various actuarial methods discussed above are applied in a consistent manner from period to period. For each partition of our reserves, we evaluate the results of the various methods, along with the supplementary statistical data regarding such factors as closed with and without indemnity ratios, claim severity trends, the expected duration of such trends, changes in the legal and legislative environment and the current economic environment to develop a point estimate based upon management's judgment and past experience. The series of selected point estimates is then combined to produce an overall point estimate for ultimate losses.

We utilize the selected point estimates of ultimate losses to develop estimates of ultimate losses recoverable from reinsurers, based on the terms and conditions of our reinsurance agreements. An overall estimate of the amount receivable from reinsurers is determined by combining the individual estimates. Our net reserve estimate is the gross reserve point estimate less the estimated reinsurance recovery.

For our Workers’ Compensation Insurance segment and for the workers' compensation exposures in our Segregated Portfolio Cell Reinsurance segment, we utilize the Reported (Incurred) Development Method, Paid Development Method and Bornhuetter-Ferguson Method, to develop our reserve for each accident year. The actuarial review includes the stratification of claims data (lost time claims, medical only claims) using different variations that allow us to identify trends that may not be readily identifiable if the data was evaluated only in the aggregate. Reported and paid loss development factors are key assumptions in the reserve estimation process and are based on our historical reported and paid loss development patterns. As accident years mature, the various actuarial methodologies produce more consistent loss estimates.

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Acquired Reserve

The acquisition of NORCAL on May 5, 2021 increased our gross reserves by $1.2 billion which was the fair value of NORCAL's gross loss reserve at the time of acquisition. The fair value estimate of NORCAL's gross reserve for losses and loss adjustment expenses was based on three components: an actuarial estimate of the expected future net cash flows, a reduction to those cash flows for the time value of money determined utilizing the U.S. Treasury Yield Curve and a risk margin adjustment to reflect the net present value of profit that an investor would demand in return for the assumption of the development risk associated with the reserve. The fair value of NORCAL's gross reserve, including the risk margin adjustment, exceeded the actuarial estimate of NORCAL’s undiscounted gross loss reserve by approximately $42.2 million as of May 5, 2021. This fair value adjustment was recorded to the reserve for losses and loss adjustment expenses and will be amortized over a period utilizing loss payment patterns as a reduction to prior accident year net losses and loss adjustment expenses. We also recorded other adjustments to NORCAL’s reserve as a result of purchase accounting including negative VOBA on NORCAL’s assumed unearned premium and assumed DDR reserve.

Use of Judgment/Variability of Loss Reserves

The process of estimating reserves involves a high degree of judgment and is subject to a number of variables. These variables can be affected by both views of internal and external events, such as changes in views of monetary and social inflation, legal trends and legislative changes, as well as differentiating views of individuals involved in the reserve estimation process, among others. We continually refine our estimates in a regular, ongoing process as historical loss experience develops and additional claims are reported and settled. Our objective is to consider all significant facts and circumstances known at the time.

Our loss reserves may be impacted by social inflation, which is generally described as the rising costs of insurance claims resulting from factors including, but not limited to, increasing litigation, broader definitions of liability, more plaintiff-friendly legal decisions, jury behavior, and larger compensatory jury awards and non-economic damages. These factors could lead to greater than anticipated claims and claim handling expenses which could exceed our established reserves causing us to increase our loss reserves.

The effects of monetary and medical inflation could cause the cost of claims to rise in the future. Our loss reserves include assumptions about future payments for settlement of claims and claims handling expenses, such as medical treatments and litigation costs. For our workers' compensation reserves, healthcare wage inflation and medical advancements may also increase the cost of claims. To the extent inflation causes these costs to increase above reserves established for these claims, we will be required to increase our loss reserves with a corresponding reduction in our financial results in the period in which the need for additional reserves is identified.

HCPL. Over the past several years the most influential factor affecting the analysis of our HCPL reserves and the related development recognized has been an observed increase in claim severity for the broader medical professional liability industry as well as higher initial loss expectations on incurred claims. The severity trend is an explicit component of our pricing models and directly impacts the reserving process. Our estimate of this trend and our expectations about changes in this trend impact a variety of factors, from the selection of expected loss ratios to the ultimate point estimates established by management.

Because of the implicit and wide-ranging nature of severity trend assumptions on the loss reserving process, it is not practical to specifically isolate the impact of changing severity trends. However, because severity is an explicit component of our HCPL pricing process we can better isolate the impact that changing severity can have on our loss costs and loss ratios in regards to our pricing models for this business component. Our current HCPL pricing models assume severity trends in the range of 2% to 6% depending on state, territory and specialty. In some portions of our HCPL business we have observed and reflected higher severity trends in our estimates of losses and loss adjustment expenses.

Due to the long-tailed nature of our claims and the previously discussed historical volatility of loss costs, selection of a severity trend assumption is a subjective process that is inherently likely to prove inaccurate over time. Given the long tail and volatility, we are generally cautious in making changes to the severity assumptions within our pricing models. All open claims and accident years are generally impacted by a change in the severity trend, which compounds the effect of such a change.

Although the future degree and impact of the ultimate severity trend remains uncertain due to the long-tailed nature of our business, we have given consideration to observed loss costs in setting our rates. For our HCPL business, this practice has recently resulted in rate increases reflecting the rising loss cost environment, and we anticipate further renewal pricing increases due to increasing loss severity.

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Workers' Compensation. In our workers’ compensation business, severity is not an explicit component of our pricing process, as loss costs are established by the states in which we operate. We do, however, have the ability in certain states to apply for increases in our loss cost multipliers to adjust for company specific loss experience that is higher than state loss cost changes. In our reserving process, we consider the loss severity trends in evaluating both our current and expected loss development. Historically, we have been able to minimize the impact of higher severity trends as a result of our early intervention and case management strategies in our claims process, which results in claims being resolved more quickly than the industry norm. However, in the second half of 2023, we observed higher than expected loss trends in our average cost per claim which we primarily attribute to increased medical costs driven by wage inflation and medical advancements. In response to these trends, we increased both our current accident year loss ratio and prior year reserves in 2023. Given our shorter tail, we believe we are recognizing these trends earlier than the overall industry.

As previously noted, the number of data points and variables considered and the subjective process followed in establishing our loss reserve makes it impractical to isolate individual variables and demonstrate their impact on our estimate of loss reserves. However, to provide a better understanding of the potential variability in our reserves, we have modeled implied reserve ranges around our single point net reserve estimates for our various lines of business assuming different confidence levels. The ranges have been developed by aggregating the expected volatility of losses across partitions of our business to obtain a consolidated distribution of potential reserve outcomes. The aggregation of this data takes into consideration correlations among our geographic and specialty mix of business. The result of the correlation approach to aggregation is that the ranges are narrower than the sum of the ranges determined for each partition.

We have used this modeled statistical distribution to calculate an 80% and 60% confidence interval for the potential outcome of our consolidated net reserve for losses. The high and low end points of the distributions are as follows:

Low End PointCarried Net ReserveHigh End Point
80% Confidence Level$2.205 billion$2.956 billion$3.837 billion
60% Confidence Level$2.409 billion$2.956 billion$3.449 billion

Any change in our estimate of net ultimate losses for prior years is reflected in net income (loss) in the period in which such changes are made. Due to the size of our consolidated reserve for losses and the large number of claims outstanding at any point in time, even a small percentage adjustment to our total reserve estimate could have a material effect on our results of operations for the period in which the adjustment is made, as was the case in 2023, 2022 and 2021.

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Loss Development by Line of Business

Professional Liability

Our professional liability line of business includes both our HCPL and Small Business Unit lines, with our HCPL line representing the largest component of our reserve. As a result of the higher severity environment, we saw our closed-with-indemnity-payment ratio (i.e., the number of suits closed with an indemnity or loss payment as compared to the total number of closed suits) for our claims increase from 28% in 2015 to 35% in 2023.

The following table presents additional information about the loss development for our professional liability line of business, excluding loss development for HCPL coverages assumed by the SPCs at Inova Re and Eastern Re. Furthermore, loss development for our professional liability line of business for the years ended December 31, 2023, 2022 and 2021 excludes the amortization of purchase accounting fair value adjustments:

($ in thousands)202320222021
Accident YearsEstimated Ultimate Losses, Net of Reinsurance, December 31, 2023Reserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims Closed
2023$601,021N/A24.7%N/AN/AN/AN/A
2022$612,022$(10,151)55.0%N/A26.9%N/AN/A
2021$727,311$(11,690)71.6%$(5,754)52.9%N/A25.9%
2020$882,943$44,06182.5%$(17,597)66.7%$(4,947)54.1%
2019$879,115$5,22090.4%$20,28583.5%$(20,426)73.7%
2018$849,896$41393.6%$4,49189.5%$9,41881.0%
2017$716,101$(8,265)95.4%$(10,261)93.3%$(2,342)88.4%
2016$738,512$(2,922)92.3%$1,64291.0%$(2,739)89.5%
2015$669,084$(3,825)98.9%$5,19098.1%$6,01197.1%
2014$614,713$(3,730)99.4%$(1,266)99.0%$(1,017)98.5%
Prior to 2014$9,601,765$498$(10,731)$(870)

•The loss environment in our HCPL line of business continues to be challenging in some jurisdictions, as claim costs are pressured by social inflation and higher than anticipated loss severity trends which started to emerge in the fourth quarter of 2022. We are monitoring the impact that these trends have on our open case reserves and prior year development. Net unfavorable reserve development in 2023 principally related to accident years 2019 and 2020. Net unfavorable reserve development recognized in 2023 was driven by the strengthening of case reserves related to four large claims resulting in unfavorable development of $10.1 million in our HCPL line of business during the first quarter of 2023 and unfavorable development associated with our Small Business Unit. Further, we recognized unfavorable development in the fourth quarter of 2023 in NORCAL’s 2020 and prior accident year reserves which was entirely offset by favorable development recognized in NORCAL’s 2021 and 2022 accident year reserves since acquisition. These adjustments to NORCAL’s reserves had no impact to the segment’s net losses.

•Development recognized during 2022 principally related to accident years 2017, 2020 and 2021. Net favorable development recognized in 2022 included favorable development related to NORCAL's 2021 accident year. Net favorable prior accident year reserve development recognized in 2022 was partially offset by unfavorable development recognized in our HCPL line of business, excluding NORCAL, driven by higher than anticipated loss severity trends, which emerged primarily in the fourth quarter of 2022. In addition, we recognized favorable prior year reserve development of $9.0 million in 2022 related to the 2020 accident year associated with the remaining reduction to our previous COVID-19 IBNR reserve due to the fact that early first notices of potential claims did not turn into claims.

•Development recognized during 2021 principally related to accident years 2016 through 2020. We also recognized favorable prior year reserve development of $1.0 million associated with the reduction to our previous COVID-19 IBNR reserve.

•Not included in the table above, is $8.3 million, $10.8 million and $7.9 million of amortization of the purchase accounting fair value adjustment on NORCAL's assumed net reserve and amortization of the negative VOBA associated with NORCAL's DDR reserve which is recorded as a reduction to prior accident year net losses and loss adjustment expenses in 2023, 2022 and 2021, respectively.

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•Not included in the above table, as previously discussed, is $1.3 million and $0.7 million of unfavorable development recognized in 2023 and 2022, respectively, and $2.5 million of favorable development recognized during 2021 in our Segregated Portfolio Cell Reinsurance segment related to the HCPL coverages assumed by the SPCs at Inova Re and Eastern Re.

Medical Technology Liability

Our Medical Technology Liability line of business has not experienced the change in claims frequency previously described for HCPL. However, the nature of the risks insured and volatility of the loss experience in this line of business has produced more variable loss development, as presented in the following table:

($ in thousands)202320222021
Accident YearsEstimated Ultimate Losses, Net of Reinsurance, December 31, 2023Reserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims Closed
2023$18,864N/A28.0%N/AN/AN/AN/A
2022$16,235$(1,448)59.6%N/A16.8%N/AN/A
2021$12,498$(1,647)73.0%$(2,759)53.3%N/A32.0%
2020$11,126$(1,442)80.1%$(1,921)70.6%$(248)59.2%
2019$13,481$1,23561.3%$(1,337)55.3%$72247.5%
2018$9,053$49989.5%$(252)86.4%$(3,091)85.1%
2017$6,911$(1,056)99.0%$1,95097.1%$(2,192)94.1%
2016$8,629$(517)99.5%$53598.4%$(2,126)97.3%
2015$7,919$70399.4%$(767)97.6%$(638)97.0%
2014$7,828$(1,302)100.0%$(244)99.6%$(317)99.6%
Prior to 2014$598,875$976$(205)$(234)

•Approximately $4.5 million of the $4.0 million total net favorable development recognized in 2023 related to the 2020 through 2022 accident years. The development for the 2020 through 2022 accident years represents a 10.2% reduction to the ultimates established for those reserves at December 31, 2022.

•Approximately $6.3 million of the $5.0 million total net favorable development recognized in 2022 related to the 2018 through 2021 accident years. The development for the 2018 through 2021 accident years represents a 11.7% reduction to the ultimates established for those reserves at December 31, 2021.

•Approximately $7.6 million of the $8.1 million total net favorable development recognized in 2021 related to the 2015 through 2020 accident years. The development for the 2015 through 2020 accident years represents a 11.3% reduction to the ultimates established for those reserves at December 31, 2020.

•In 2023, 2022 and 2021 the development was largely attributable to favorable results from claims closed during the year. As time has elapsed we have recognized that actual loss experience has on average been better than estimated. We have been cautious in recognizing the improvement, but as claims have matured and claims are closed or have become more certain for the remaining open claims, we have revised reserve estimates. We believe the need for a cautious approach is required as outcomes are uncertain and results can be significantly affected by outcomes for a small number of cases.

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Workers' Compensation

Claims in our workers’ compensation line of business have historically closed at a faster rate than in our HCPL or Medical Technology Liability lines of business. This faster disposition rate, along with a lower net retention after the application of reinsurance, has resulted in less volatility in loss estimates on a net basis. However, a change in the number of individually-severe claims can create volatility in a given accident year. The following table presents additional information about the loss development for our workers' compensation line of business:

($ in thousands)202320222021
Accident YearsEstimated Ultimate Losses, Net of Reinsurance, December 31, 2023Reserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims Closed
2023$149,175N/A40.3%N/AN/AN/AN/A
2022$151,669$9,01681.3%N/A39.8%N/AN/A
2021$147,124$1,21792.8%$67582.6%N/A45.4%
2020$135,410$(2,318)96.7%$(3,348)93.8%$(1,493)85.1%
2019$147,904$(2,119)97.9%$(4,143)96.2%$(4,030)92.1%
2018$157,333$(1,819)98.1%$(410)97.2%$(1,503)95.2%
2017$125,614$(711)98.7%$(3,209)98.2%$(2,375)97.3%
2016$107,375$(231)99.0%$(2,179)98.5%$(1,230)97.8%
2015$116,045$(232)99.2%$(1,285)98.9%$(1,538)98.4%
2014$117,046$4599.5%$(891)99.4%$(873)99.3%
Prior to 2014$772,393$1,166$(216)$(1,678)

•In 2023, we recognized $9.3 million of net unfavorable development in our Workers' Compensation Insurance segment and $5.3 million of net favorable development in our Segregated Portfolio Cell Reinsurance segment related to workers' compensation business. The net unfavorable prior year reserve development in 2023 reflects higher than expected average claim costs primarily in the 2022 accident year and higher than expected loss experience primarily attributable to a large claim from the 1997 accident year.

•In 2022, we recognized $7.0 million of net favorable development in our Segregated Portfolio Cell Reinsurance segment related to workers' compensation business and $8.0 million of net favorable development in our Workers' Compensation Insurance segment.

•In 2021, we recognized $7.6 million of net favorable development in our Segregated Portfolio Cell Reinsurance segment related to workers' compensation business, and $7.1 million of net favorable development in our Workers' Compensation Insurance segment.

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Reinsurance

We use insurance and reinsurance (collectively, “reinsurance”) to provide capacity to write larger limits of liability, to provide reimbursement for losses incurred under the higher limit coverages we offer, to provide protection against losses in excess of policy limits and, in the case of risk sharing arrangements, to align our objectives with those of our strategic business partners and to provide custom insurance solutions for large customer groups. The purchase of reinsurance does not relieve us from the ultimate risk on our policies; however, it does provide reimbursement for certain losses we pay.

We make a determination of the amount of insurance risk we choose to retain based upon numerous factors, including our risk tolerance and the capital we have to support it, the price and availability of reinsurance, the volume of business, our level of experience with a particular set of exposures and our analysis of the potential underwriting results. We purchase excess of loss reinsurance to limit the amount of risk we retain and we do so from a number of companies to mitigate concentrations of credit risk. As of December 31, 2023, there is no reinsurer, on an individual basis, for which our recoverables for both paid and unpaid claims (net of amounts due to the reinsurer) and our prepaid balances are more than $65 million, in the aggregate. We utilize reinsurance brokers to assist us in the placement of these reinsurance programs and in the analysis of the credit quality of our reinsurers. The determination of which reinsurers we choose to do business with is based upon an evaluation of their then current financial strength, rating, stability and claims payment practices.

We evaluate each of our ceded reinsurance contracts at inception to confirm that there is sufficient risk transfer to allow the contract to be accounted for as reinsurance under current accounting guidance. At December 31, 2023, all ceded contracts were accounted for as risk transferring contracts.

Our receivable from reinsurers on unpaid losses and loss adjustment expenses represents our estimate of the amount of our reserve for losses that will be recoverable under our reinsurance programs. We base our estimate of funds recoverable upon our expectation of ultimate losses and the portion of those losses that we estimate to be allocable to reinsurers based upon the terms and conditions of our reinsurance agreements. Our assessment of the collectability of the recorded amounts receivable from reinsurers considers the payment history of the reinsurer, publicly available financial and rating agency data, our interpretation of the underlying contracts and policies and responses by reinsurers.

Given the uncertainty inherent in our estimates of losses and related amounts recoverable from reinsurers, these estimates may vary significantly from the ultimate outcome.

Under the terms of certain of our reinsurance agreements, the amount of premium that we cede to our reinsurers is based in part on the losses we recover under the agreements. Therefore, we make an estimate of premiums ceded under these reinsurance agreements subject to certain minimums and maximums. Any adjustments to our estimates of losses recoverable under our reinsurance agreements or the premiums owed under our agreements are reflected in current operations. Due to the size of our reinsurance balances, an adjustment to these estimates could have a material effect on our results of operations for the period in which the adjustment is made.

Our reinsurance receivables are exposed to credit losses but to date have not experienced any significant amount of credit losses. To partially mitigate our exposure to credit losses, reinsurance receivables totaling approximately $106.9 million were collateralized by letters of credit or funds withheld as of December 31, 2023. We measure expected credit losses on our reinsurance receivables on a collective basis when similar risk characteristics exist or on an individual basis if we determine a receivable does not share similar risk characteristics. We measure expected credit losses associated with our reinsurance receivables (related to both paid and unpaid losses) at the consolidated level as our reinsurance receivables share similar risk characteristics including type of financial asset, type of industry and similar historical and expected credit loss patterns. We measure expected credit losses over the average contractual term of our reinsurance receivables utilizing a loss rate method. Historical internal credit loss experience is the basis for our assessment of expected credit losses; however, we may also consider historical credit loss information from external sources. We also consider reasonable and supportable forecasts of future economic conditions in our estimate of expected credit losses. Expected credit losses associated with our reinsurance receivables (related to both paid and unpaid losses) were nominal in amount as of December 31, 2023 and 2022. No reinsurance balances were written off for credit reasons during the years ended December 31, 2023 or 2022. Should our expected credit loss analysis or other facts or circumstances lead us to believe that any reinsurer may not meet its obligations to us, adjustments to the allowance for expected credit losses or to reinsurance receivables would be reflected in current operations. Such an adjustment has the potential to be material to the results of operations in the period in which it is recorded; however, we would not expect such an adjustment to have a material effect on our capital position or our liquidity. For further information on our allowance for expected credit losses related to our receivables from reinsurers see Note 1 of the Notes to Consolidated Financial Statements.

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Investment Valuations

We record the majority of our investments at fair value as shown in the table below. At December 31, 2023, the distribution of our investments based on GAAP fair value hierarchies (levels) was as follows:

Distribution by GAAP Fair Value Hierarchy
Level 1Level 2Level 3Not CategorizedTotal Investments
Investments recorded at:
Fair value7%82%2%6%97%
Other valuations3%
Total Investments100%

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. All of our fixed maturity and equity investments are carried at fair value. The fair value of our short-term securities approximates the cost of the securities due to their short-term nature.

Because of the number of securities we own and the complexity of developing accurate fair values, we utilize multiple independent pricing services to assist us in establishing the fair value of individual securities. The pricing services provide fair values based on exchange-traded prices, if available. If an exchange-traded price is not available, the pricing services, if possible, provide a fair value that is based on multiple broker/dealer quotes or that has been developed using pricing models. Pricing models vary by asset class and utilize currently available market data for securities comparable to ours to estimate a fair value for our securities. The pricing services scrutinize market data for consistency with other relevant market information before including the data in the pricing models. The pricing services disclose the types of pricing models used and the inputs used for each asset class. Determining fair values using these pricing models requires the use of judgment to identify appropriate comparable securities and to choose a valuation methodology that is appropriate for the asset class and available data.

The pricing services provide a single value per instrument quoted. We review the values provided for reasonableness each quarter by comparing market yields generated by the supplied value versus market yields observed in the marketplace. We also compare yields indicated by the provided values to appropriate benchmark yields and review for values that are unchanged or that reflect an unanticipated variation as compared to prior period values. We utilize a primary pricing service for each security type and compare provided information for consistency with alternate pricing services, known market data and information from our own trades, considering both values and valuation trends. We also review weekly trades versus the prices supplied by the services. If a supplied value appears unreasonable, we discuss the valuation in question with the pricing service and make adjustments if deemed necessary. Historically our review has not resulted in any material changes to the values supplied by the pricing services. The pricing services do not provide a fair value unless an exchange-traded price or multiple observable inputs are available. As a result, the pricing services may provide a fair value for a security in some periods but not others, depending upon the level of recent market activity for the security or comparable securities.

Level 1 Investments

Fair values for a majority of our equity securities and portions of our short-term and convertible securities are determined using exchange-traded prices. There is little judgment involved when fair value is determined using an exchange-traded price. In accordance with GAAP, we classify securities valued using an exchange-traded price as Level 1 securities.

Level 2 Investments

Most fixed income securities do not trade daily; thus, exchange-traded prices are generally not available for these securities. However, market information (often referred to as observable inputs or market data, including but not limited to, last reported trade, non-binding broker quotes, bids, benchmark yield curves, issuer spreads, two-sided markets, benchmark securities, offers and recent data regarding assumed prepayment speeds, cash flow and loan performance data) is available for most of our fixed income securities. We determine fair value for a large portion of our fixed income securities using available market information. In accordance with GAAP, we classify securities valued based on multiple market observable inputs as Level 2 securities.

Level 3 Investments

When a pricing service does not provide a value for one of our fixed maturity securities, management estimates fair value using either a single non-binding broker quote or pricing models that utilize market based assumptions which have limited observable inputs. The process involves significant judgment in selecting the appropriate data and modeling techniques to use in the valuation process. In accordance with GAAP, we classify securities valued using limited observable inputs as Level 3 securities.

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Fair Values Not Categorized

We hold interests in certain investment funds, primarily LPs/LLCs, which measure fund assets at fair value on a recurring basis and provide us with a NAV for our interest. As a practical expedient, we consider the NAV provided to approximate the fair value of the interest. In accordance with GAAP, we do not categorize these investments within the fair value hierarchy.

Nonrecurring Fair Value Measurements

We measure the fair value of certain assets on a nonrecurring basis when events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. These assets include investments carried principally at cost, investments in tax credit partnerships, fixed assets, goodwill and other intangible assets. These assets would also include any equity method investments that do not provide a NAV. During the third quarter of 2023, we recognized a nonrecurring fair value measurement related to the goodwill in our Workers' Compensation Insurance reporting unit with a carrying value of $44.1 million prior to the fair value measurement. This nonrecurring fair value measurement resulted in the goodwill being written down to its implied fair value of zero resulting in an impairment of goodwill of $44.1 million (see following discussion under the heading "Goodwill / Intangibles"). The inputs used in the fair value measurement were non-observable and, as such, were categorized as a Level 3 valuation. We did not have any other assets or liabilities that were measured at fair value on a nonrecurring basis at December 31, 2023 or December 31, 2022.

Investments - Other Valuation Methodologies

Certain of our investments, in accordance with GAAP for the type of investment, are measured using methodologies other than fair value. At December 31, 2023, these investments represented approximately 3% of total investments, and are detailed in the following table. Additional information about these investments is provided in Note 2 and Note 3 of the Notes to Consolidated Financial Statements.

(In millions)Carrying ValueGAAP Measurement Method
Other investments:
Other, principally FHLB capital stock$3.2Principally Cost
Investment in unconsolidated subsidiaries:
Investments in tax credit partnerships0.7Equity
Equity method investments, primarily LPs/LLCs30.6Equity
31.3
BOLI78.2Cash surrender value
Total investments - Other valuation methodologies$112.7

Impairments

We evaluate our available-for-sale investment securities, which at December 31, 2023 and December 31, 2022 consisted entirely of fixed maturity securities, on at least a quarterly basis for the purpose of determining whether declines in fair value below recorded cost basis represent an impairment loss. We consider a credit-related impairment loss to have occurred:

•if there is intent to sell the security;

•if it is more likely than not that the security will be required to be sold before full recovery of its amortized cost basis; or

•if the entire amortized basis of the security is not expected to be recovered.

The assessment of whether the amortized cost basis of a security is expected to be recovered requires management to make assumptions regarding various matters affecting future cash flows. The choice of assumptions is subjective and requires the use of judgment. Actual credit losses experienced in future periods may differ from management’s current estimates of those credit losses. Methodologies used to estimate the present value of expected cash flows are:

The estimate of expected cash flows is determined by projecting a recovery value and a recovery time frame and assessing whether further principal and interest will be received. We consider various factors in projecting recovery values and recovery time frames, including the following:

•third-party research and credit rating reports;

•the current credit standing of the issuer, including credit rating downgrades, whether before or after the balance sheet date;

•the extent to which the decline in fair value is attributable to credit risk specifically associated with the security or its issuer;

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•internal assessments and the assessments of external portfolio managers regarding specific circumstances surrounding an investment, which indicate the investment is more or less likely to recover its amortized cost than other investments with a similar structure;

•for asset-backed securities, the origination date of the underlying loans, the remaining average life, the probability that credit performance of the underlying loans will deteriorate in the future and our assessment of the quality of the collateral underlying the loan;

•failure of the issuer of the security to make scheduled interest or principal payments;

•any changes to the rating of the security by a rating agency;

•recoveries or additional declines in fair value subsequent to the balance sheet date;

•adverse legal or regulatory events;

•significant deterioration in the market environment that may affect the value of collateral (e.g., decline in real estate prices);

•significant deterioration in economic conditions; and

•disruption in the business model resulting from changes in technology or new entrants to the industry.

If deemed appropriate and necessary, a discounted cash flow analysis is performed to confirm whether a credit loss exists and, if so, the amount of the credit loss. We use the single best estimate approach for available-for-sale debt securities and consider all reasonably available data points, including industry analyses, credit ratings, expected defaults and the remaining payment terms of the debt security. For fixed rate available-for-sale debt securities, cash flows are discounted at the security's effective interest rate implicit in the security at the date of acquisition. If the available-for-sale debt security’s contractual interest rate varies based on subsequent changes in an independent factor, such as an index or rate, for example, the prime rate, the SOFR, or the U.S. Treasury bill weekly average, that security’s effective interest rate is calculated based on the factor as it changes over the life of the security. If we intend to sell a debt security or believe we will more likely than not be required to sell a debt security before the amortized cost basis is recovered, any existing allowance will be written off against the security's amortized cost basis, with any remaining difference between the debt security's amortized cost basis and fair value recognized as an impairment loss in earnings.

Exclusive of securities where there is an intent to sell or where it is not more likely than not that the security will be required to be sold before recovery of its amortized cost basis, impairment for debt securities is separated into a credit component and a non-credit component. The credit component of an impairment is the difference between the security’s amortized cost basis and the present value of its expected future cash flows, while the non-credit component is the remaining difference between the security’s fair value and the present value of expected future cash flows. An allowance for expected credit losses will be recorded for the expected credit losses through income and the non-credit component is recognized in OCI. The amount of impairment recognized is limited to the excess of the amortized cost over the fair value of the available-for-sale debt security.

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Deferred Taxes

Deferred federal income taxes arise from the recognition of temporary differences between the basis of assets and liabilities determined for financial reporting purposes and the basis determined for income tax purposes. Our temporary differences principally relate to our loss reserves, unearned and advanced premiums, DPAC, NOL and tax credit carryforwards, compensation related items, unrealized investment gains (losses) and basis differences on fixed assets, intangible assets and operating leases. Deferred tax assets and liabilities are measured using the enacted tax rates expected to be in effect when such benefits are realized. We review our deferred tax assets quarterly for impairment. If we determine that it is more likely than not that some or all of a deferred tax asset will not be realized, a valuation allowance is recorded to reduce the carrying value of the asset. In assessing the need for a valuation allowance, management is required to make certain judgments and assumptions about our future operations based on historical experience and information as of the measurement period regarding reversal of existing temporary differences, carryback capacity, future taxable income of the appropriate character (including its capital and operating characteristics) and tax planning strategies.

A significant portion of our deferred tax asset is related to unrealized losses on our fixed maturities due to the significant effect of fluctuations in interest rates in 2022 that continued through 2023. Any loss realized prior to recovery would require sufficient income of the appropriate character (i.e., capital gains), and in the appropriate timeframe, to realize the tax benefit. We believe that we have the intent and ability to hold these securities until their recovery. Our projected positive operating income, including the investment income generated from holding our debt securities until maturity, support our ability to implement this tax planning strategy.

A valuation allowance has been established against the deferred tax asset related to the NOL carryforwards for our U.K. operations and against a portion of the deferred tax asset related to our U.S. state NOL carryforwards. In addition, a valuation allowance was established against the net deferred tax asset of ProAssurance American Mutual, A Risk Retention Group. As a taxpayer separate from the consolidated group, this entity has experienced cumulative losses in recent years. Management concluded that it was more likely than not that these deferred tax assets will not be realized. We also established a valuation allowance in a prior year against the deferred tax assets of certain SPCs at our wholly owned Cayman Islands reinsurance subsidiary, Inova Re. Due to the cumulative losses incurred in recent years by these SPCs, management concluded that a valuation allowance was required. As of December 31, 2023, management concluded that the previously recorded valuation allowances were still required against the deferred tax assets related to the NOL carryforwards for our U.K. operations, against the deferred tax assets related to some of our U.S. state NOL carryforwards, the deferred tax assets of certain SPCs at Inova Re and against the net deferred tax asset of ProAssurance American Mutual, A Risk Retention Group. Management’s assessment of the need for these valuation allowances at December 31, 2023 included an analysis of the available sources of income. See further discussion on ProAssurance’s deferred tax assets in Note 5 of the Notes to Consolidated Financial Statements.

U.S. Tax Legislation

Coronavirus Aid, Relief and Economic Security Act

In response to COVID-19, the CARES Act was signed into law on March 27, 2020 and contains several provisions for corporations and eased certain deduction limitations originally imposed by the TCJA. See further discussion in Note 5 of the Notes to Consolidated Financial Statements. Temporary changes regarding NOL carryback provisions included in the CARES Act had a favorable impact on our liquidity, as we were able to carryback our 2019 and 2020 net operating losses to claim refunds (see discussion that follows in the Liquidity and Capital Resources and Financial Condition section under the heading "Taxes"). See further discussion in Note 5 of the Notes to Consolidated Financial Statements.

Unrecognized Tax Benefits

We evaluate tax positions taken on tax returns and recognize positions in our financial statements when it is more likely than not that we will sustain the position upon resolution with a taxing authority. If recognized, the benefit is measured as the largest amount of benefit that has a greater than 50% probability of being realized. We review uncertain tax positions each quarter, considering changes in facts and circumstances, such as changes in tax law, interactions with taxing authorities and developments in case law, and make adjustments as we consider necessary. Adjustments to our unrecognized tax benefits may affect our income tax expense, and settlement of uncertain tax positions may require the use of cash. Other than differences related to timing, no significant adjustments were considered necessary during 2023 or 2022. At December 31, 2023, our liability for unrecognized tax benefits approximated $4.8 million.

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Goodwill / Intangibles

In accordance with GAAP, goodwill and other indefinite lived intangible assets are tested for impairment annually or more frequently if circumstances indicate an impairment may have occurred. The date of our annual impairment testing is October 1. Impairment of goodwill is tested at the reporting unit level, which prior to the third quarter of 2023, was consistent with our reportable segments. As discussed in Note 16 of the Notes to Consolidated Financial Statements, we reorganized our segment reporting in the third quarter of 2023 to align with how our CODM currently oversees the business, allocates resources and evaluates operating performance. As a result of the segment reorganization, the Lloyd's Syndicates segment is no longer a separate operating segment; however, the Lloyd's Syndicates operation will remain a reporting unit for purposes of testing goodwill. Our reporting units are: Specialty P&C, Workers' Compensation Insurance, Segregated Portfolio Cell Reinsurance, Lloyd's Syndicates and Corporate. Of the five reporting units, only the Segregated Portfolio Cell Reinsurance reporting unit has goodwill at December 31, 2023.

During the third quarter of 2023, we recorded a goodwill impairment charge of $44.1 million, and the facts and circumstances that led to this impairment and how the fair value of each reporting unit was estimated, including the significant assumptions used and other details, are outlined in the following section.

Interim Impairment Assessments

As disclosed in our June 30, 2023 report on Form 10-Q, we performed a quantitative goodwill impairment assessment on our Workers' Compensation Insurance reporting unit as of June 30, 2023, due to market conditions impacting that reporting unit's actual and projected results along with a broader decline in our stock price that occurred for a sustained period of time during the second quarter of 2023.

The quantitative goodwill impairment test involves comparing the fair value of a reporting unit with its carrying value including goodwill. If the fair value of a reporting unit exceeds its carrying value, the reporting unit's goodwill is considered not to be impaired. However, if the carrying value of a reporting unit exceeds its fair value, an impairment loss is recorded in an amount equal to that excess. Any impairment charge recognized is limited to the amount of the respective reporting unit's allocated goodwill.

Determining the fair value of a reporting unit under the quantitative goodwill impairment test requires judgment and often involves the use of significant estimates and assumptions, including an assessment of external factors such as macroeconomic, industry and market conditions, as well as entity-specific factors, such as actual and planned financial performance. These estimates and assumptions could have a significant impact on whether or not an impairment charge is recognized and the magnitude of any such charge. To assist management in the process of determining any potential goodwill impairment, we may review and consider appraisals from accredited independent valuation firms. Estimates of fair value are primarily determined using discounted cash flows and market comparisons. These approaches involve significant estimates and assumptions, including projected future cash flows (including timing), discount rates reflecting the risks inherent in those future cash flows, perpetual growth rates, and selection of appropriate market comparable metrics and transactions.

As a result of the interim goodwill impairment assessment in the second quarter of 2023, management concluded that the fair value of the Workers' Compensation Insurance reporting unit exceeded the carrying value as of the testing date by approximately 3%; therefore, goodwill was not impaired during the second quarter of 2023.

Market conditions impacting actual and projected results of our Workers' Compensation Insurance reporting unit persisted into the third quarter of 2023. During the third quarter of 2023, we increased our full year current accident year loss ratio and recognized unfavorable prior accident year reserve development in our Workers' Compensation Insurance reporting unit, which reflected higher than expected loss trends observed in our average cost per claim which we attribute to increased medical costs driven by wage inflation and medical advancements. As a result, management performed an updated quantitative assessment of goodwill on our Workers' Compensation Insurance reporting unit as of September 30, 2023 using updated actual and projected results as well as marketplace data. The updated data impacted a number of key variables in our analysis including the determination of a higher discount rate and lower valuation multiples.

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For each of the interim impairment assessments performed in the second and third quarters of 2023, management estimated the fair value of the Workers' Compensation Insurance reporting unit using both an income approach and a market approach using marketplace data that was current at the time of each respective analysis based on the valuation methodologies and process for developing assumptions. The estimate of fair value derived from the income approach was based on the present value of expected future cash flows, including terminal value, utilizing a market-based weighted average cost of capital determined separately for each reporting unit. The estimate of fair value derived from the market approach was based on price to book multiple data. To corroborate the reporting unit's valuation, management performed a reconciliation of the estimate of the aggregate fair value of all reporting units to ProAssurance's market capitalization as of each testing date, including consideration of a control premium. The determination of fair value involved the use of significant estimates and assumptions, including revenue growth rates, combined ratios, capital requirements, tax rates, terminal growth rates, discount rates, comparable public companies and synergistic benefits available to market participants. In addition, management made certain judgments and assumptions in allocating shared assets and liabilities to individual reporting units to determine the carrying amount of each reporting unit.

The analysis during the third quarter of 2023 indicated impairment of the goodwill associated with our Workers' Compensation Insurance reporting unit and accordingly we recorded a $44.1 million charge to fully impair the goodwill in the third quarter.

In both our second and third quarter 2023 analyses, we also estimated the fair value of our Segregated Portfolio Cell Reinsurance reporting unit using the same approaches, which indicated that the fair value of the reporting unit significantly exceeded the carrying amount for each of the interim impairment assessments performed.

Management also performed impairment tests of indefinite lived intangible assets and certain of our definite lived intangible assets for which a triggering event was deemed to have occurred. Based upon these impairment tests, no impairment of our definite or indefinite lived intangible assets was identified at June 30, 2023 or September 30, 2023.

Annual Impairment Assessment

Subsequent to performing the interim impairment assessments previously discussed, we performed our annual goodwill impairment assessment as of October 1, 2023.

When testing goodwill for impairment on our annual test date, we have the option to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more likely than not that the estimated fair value of a reporting unit is less than its carrying amount. If we elect to perform a qualitative assessment and determine that an impairment is more likely than not, we are then required to perform a quantitative impairment test; otherwise, no further analysis is required. We also may elect not to perform the qualitative assessment and, instead, proceed directly to the quantitative impairment test.

For the most recent goodwill impairment test performed on October 1, 2023, we elected to perform a qualitative impairment test for our Segregated Portfolio Cell Reinsurance reporting unit. As of the last quantitative assessment as of September 30, 2023, the Segregated Portfolio Cell Reinsurance reporting unit had a significant excess of fair value over book value and based on current operations is expected to continue to do so; therefore, our annual impairment test for this reporting unit was performed qualitatively.

Performance of the qualitative goodwill impairment assessment requires judgment in identifying and considering the significance of relevant key factors, events and circumstances that affect the fair values of our reporting units. This requires consideration and assessment of external factors such as macroeconomic, industry, and market conditions, as well as entity-specific factors, such as our actual and planned financial performance. We also give consideration to the difference between the reporting unit's fair value and carrying value as of the most recent date that a fair value measurement was performed. If the results of the qualitative assessment conclude that it is not more likely than not that the fair value of a reporting unit exceeds its carrying value, additional quantitative impairment testing is performed.

In applying the qualitative approach, management considered macroeconomic factors, industry and market conditions, cost factors that could have a negative impact on the reporting unit, actual financial performance of the reporting unit versus expectations and management's future business expectations. As a result of the qualitative assessment, management concluded that it was not more likely than not that the fair value of the Segregated Portfolio Cell Reinsurance reporting unit was less than its carrying value as of the testing date; therefore, no further impairment testing was required. Management also performed impairment tests of our indefinite lived intangible assets which indicated no impairment as of October 1, 2023.

No goodwill impairment was recorded during the years ended December 31, 2022 or 2021.

Additional information regarding our goodwill and intangible assets is included in Note 1 and Note 6 of the Notes to Consolidated Financial Statements.

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Liquidity and Capital Resources and Financial Condition

Overview

ProAssurance Corporation is a holding company and is a legal entity separate and distinct from its subsidiaries. As a holding company, our principal source of external revenue is our investment revenues. In addition, dividends from our operating subsidiaries represent another source of funds for our obligations, including debt service and shareholder dividends, if declared. We also charge our core domestic operating subsidiaries within our Specialty P&C and Workers' Compensation Insurance segments a management fee based on the extent to which services are provided to the subsidiary and the amount of gross premium written by the subsidiary. At December 31, 2023, we held cash and liquid investments of approximately $65 million outside our insurance subsidiaries that were available for use without regulatory approval or other restriction. As of February 22, 2024, we also have an additional $125 million in permitted borrowings available under our Revolving Credit Agreement as well as the possibility of a $50 million accordion feature, if successfully subscribed, as discussed in this section under the heading "Debt."

During 2023, our operating subsidiaries paid dividends to us of approximately $31 million. Our insurance subsidiaries, in the aggregate, are permitted to pay dividends of approximately $145 million over the course of 2024 without prior approval of state insurance regulators. However, the payment of any dividend requires prior notice to the insurance regulator in the state of domicile, and the regulator may reduce or prevent the dividend if, in its judgment, payment of the dividend would have an adverse effect on the surplus of the insurance subsidiary. We make the decision to pay dividends from an insurance subsidiary based on the capital needs of that subsidiary and may pay less than the permitted dividend or may also request permission to pay an additional amount (an extraordinary dividend).

Cash Flows

Cash flows between periods compare as follows:

Year Ended December 31
(In thousands)20232022Change
Net cash provided (used) by:
Operating activities$(49,885)$(29,841)$(20,044)
Investing activities141,139(61,997)203,136
Financing activities(55,315)(21,805)(33,510)
Increase (decrease) in cash and cash equivalents$35,939$(113,643)$149,582

The principal components of our operating cash flows are the excess of premiums collected and net investment income over losses paid and operating costs, including income taxes. Timing delays exist between the collection of premiums and the payment of losses associated with the premiums. Premiums are generally collected within the twelve-month period after the policy is written, while our claim payments are generally paid over a more extended period of time. Likewise, timing delays exist between the payment of claims and the collection of any associated reinsurance recoveries.

The decrease in operating cash flows of $20.0 million in 2023 as compared to 2022 was primarily due to:

•A decrease in net premium receipts of $75.1 million primarily driven by our Specialty P&C segment due to the competitive market conditions on terms and pricing and an increase in cash paid to reinsurers primarily associated with our excess of loss reinsurance arrangements. In addition, the decrease in net premium receipts reflected our ceased participation in Syndicate 6131 for the 2022 underwriting year.

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The decrease in operating cash flows was partially offset by:

•A decrease in cash paid for operating expenses of $21.8 million driven by the prior year impact of the termination of deferred compensation arrangements assumed in the NORCAL acquisition during the first quarter of 2022 totaling approximately $13.2 million and, to a lesser extent, the receipt of cash collateral to secure the net present value of future cash flows associated with the Interest Rate Swaps of $4.0 million. See further discussion on the Interest Rate Swaps in Note 11 to the Notes to Consolidated Financial Statements. Furthermore, the decrease in cash paid for operating expenses reflected the prior year impact of one-time expenses of $3.9 million in our Specialty P&C segment. One-time expenses in 2022 were mainly comprised of one-time bonuses, employee severance charges and lease exit costs.

•Proceeds of $6.9 million associated with the sale of our ownership interest in the underwriting and operations entity associated with Syndicate 1729.

•A decrease in paid losses of $6.9 million driven by our Specialty P&C segment due to an increase in losses recoverable from reinsurers, partially offset by an increase in average indemnity paid per closed claim compared to the prior year period, as claim costs in our HCPL line of business are pressured by social inflation and higher than anticipated loss severity trends.

•The effect of a tax refund of approximately $11.7 million which we received in February 2023 (see additional discussion within this section under the heading "Taxes" that follows).

•An increase in cash received from investment income of $7.5 million driven by higher average book yields as we continue to reinvest at higher rates as our portfolio matures.

The remaining variance in operating cash flows in 2023 as compared to 2022 was composed of individually insignificant components.

We manage our investing cash flows to ensure that we will have sufficient liquidity to meet our obligations, taking into consideration the timing of cash flows from our investments, including interest payments, dividends and principal payments, as well as the expected cash flows to be generated by our operations as discussed in this section under the heading "Investing Activities and Related Cash Flows."

Our financing cash flows are primarily comprised of share repurchases and dividend payments to our stockholders. See further discussion of our financing activities in this section under the heading "Financing Activities and Related Cash Flows."

Operating Activities and Related Cash Flows

Losses

The following table, known as the Analysis of Reserve Development, presents information over the preceding ten years regarding the payment of our losses as well as changes to (the development of) our estimates of losses during that time period. As noted in the table, we have completed various acquisitions over the ten year period which have affected original and re-estimated gross and net reserve balances as well as loss payments.

The table includes losses on both a direct and an assumed basis and is net of anticipated reinsurance recoverables. The gross liability for losses before reinsurance, as shown on the balance sheet, and the reconciliation of that gross liability to amounts net of reinsurance are reflected below the table. We do not discount our reserve for losses to present value. Information presented in the table is cumulative and, accordingly, each amount includes the effects of all changes in amounts for prior years. The table presents the development of our balance sheet reserve for losses; it does not present accident year or policy year development data. Conditions and trends that have affected the development of liabilities in the past may not necessarily occur in the future. Accordingly, it is not appropriate to extrapolate future redundancies or deficiencies based on this table.

The following may be helpful in understanding the Analysis of Reserve Development:

•The line entitled “Reserve for losses, undiscounted and net of reinsurance recoverables” reflects our reserve for losses and loss adjustment expense, less the receivables from reinsurers, each as reported in our Consolidated Balance Sheets at the end of each year (the Balance Sheet Reserves).

•The section entitled “Cumulative net paid, as of” reflects the cumulative amounts paid as of the end of each succeeding year with respect to the previously recorded Balance Sheet Reserves.

•The section entitled “Re-estimated net liability as of” reflects the re-estimated amount of the liability previously recorded as Balance Sheet Reserves that includes the cumulative amounts paid and an estimate of the remaining net liability based upon claims experience as of the end of each succeeding year (the Net Re-estimated Liability).

•The line entitled “Net cumulative redundancy (deficiency)” reflects the difference between the previously recorded Balance Sheet Reserve for each applicable year and the Net Re-estimated Liability relating thereto as of the end of the most recent fiscal year.

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Analysis of Reserve Development
December 31
(In thousands)20132014201520162017201820192020202120222023
Reserve for losses, undiscounted and net of reinsurance recoverables$1,825,304$1,812,299$1,730,308$1,681,423$1,659,971$1,709,129$1,878,140$1,945,099$3,059,328$2,973,196$2,888,655
Cumulative net paid, as of:
One Year Later343,197380,508370,973354,526387,389428,940466,904454,902756,601773,912
Two Years Later571,690640,655616,016621,783668,340734,638790,989813,7681,371,326
Three Years Later732,892798,636799,689800,331857,177952,3091,046,5731,101,050
Four Years Later826,384910,998898,844930,769990,0231,133,4621,249,196
Five Years Later891,615964,897974,1041,004,9511,085,2671,265,971
Six Years Later924,3341,006,2151,018,1481,061,4881,162,371
Seven Years Later952,1181,030,7821,051,4951,110,311
Eight Years Later967,9451,045,9801,078,647
Nine Years Later976,0741,066,063
Ten Years Later989,502
Re-estimated net liability as of:
End of Year1,825,3041,812,2991,730,3081,681,4231,659,9711,709,1291,878,1401,945,0993,059,3282,973,196
One Year Later1,644,5161,651,1171,587,0291,547,8761,565,8671,696,8931,827,1531,902,8133,015,2412,975,793
Two Years Later1,483,3781,511,5421,460,6601,444,6191,487,9051,656,6151,805,4331,885,4563,025,786
Three Years Later1,358,5601,388,6821,356,0751,337,5711,446,5711,647,2831,792,2021,890,578
Four Years Later1,252,6051,288,5641,257,6501,306,2741,432,4771,632,8361,768,451
Five Years Later1,173,9751,221,4631,231,7131,299,0321,415,0771,605,374
Six Years Later1,126,3081,204,6421,230,5621,287,7311,394,624
Seven Years Later1,121,0871,199,6541,217,7131,277,884
Eight Years Later1,119,9841,183,9731,216,727
Nine Years Later1,110,2161,186,762
Ten Years Later1,113,744
Net cumulative redundancy (deficiency)$711,560$625,537$513,581$403,539$265,347$103,755$109,689$54,521$33,542$(2,597)
Original gross liability - end of year$2,072,822$2,052,768$1,990,266$1,961,436$1,971,303$2,037,274$2,243,133$2,295,279$3,469,417$3,373,260
Reinsurance recoverables(247,518)(240,469)(259,958)(280,013)(311,332)(328,145)(364,993)(350,180)(410,089)(400,064)
Original net liability - end of year$1,825,304$1,812,299$1,730,308$1,681,423$1,659,971$1,709,129$1,878,140$1,945,099$3,059,328$2,973,196
Gross re-estimated liability - latest$1,262,942$1,365,998$1,435,036$1,512,793$1,633,380$1,897,220$2,107,517$2,228,095$3,490,781$3,431,876
Re-estimated reinsurance recoverables(149,198)(179,236)(218,309)(234,909)(238,756)(291,846)(339,066)(337,517)(464,995)(456,083)
Net re-estimated liability - latest$1,113,744$1,186,762$1,216,727$1,277,884$1,394,624$1,605,374$1,768,451$1,890,578$3,025,786$2,975,793
Gross cumulative redundancy (deficiency)$809,880$686,770$555,230$448,643$337,923$140,054$135,616$67,184$(21,364)$(58,616)

See table notes on following page.

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Table Notes

•We have elected to present reserve history for acquired entities on a prospective basis in the table above; therefore, certain items will not agree to the following table which details activity in our net reserve for losses.

•Given the Lloyd's Syndicates line of business reserve is relatively small on a standalone basis as compared to our consolidated reserve, we have elected to exclude its reserve history for all periods presented in the table above, which is consistent with prior year; therefore, certain items will not agree to the following table which details activity in our net reserve for losses.

•Reserves for 2013 include gross and net reserves acquired in 2013 business combinations of $201.1 million and $126.0 million, respectively.

•Reserves for 2014 include gross and net reserves acquired in 2014 business combinations of $153.2 million and $139.5 million, respectively.

•Reserves for 2021 include gross and net reserves acquired in 2021 business combinations of $1.2 billion and $1.1 billion, respectively.

In each year reflected in the table, we have estimated our reserve for losses utilizing the management and actuarial processes discussed under the heading "Reserve for Losses and Loss Adjustment Expenses" in the Critical Accounting Estimates section. Factors that have contributed to the variation in loss development are primarily related to the extended period of time required to resolve professional liability claims and include the following:

•The HCPL legal environment deteriorated in the late 1990’s and severity began to increase at a greater pace than anticipated in our rates and reserve estimates. We addressed the adverse severity trends through increased rates, stricter underwriting and modifications to claims handling procedures, and reflected this adverse severity trend when we established our initial reserves for subsequent years.

•These adverse severity trends later moderated, with that moderation becoming more pronounced beginning in 2009. We were cautious in giving full recognition to indications that the pace of severity increase had slowed, however we gave measured recognition of the improved trend in our reserve estimates. The favorable development was most pronounced for years 2004 to 2008, as the initial reserves for these accident years were established prior to substantial indication that severity trends were moderating. We gave stronger recognition to the lower severity trend as time elapsed and a greater percentage of claims were closed.

•A general decline in claims frequency has also been a contributor to favorable loss development. A significant portion of our policies through 2003 were issued on an occurrence basis, and a smaller portion of our ongoing business results from the issuance of extended reporting endorsements which have occurrence-like exposure. As claims frequency declined, the number of reported claims related to these coverages was less than originally expected.

•Beginning in 2017, we identified potential higher severity trends in the broader HCPL industry. These trends were also reflected in increases in estimates of ultimate losses for open HCPL claims for earlier accident years, which resulted in a lower amount of favorable development recognized in 2018 and 2017 as compared to prior years.

•During 2019 the loss experience in our Specialty line of business in our Specialty P&C segment deteriorated further, particularly in regard to the reserves we established for a large national healthcare account that experienced losses far exceeding the assumptions we made when underwriting the account, beginning in 2016. As a result, we strengthened our Specialty reserves through the recognition of net unfavorable development on prior accident years and a higher current accident year net loss ratio in our Specialty P&C segment in 2019.

•The loss environment in our HCPL line of business in our Specialty P&C segment continues to be challenging in some jurisdictions, as claim costs are pressured by social inflation and higher than anticipated loss severity trends which started to emerge in the fourth quarter of 2022. During the first quarter of 2023, we strengthened case reserves related to four large claims through the recognition of unfavorable development on prior accident years. Further, beginning in the second half of 2023, we observed higher than expected loss trends in our average cost per claim in our Workers' Compensation Insurance segment which we primarily attribute to increased medical costs driven by wage inflation and medical advancements. In response to these trends, we increased both our current accident year loss ratio and prior year reserves in our Workers' Compensation Insurance segment.

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Activity in our net reserve for losses during 2023, 2022 and 2021 is summarized below:

Year Ended December 31
(In thousands)202320222021
Balance, beginning of year$3,471,147$3,579,940$2,417,179
Less reinsurance recoverables on unpaid losses and loss adjustment expenses431,889451,741385,087
Net balance, beginning of year3,039,2583,128,1992,032,092
Net reserves acquired from acquisitions1,089,103
Net losses:
Current year(1)794,848813,515797,732
(Favorable) unfavorable development of reserves established in prior years, net(1)5,646(36,753)(45,483)
Total800,494776,762752,249
Paid related to:
Current year(101,996)(108,139)(109,925)
Prior years(782,048)(757,564)(635,320)
Total paid(884,044)(865,703)(745,245)
Net balance, end of year2,955,7083,039,2583,128,199
Plus reinsurance recoverables on unpaid losses and loss adjustment expenses445,573431,889451,741
Balance, end of year$3,401,281$3,471,147$3,579,940

(1) Current year net losses and prior accident year development for the years ended December 31, 2023, 2022 and 2021 includes certain purchase accounting adjustments associated with our acquisition of NORCAL. See Note 7 of the Notes to Consolidated Financial Statements for additional information.

At December 31, 2023 our gross reserve for losses included case reserves of approximately $2.3 billion and IBNR reserves of approximately $1.2 billion. Our consolidated gross reserve for losses on a GAAP basis exceeds the combined gross reserves of our insurance subsidiaries on a statutory basis by approximately $0.2 billion, which is principally due to the portion of the GAAP reserve for losses that is reflected for statutory accounting purposes as unearned premiums. These unearned premiums are applicable to extended reporting endorsements (“tail” coverage) issued without a premium charge upon death, disability or retirement of an insured who meets certain qualifications.

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Reinsurance

Within our Specialty P&C segment, we use insurance and reinsurance (collectively, “reinsurance”) to provide capacity to write larger limits of liability, to provide reimbursement for losses incurred under the higher limit coverages we offer and to provide protection against losses in excess of policy limits. Within our Workers' Compensation Insurance segment, we use reinsurance to reduce our net liability on individual risks, to mitigate the effect of significant loss occurrences (including catastrophic events), to stabilize underwriting results and to increase underwriting capacity by decreasing leverage. In both our Specialty P&C and Workers' Compensation Insurance segments, we use reinsurance in risk sharing arrangements to align our objectives with those of our strategic business partners and to provide custom insurance solutions for large customer groups. The purchase of reinsurance does not relieve us from the ultimate risk on our policies; however, it does provide reimbursement for certain losses we pay. We pay our reinsurers a premium in exchange for reinsurance of the risk. In certain of our excess of loss arrangements, the premium due to the reinsurer is determined by the loss experience of the business reinsured, subject to certain minimum and maximum amounts. Until all loss amounts are known, we estimate the premium due to the reinsurer. Changes to the estimate of premium owed under reinsurance agreements related to prior periods are recorded in the period in which the change in estimate occurs and can have a significant effect on net premiums earned.

We offer alternative market solutions whereby we cede certain premiums from our Workers' Compensation Insurance and Specialty P&C segments to either the SPCs at Inova Re, one of our Cayman Islands reinsurance subsidiaries which is reported in our Segregated Portfolio Cell Reinsurance segment, or captive insurers unaffiliated with ProAssurance for two programs. The majority of these policies are reinsured to the SPCs at Inova Re, net of a ceding commission. See further discussion on our SPC operations in the Segment Results - Segregated Portfolio Cell Reinsurance section that follows. The alternative market workers' compensation policies are ceded from our Workers' Compensation Insurance segment to the SPCs under 100% quota share reinsurance agreements. The alternative market healthcare professional liability policies are ceded from our Specialty P&C segment to the SPCs under either excess of loss or quota share reinsurance agreements, depending on the structure of the individual program. The portion of the risk that is not ceded to an SPC is retained in our Specialty P&C segment and may also be reinsured under our standard healthcare professional liability reinsurance program, depending on the policy limits provided. The remaining premium written in our alternative market business is 100% ceded to unaffiliated captive insurers.

Excess of Loss Reinsurance Agreements

We generally reinsure risks under treaties (our excess of loss reinsurance agreements) pursuant to which the reinsurers agree to assume all or a portion of all risks that we insure above our individual risk retention levels, up to the maximum individual limits offered. Generally, these agreements are negotiated and renewed annually. Our HCPL and Medical Technology Liability treaties renew annually on October 1 and our Workers' Compensation treaty renews annually on May 1. Our HCPL and Medical Technology Liability treaties renewed October 1, 2023 at a higher rate than the previous treaties and retention of HCPL coverages in excess of $2 million increased to 9% to 9.5% from 0% to 5% of the next $24 million of risk; all other material terms were consistent with the expiring treaties. Our traditional Workers' Compensation treaty renewed May 1, 2023 at a higher rate than the previous treaty; all other material terms were consistent with the expiring treaty. The significant coverages provided by our current excess of loss reinsurance agreements are depicted in the following table.

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Excess of Loss Reinsurance Agreements

Column 1Column 2Column 3Column 4Column 5Column 6
Healthcare Professional LiabilityMedical Technology & Life Sciences ProductsWorkers' Compensation - Traditional

(1) Effective October 1, 2020, one prepaid limit reinstatement of $21M and a second limit reinstatement of up to $21M for the second layer, subject to reinstatement premium, which attaches after the first reinstatement has been completely exhausted. All limit reinstatements thereafter require no additional premium. Effective October 1, 2021, limits can be reinstated a maximum of four times.

(2) Prior to October 1, 2020, retention was $1M.

(3) Historically, retention has ranged from 0% to 32.5%.

(4) Historically, retention has ranged from $1M to $2M.

(5) Subject to a limit of $20M per individual claimant. If an individual loss were to exceed this level the Company would retain this excess exposure.

(6) Subject to an AAD where retention is 3.5% of subject earned premium in annual losses otherwise recoverable in excess of the $500K retention per loss occurrence.

Large HCPL risks that are above the limits of our basic reinsurance treaties may be reinsured on a facultative basis, whereby the reinsurer agrees to insure a particular risk up to a designated limit. We also have in place a number of risk sharing arrangements that apply to the first $1 million of losses for certain large healthcare systems and other insurance entities, as well as with certain insurance agencies that produce business for us.

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Other Reinsurance Arrangements

For the workers' compensation business ceded to Inova Re; each SPC has in place its own reinsurance arrangements, which are illustrated in the following table.

Segregated Portfolio Cell Reinsurance

Column 1Column 2Column 3
Per Occurrence CoverageAggregate Coverage

(1) The attachment point is based on a percentage of written premium within individual cells, ranges from 85% to 94%, and varies by cell.

Each SPC has participants and the profit or loss of each cell accrues fully to these cell participants. As previously discussed, we participate in certain SPCs to a varying degree. Each SPC maintains a loss fund initially equal to the difference between premium assumed by the cell and the ceding commission. The external participants of each cell provide collateral to us, typically in the form of a letter of credit that is initially equal to the difference between the loss fund of the SPC (amount of funds available to pay losses after deduction of ceding commission) and the aggregate attachment point of the reinsurance. Over time, an SPC's retained profits are considered in the determination of the collateral amount required to be provided by the cell's external participants.

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Taxes

We are subject to the tax laws and regulations of the U.S., Cayman Islands and U.K. We file a consolidated U.S. federal income tax return that includes the parent company and its U.S. subsidiaries, except for ProAssurance American Mutual, A Risk Retention Group. Our filing obligations include a requirement to make quarterly payments of estimated taxes to the IRS using the corporate tax rate effective for the tax year. We did not make any quarterly estimated tax payments during the year ended December 31, 2023 as we expect NOL carryforwards to offset any income taxes due.

As a result of the CARES Act that was signed into law on March 27, 2020 we were permitted to carryback NOLs generated in tax years 2019 and 2020 for up to five years. See further discussion in the Critical Accounting Estimates section under the heading "U.S. Tax Legislation" and Note 5 of the Notes to Consolidated Financial Statements. We generated an NOL of approximately $33.3 million from the 2020 tax year that was carried back to the 2015 tax year that resulted in a tax refund of approximately $11.7 million which was received in February 2023. In addition, the CARES Act included the initial version of the ERC which was extended and expanded in December 2020 and March 2021. See further discussion of the ERC in Note 1 of the Notes to Consolidated Financial Statements. As an eligible employer under the provisions of the CARES Act, NORCAL filed a claim for a payroll tax refund of approximately $3.8 million during the second quarter of 2023, based on eligible wages paid during 2020.

As a result of the NORCAL acquisition, we have U.S. federal NOL carryforwards, which were approximately $32.3 million as of December 31, 2023. These NOL carryforwards are subject to limitation by Internal Revenue Code Section 382 and will begin to expire in 2035.

Investing Activities and Related Cash Flows

Our investments at December 31, 2023 and December 31, 2022 are comprised as follows:

December 31, 2023December 31, 2022
($ in thousands)Carrying Value% of Total InvestmentCarrying Value% of Total Investment
Fixed maturities, available for sale:
U.S. Treasury obligations$243,5255%$221,6085%
U.S. Government-sponsored enterprise obligations18,7241%19,9341%
State and municipal bonds454,38110%439,45010%
Corporate debt1,750,57440%1,781,45241%
Residential mortgage-backed securities430,13710%389,5408%
Commercial mortgage-backed securities197,8615%203,7945%
Other asset-backed securities398,3959%416,6949%
Total fixed maturities, available-for-sale3,493,59780%3,472,47279%
Fixed maturities, trading48,3241%43,4341%
Total fixed maturities3,541,92181%3,515,90680%
Equity investments(1)151,2954%143,7383%
Short-term investments235,7855%245,3136%
BOLI78,2052%81,7462%
Investment in unconsolidated subsidiaries276,7566%305,2107%
Other investments65,8192%95,7702%
Total investments$4,349,781100%$4,387,683100%
(1)Includes $114.9 million and $112.1 million of investment grade bond funds as of December 31, 2023 and 2022, respectively, which are not subject to significant equity price risk.

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At December 31, 2023, 99% of our investments in available-for-sale fixed maturity securities were rated and the average rating was A+. The distribution of our investments in available-for-sale fixed maturity securities by rating were as follows:

December 31, 2023December 31, 2022
($ in thousands)Carrying Value% of Total InvestmentCarrying Value% of Total Investment
Rating*
AAA$489,12114%$1,008,23029%
AA+689,49120%113,6593%
AA206,4716%210,2476%
AA-180,8275%190,1065%
A+286,7238%264,9508%
A410,93512%432,44212%
A-374,61211%345,67110%
BBB+194,1405%213,7946%
BBB286,3788%305,9879%
BBB-138,3994%137,5964%
Below investment grade233,4056%249,4007%
Not rated3,0951%3901%
Total$3,493,597100%$3,472,472100%
*Average of three NRSRO sources, presented as an S&P equivalent. Source: S&P, Copyright ©2023, S&P Global Market Intelligence

A detailed listing of our investment holdings as of December 31, 2023 is located under the Financial Information heading on the Investor Relations page of our website which can be reached directly at https://investor.proassurance.com/financial-information/quarterly-investment-supplements/default.aspx or through links from the Investor Relations section of our website, investor.proassurance.com.

We manage our investments to ensure that we will have sufficient liquidity to meet our obligations, taking into consideration the timing of cash flows from our investments, including interest payments, dividends and principal payments, as well as the expected cash flows to be generated or used by our operations. In addition to the interest and dividends we will receive from our investments, we anticipate that between $70 million and $140 million of our portfolio will mature (or be paid down) each quarter over the next twelve months and become available, if needed, to meet our cash flow requirements. In response to higher severity trends and an increase in paid losses in our HCPL line of business and our Workers' Compensation Insurance segment, we have reduced the rate of reinvestment of these cash flows in order to allow for additional cash availability. The primary outflow of cash at our insurance subsidiaries is related to paid losses and operating costs, including income taxes. The payment of individual claims cannot be predicted with certainty; therefore, we rely upon the history of paid claims in estimating the timing of future claims payments with consideration given to current and anticipated industry trends and macroeconomic conditions. To the extent that we may have an unanticipated shortfall in cash, we may either liquidate securities or borrow funds under existing borrowing arrangements through our Revolving Credit Agreement and the FHLB system. As of February 22, 2024, $175 million could be made available for use through our Revolving Credit Agreement, as discussed in this section under the heading "Debt." Given the duration of our investments, we do not foresee a shortfall that would require us to meet operating cash needs through additional borrowings. Additional information regarding our Revolving Credit Agreement is detailed in Note 10 of the Notes to Consolidated Financial Statements.

At December 31, 2023, our FAL was comprised of investment securities, primarily available-for-sale fixed maturity securities, and a nominal amount of cash and cash equivalents deposited with Lloyd's which had a fair value of $20 million. During the second quarter of 2023, we received a return of approximately $4.1 million of cash from our FAL balances related to the settlement of our participation in the results of Syndicate 1729 and Syndicate 6131 for the 2020 underwriting year. Given that we decided to no longer participate in the results of Syndicate 1729 beginning with the 2024 underwriting year, we expect to receive an additional return of FAL in the future; however, the amount of which cannot be estimated at this time. Furthermore, we received proceeds of $6.8 million associated with the sale of our remaining ownership interest in the underwriting and operations entity associated with Syndicate 1729 to unrelated third parties during 2023. Additional information regarding our FAL is detailed in Note 3 of the Notes to Consolidated Financial Statements.

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Our investment portfolio continues to be primarily composed of high quality fixed income securities with approximately 93% of our fixed maturities being investment grade securities as determined by national rating agencies. The weighted average effective duration of our fixed maturity securities at December 31, 2023 was 3.25 years; the weighted average effective duration of our fixed maturity securities combined with our short-term securities was 3.05 years.

The carrying value and unfunded commitments for certain of our investments were as follows:

Carrying ValueDecember 31, 2023
($ in thousands, except expected funding period)December 31, 2023December 31, 2022Unfunded CommitmentExpected funding period in years
Qualified affordable housing project tax credit partnerships (1)$666$4,088$1183
All other investments, primarily investment fund LPs/LLCs276,090301,122145,5664
Total$276,756$305,210$145,684
(1) The carrying value reflects our total commitments (both funded and unfunded) to the partnerships, less any amortization, since our initial investment. We fund these investments based on funding schedules maintained by the partnerships.

Investment fund LPs/LLCs are by nature less liquid and may involve more risk than other investments. We manage our risk through diversification of asset class and geographic location. At December 31, 2023, we had investments in 34 separate investment funds with a total carrying value of $276.1 million which represented approximately 6% of our total investments. Our investment fund LPs/LLCs generate earnings from trading portfolios, secured debt, debt securities, multi-strategy funds and private equity investments, and the performance of these LPs/LLCs is affected by the volatility of equity and credit markets. For our investments in LPs/LLCs, we record our allocable portion of the partnership operating income or loss as the results of the LPs/LLCs become available, typically following the end of a reporting period.

Financing Activities and Related Cash Flows

Treasury Shares

Treasury share activity for 2023, 2022 and 2021 was as follows:

(Share amounts in thousands)202320222021
Treasury shares at the beginning of the period9,4649,3259,325
Shares reacquired, at cost of $50.5 million and $3.3 million for 2023 and 2022, respectively3,143139
Treasury shares at the end of the period12,6079,4649,325

We did not repurchase any common shares subsequent to December 31, 2023, and as of February 22, 2024, our remaining Board authorization was approximately $55.9 million.

ProAssurance Shareholder Dividends

Our Board declared cash dividends during 2023, 2022 and 2021 as follows:

Quarterly Cash Dividends Declared, per Share
202320222021
First Quarter$0.05$0.05$0.05
Second Quarter$$0.05$0.05
Third Quarter$$0.05$0.05
Fourth Quarter$$0.05$0.05

Each dividend was paid in the month following the quarter in which it was declared. Cash dividends totaling $5 million were paid during the year ended December 31, 2023 and cash dividends totaling $11 million were paid during each of the years ended December 31, 2022 and 2021. In light of the price range in which our stock traded in the second quarter of 2023, the Board decided to suspend payment of a quarterly cash dividend. Instead, we used available capital to repurchase common shares pursuant to the existing share repurchase authorization. Any decision to pay future cash dividends is subject to the Board’s final determination after a comprehensive review of financial performance, future expectations and other factors deemed relevant by the Board.

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Debt

Our outstanding debt consisted of the following:

($ in thousands)December 31, 2023December 31, 2022
Senior Notes due 2023$$250,000
Contribution Certificates179,387177,525
Revolving Credit Agreement125,000
Term Loan125,000
Total principal429,387427,525
Less unamortized debt issuance costs2,254542
Debt less unamortized debt issuance costs$427,133$426,983

NORCAL Insurance Company, successor to NORCAL Mutual Insurance Company, issued Contribution Certificates, which bear interest at 3.0% annually and are due in 2031, to certain NORCAL policyholders in the conversion. The Contribution Certificates have a principal amount of $191 million and were recorded at their fair value of $175 million at the date of the NORCAL acquisition on May 5, 2021. The difference of $16 million between the recorded acquisition date fair value and the principal balance of the Contribution Certificates will be accreted utilizing the effective interest method over the term of the certificates of ten years as an increase to interest expense. Furthermore, interest payments are subject to deferral if we do not receive permission from the California Department of Insurance prior to payment. We received permission from the California Department of Insurance to pay the annual interest payment, which was paid in April 2023. There are no financial covenants associated with these certificates.

On April 28, 2023, we executed an amendment to the Revolving Credit Agreement, which extended the expiration from November 2024 to April 2028 and included an additional $125 million delayed draw Term Loan. The amended Revolving Credit Agreement may be used for general corporate purposes, including, but not limited to, short-term working capital, share repurchases as authorized by the Board and support for other activities. Our amended Revolving Credit Agreement permits borrowings of up to $250 million as well as the possibility of a $50 million accordion feature, if successfully subscribed. The Term Loan is available to be drawn up to $125 million during a five year period after closing, subject to customary borrowing conditions. We drew on the Revolving Credit Agreement and funded the Term Loan to refinance our Senior Notes in November 2023. We are in compliance with the financial covenants of the Revolving Credit Agreement.

Additional information regarding our debt is provided in Note 10 of the Notes to Consolidated Financial Statements.

To manage our exposure to interest rate risk due to variability in the base rate on borrowings under the amended Revolving Credit Agreement and Term Loan, we entered into two forward-starting interest rate swap agreements ("Interest Rate Swaps") on May 2, 2023, each with an effective date of December 29, 2023 and maturity date of March 31, 2028. Additional information regarding our Interest Rate Swaps is provided in Note 1 and Note 11 of the Notes to Consolidated Financial Statements.

Three of our insurance subsidiaries are members of an FHLB. Through membership, those subsidiaries have access to secured cash advances which can be used for liquidity purposes or other operational needs. In order for us to use FHLB proceeds, regulatory approvals may be required depending on the nature of the transaction. To date, those subsidiaries have not materially utilized their membership for borrowing purposes.

Contingent Consideration

Contingent consideration is measured at fair value on the date of acquisition and remeasured at fair value each subsequent reporting period. Fair value of a liability represents the price that would be paid to transfer the liability in an orderly transaction between market participants at the measurement date considering characteristics specific to the liability. The purchase consideration in the NORCAL acquisition included contingent consideration. NORCAL policyholders who elected to receive NORCAL stock and tender it to ProAssurance are eligible for a share of contingent consideration in an amount of up to approximately $84 million. As defined in the purchase agreement, the contingent consideration is dependent upon the after-tax development of NORCAL's ultimate net losses for accident years ended on or before December 31, 2020 determined as of December 31, 2023 by a mutually agreed upon independent actuarial consultant. This independent actuarial consultant has until June 30, 2024 to complete their estimate.

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Given the contingent consideration associated with the NORCAL acquisition is dependent upon the after-tax development of NORCAL's ultimate net losses between December 31, 2020 and December 31, 2023, we bifurcate changes in the contingent consideration each period between fair value changes and, if applicable, changes in estimates of NORCAL's ultimate net losses for accident years 2020 and prior. See further discussion regarding our estimates of ultimate net losses in this section under the heading "Reserve for Losses and Loss Adjustment Expenses" in the Critical Accounting Estimates section. Changes in the contingent consideration related to fair value are recognized in earnings as a component of net investment gains (losses) and changes in the contingent consideration related to changes in estimates of NORCAL's ultimate net losses for accident years 2020 and prior are recognized in earnings as component of operating expenses.

As of December 31, 2023 and December 31, 2022, the contingent consideration liability was $6.5 million and $15.0 million, respectively, carried at fair value utilizing a stochastic model (see Note 2 of the Notes to Consolidated Financial Statements). This estimate of fair value does not guarantee nor suggest that contingent consideration will ultimately be paid, and any amounts ultimately paid by the Company may be greater than or less than the $6.5 million current fair value estimate. As of December 31, 2023, our current analysis of NORCAL's reserves related to accident years 2020 and prior suggests that no contingent consideration will be due; however, the actual amount due to be paid, if any, will be determined based on an analysis to be performed by an independent actuary, as previously discussed. This remaining uncertainty is a significant component in the determination of the fair value of the liability as of December 31, 2023. See further discussion around the contingent consideration and the NORCAL acquisition in Note 2 and Note 8 of the Notes to Consolidated Financial Statements.

During the years ended December 31, 2023 and 2022, we recorded an $8.5 million and $9.0 million decrease to the contingent consideration liability, respectively. The decrease recorded during the year ended December 31, 2023 was comprised of $5.0 million related to the remeasurement of the liability to fair value and $3.5 million related to the impact of unfavorable development recognized in 2023 on NORCAL's reserves related to accident years 2020 and prior. The entire decrease in the liability of $9.0 million during the year ended December 31, 2022 related to the remeasurement of the liability to fair value. See further discussion that follows under the heading "Results of Operations."

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Results of Operations - Year Ended December 31, 2023 Compared to Year Ended December 31, 2022

Selected consolidated financial data for each period is summarized in the table below.

Year Ended December 31
($ in thousands, except per share data)20232022Change
Revenues:
Net premiums written$985,994$1,014,137$(28,143)
Net premiums earned$977,397$1,029,581$(52,184)
Net investment result135,210100,86034,350
Net investment gains (losses)13,828(33,157)46,985
Other income10,7779,4041,373
Total revenues1,137,2121,106,68830,524
Expenses:
Net losses and loss adjustment expenses800,494776,76223,732
Underwriting, policy acquisition and operating expenses300,744307,338(6,594)
SPC U.S. federal income tax expense (benefit)1,6291,759(130)
SPC dividend expense (income)6,2346,673(439)
Interest expense23,15020,3722,778
Goodwill impairment44,11044,110
Total expenses1,176,3611,112,90463,457
Income (loss) before income taxes(39,149)(6,216)(32,933)
Income tax expense (benefit)(545)(5,814)5,269
Net income (loss)$(38,604)$(402)$(38,202)
Non-GAAP operating income (loss)$(7,331)$22,911$(30,242)
Earnings (loss) per share:
Basic$(0.73)$(0.01)$(0.72)
Diluted$(0.73)$(0.01)$(0.72)
Non-GAAP operating income (loss) per share:
Basic$(0.14)$0.42$(0.56)
Diluted$(0.14)$0.42$(0.56)
Net loss ratio81.9%75.4%6.5 pts
Underwriting expense ratio30.8%29.9%0.9 pts
Combined ratio112.7%105.3%7.4 pts
Operating ratio99.6%96.0%3.6 pts
Effective tax rate1.4%93.5%(92.1 pts)
Return on equity*(3.5%)%(3.5 pts)
Non-GAAP operating return on equity*(0.7%)1.8%(2.5 pts)
*See further discussion on this calculation in the Executive Summary of Operations section under the heading "Non-GAAP Operating ROE."
In all tables that follow, the abbreviation "nm" indicates that the information or the percentage change is not meaningful.

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Executive Summary of Operations

The following sections provide an overview of our consolidated and segment results of operations for the year ended December 31, 2023 as compared to the year ended December 31, 2022. See the Segment Results sections that follow for additional information regarding each segment's results. For a full discussion of the changes in the financial condition, results of operations and cash flows for the year ended December 31, 2022 as compared to the year ended December 31, 2021, please refer to Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" section of ProAssurance's December 31, 2022 report on Form 10-K. Any significant retrospective revisions in the presentation of the changes in the financial condition, results of operations and cash flows for the year ended December 31, 2022 as compared to the year ended December 31, 2021 as reported in ProAssurance's December 31, 2022 report on Form 10-K are located in this report under the section that follows titled "Results of Operations - Year Ended December 31, 2022 Compared to Year Ended December 31, 2021."

Revenues

The following table shows our consolidated and segment net premiums earned:

Year Ended December 31
($ in thousands)20232022Change
Net premiums earned
Specialty P&C$755,817$793,400$(37,583)(4.7%)
Workers' Compensation Insurance160,034166,371(6,337)(3.8%)
Segregated Portfolio Cell Reinsurance61,54669,810(8,264)(11.8%)
Consolidated total$977,397$1,029,581$(52,184)(5.1%)

For the year ended December 31, 2023, consolidated net premiums decreased $52.2 million as compared to 2022.

•For our Specialty P&C segment, net premiums earned decreased during 2023 as compared to 2022 due to the pro rata effect of a decrease in the volume of premium written during the preceding twelve months primarily due to competitive market conditions as well as our process of evaluating the NORCAL book of business and implementing ProAssurance's underwriting strategies in 2022, which impacted earned premium in 2023.

•For our Workers' Compensation Insurance segment, net premiums earned decreased in 2023 due to the continuation of competitive market conditions and reinsurance reinstatement premium of $1.6 million recorded in 2023 related to a reserve increase on a prior year reinsured claim, partially offset by an increase in the carried EBUB estimate of $2.9 million in 2023 as compared to $1.5 million in 2022.

•Net premiums earned in our Segregated Portfolio Cell Reinsurance segment decreased during 2023 due to the continuation of competitive workers' compensation market conditions and a decrease in audit premium billed to policyholders.

The following table shows our consolidated net investment result:

Year Ended December 31
($ in thousands)20232022Change
Net investment income$128,419$95,972$32,44733.8%
Equity in earnings (loss) of unconsolidated subsidiaries*6,7914,8881,90338.9%
Net investment result$135,210$100,860$34,35034.1%
*Equity in earnings (loss) of unconsolidated subsidiaries includes our share of the operating results of interests we hold in certain LPs/LLCs as well as operating losses associated with our tax credit partnership investments, which are designed to generate returns in the form of tax credits and tax-deductible project operating losses. We record our allocable portion of the partnership operating income or loss as the results of the LPs/LLCs become available, typically following the end of a reporting period.

The increase in our consolidated net investment income for the year ended December 31, 2023 as compared to 2022 reflected higher average book yields as we continue to reinvest at higher rates as our portfolio matures. Our equity in earnings of unconsolidated subsidiaries increased in 2023 as compared to 2022 driven by lower amortization of tax credit operating losses, partially offset by the performance of several LP/LLCs, which reflected lower market valuations during the fourth quarter of 2022 and first quarter of 2023.

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The following table shows our total consolidated net investment gains (losses):

Year Ended December 31
($ in thousands)20232022Change
Net impairment losses recognized in earnings$(3,111)$(1,758)$(1,353)77.0%
Other net investment gains (losses)(1)16,939(31,399)48,338153.9%
Net investment gains (losses)$13,828$(33,157)$46,985141.7%
(1) Consolidated other net investment gains (losses) in 2023 and 2022 include gains of $5.0 million and $9.0 million, respectively, reflecting the change in the fair value of contingent consideration issued in connection with the NORCAL acquisition (see Note 2 and Note 8 of the Notes to Consolidated Financial Statements). We do not consider these adjustments in assessing the financial performance of any of our segments and therefore, we have excluded them from the Segment Results sections that follow. See Note 16 of the Notes to Consolidated Financial Statements for a reconciliation of our segment results to our consolidated results.

For the year ended December 31, 2023, we recognized $3.1 million of credit-related impairment losses in earnings. We did not recognize any non-credit impairment losses in OCI during the year ended December 31, 2023. The credit-related impairment losses recognized during the year ended December 31, 2023 related to a mortgage-backed security and two corporate bonds in the financial sector. For the year ended December 31, 2022, we recognized credit-related impairment losses in earnings of $1.8 million and a nominal amount of non-credit impairment losses in OCI. The credit-related and non-credit impairment losses in OCI during the year ended December 31, 2022 related to a corporate bond in the consumer sector as well as certain mortgage-backed and other asset backed securities. Additional information regarding investment impairment losses is provided in Note 3 of the Notes to Consolidated Financial Statements.

We recognized $16.9 million of other net investment gains for the year ended December 31, 2023 driven by unrealized holding gains resulting from changes in the fair value of our convertible securities and equity investments, to a lesser extent, the remeasurement of the contingent consideration liability. We recognized $31.4 million of other net investment losses for the year ended December 31, 2022 driven by unrealized holding losses resulting from changes in the fair value of our equity investments and convertible securities and, to a lesser extent, realized losses from the sale of equity investments.

Consolidated other income for the year ended December 31, 2023 as compared to 2022 was comprised as follows:

Year Ended December 31
($ in thousands)20232022Change
Foreign currency exchange rate gains/(losses)$(2,993)$2,022$(5,015)(248.0%)
Other13,7707,3826,38886.5%
Other income$10,777$9,404$1,37314.6%

Excluding the foreign currency exchange rate gains (losses), other income increased for the year ended December 31, 2023 as compared to 2022 driven by proceeds of $6.9 million received in 2023 associated with the sale of our remaining ownership interest in the underwriting and operations entity associated with Syndicate 1729 to unrelated third parties.

Foreign currency exchange rate changes are primarily related to foreign currency denominated loss reserves associated with premium assumed from an international medical professional liability insured in our Specialty P&C segment. Our participation in this program has grown in recent years which has led to greater volatility in our results of operations even with nominal movements in exchange rates given the size of the reserve. We mitigate foreign exchange exposure by generally matching the currency and duration of associated investments to the corresponding loss reserves. In accordance with GAAP, the impact on the market value of available-for-sale fixed maturities due to changes in foreign currency exchange rates is reflected as part of OCI. Conversely, the impact of changes in foreign currency exchange rates on loss reserves is reflected through net income (loss) as a component of other income. The effect of exchange rate changes on foreign currency denominated loss reserves are reported in our Corporate segment to be consistent with the reporting of the foreign currency denominated invested assets and associated investment income.

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Expenses

The following table shows our consolidated and segment net loss ratios and net prior accident year reserve development.

Year Ended December 31
($ in millions)20232022Change
Current accident year net loss ratio
Consolidated ratio81.3%79.0%2.3pts
Specialty P&C82.6%81.7%0.9pts
Workers' Compensation Insurance81.3%71.8%9.5pts
Segregated Portfolio Cell Reinsurance65.5%65.3%0.2pts
Calendar year net loss ratio
Consolidated ratio81.9%75.4%6.5pts
Specialty P&C82.7%78.9%3.8pts
Workers' Compensation Insurance87.1%67.0%20.1pts
Segregated Portfolio Cell Reinsurance59.1%56.3%2.8pts
Favorable (unfavorable) reserve development, prior accident years
Consolidated$(5.6)$36.8$(42.4)
Specialty P&C$(0.3)$22.5$(22.8)
Workers' Compensation Insurance$(9.3)$8.0$(17.3)
Segregated Portfolio Cell Reinsurance$4.0$6.3$(2.3)

The primary drivers of the change in our consolidated current accident year net loss ratio for the year ended December 31, 2023 as compared to 2022 were as follows:

(In percentage points)Increase (Decrease) 2023 versus 2022
Estimated ratio increase (decrease) attributable to:
Specialty P&C (1)0.1 pts
Workers' Compensation Insurance1.6 pts
Segregated Portfolio Cell Reinsurance0.1 pts
NORCAL Acquisition - Purchase Accounting Adjustment0.5 pts
Increase in the consolidated current accident year net loss ratio2.3 pts
(1) Excludes the impact of the purchase accounting adjustment associated with the NORCAL acquisition.

•The increase in the current accident year net loss ratio in our Workers' Compensation Insurance segment for the year ended December 31, 2023 as compared to 2022 was driven by higher than expected loss trends observed in our average cost per claim which we primarily attribute to increased medical costs driven by wage inflation and medical advancements. The increase also reflected the impact of reinsurance reinstatement premium, an increase in estimated losses within the AAD and, to a lesser extent, higher ULAE. See previous discussion on reinstatement premium under the heading "Revenues."

•Our current accident year net loss ratio in our Specialty P&C and Segregated Portfolio Cell Reinsurance segments remained relatively unchanged for 2023 as compared to 2022.

•As a result of our acquisition of NORCAL, our consolidated current accident year net loss ratio in 2022 was impacted by the purchase accounting amortization of the negative VOBA associated with NORCAL's assumed unearned premium of $4.9 million, which was recorded as a reduction to current accident year net losses. As of June 30, 2022, the negative VOBA was fully amortized which resulted in a 0.5 percentage point increase in 2023 as compared 2022.

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In 2023, our consolidated calendar year net loss ratio was higher than our consolidated current accident year net loss ratio due to the recognition of net unfavorable prior year reserve development, as shown in the previous table. For 2022, our consolidated calendar year net loss ratio was lower than our consolidated current accident year net loss ratio due to the recognition of net favorable prior year reserve development, as shown in the previous table. The following table shows the components of our consolidated net prior accident year reserve development:

Year Ended December 31
($ in thousands)20232022Change
Net favorable (unfavorable) reserve development$(13,978)$25,934$(39,912)(153.9%)
NORCAL Acquisition - Purchase Accounting Amortization8,33210,819(2,487)(23.0%)
Total net favorable (unfavorable) reserve development$(5,646)$36,753$(42,399)(115.4%)

•Specialty P&C: The loss environment in our HCPL line of business continues to be challenging in some jurisdictions, as claim costs are pressured by social inflation and higher than anticipated loss severity trends which started to emerge in the fourth quarter of 2022. We are monitoring the impact that these trends have on our open case reserves and prior year development. Net unfavorable reserve development was driven by the strengthening of case reserves related to four large claims in our HCPL line of business and unfavorable development associated with our Lloyd’s Syndicates operations, partially offset by net favorable development in other lines of business, predominately in our Medical Technology Liability line of business.

The contingent consideration associated with the NORCAL acquisition is dependent upon the after-tax development of NORCAL’s 2020 and prior accident year reserves from December 31, 2020 to December 31, 2023. In the fourth quarter of 2023, we recognized unfavorable development in NORCAL’s 2020 and prior accident year reserves which was entirely offset by favorable development recognized in NORCAL’s 2021 and 2022 accident year reserves since acquisition. While these adjustments to NORCAL’s reserves had no impact to our Specialty P&C segment’s net losses or net loss ratio, they contributed to the decrease in the fair value of the contingent consideration liability of $3.5 million in 2023 which was recorded as an offset to operating expenses in the Specialty P&C segment. See additional discussion on the Contingent Consideration in the Critical Accounting Estimates section under the heading "Contingent Consideration."

•Workers' Compensation Insurance: Net unfavorable development in 2023 reflected higher than expected loss trends observed in our average cost per claim, primarily in the 2022 accident year. We are monitoring the impact that these trends have on our open case reserves and prior year development. Net unfavorable development in 2023 also reflected higher than expected loss experience attributable to one large claim from the 1997 accident year.

•Segregated Portfolio Cell Reinsurance: Net favorable development in 2023 reflected overall favorable trends in claim closing patterns related to the workers' compensation business, primarily in accident years 2016 through 2021.

See the Segment Results sections that follow for additional information regarding each segment's reserve development.

Our consolidated and segment underwriting expense ratios were as follows:

Year Ended December 31
20232022Change
Underwriting Expense Ratio
Consolidated (1)30.8%29.9%0.9pts
Specialty P&C25.8%25.2%0.6pts
Workers' Compensation Insurance34.4%32.9%1.5pts
Segregated Portfolio Cell Reinsurance33.2%29.1%4.1pts
Corporate (2)3.5%3.4%0.1pts
(1) Consolidated underwriting expenses for 2022 include $1.9 million of transaction-related costs associated with our acquisition of NORCAL that are not included in a segment as we do not consider these costs in assessing the financial performance of any of our segments. We did not incur any transaction-related costs during 2023. See Note 16 of the Notes to Consolidated Financial Statements for a reconciliation of our segment results to our consolidated results.
(2) There are no net premiums earned associated with the Corporate segment. Ratios shown are the contribution of the Corporate segment to the consolidated ratio (Corporate operating expenses divided by consolidated net premiums earned).

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The change in our consolidated underwriting expense ratio for the year ended December 31, 2023 as compared to 2022 was primarily attributable to the following:

(In percentage points)Increase (Decrease) 2023 versus 2022
Estimated ratio increase (decrease) attributable to:
Change in Net Premiums Earned and DPAC amortization(1)0.4 pts
Tail Premium0.3 pts
Employee Retention Credit(0.4 pts)
One-Time Expenses(0.4 pts)
Contingent Consideration Remeasurement Adjustment(0.4 pts)
Transaction-related Costs(2)(0.2 pts)
All other, net1.6 pts
Increase in the underwriting expense ratio0.9 pts
(1) Excludes tail premium.
(2) See footnote 1 in the previous table for more information.

•Excluding the impact of the items specifically identified in the table above, our consolidated underwriting expense ratio increased by 1.6 percentage points in 2023 as compared to 2022 primarily driven by an increase in operating expenses in our Specialty P&C segment due to an increase in compensation-related expenses and, to a lesser extent, travel-related expenses, partially offset by a decrease in amounts accrued for performance-related incentive plans across all our operating segments.

•As shown in the previous table, our consolidated underwriting expense ratio for 2023 reflected the impact of the change in net premiums earned, excluding tail premium, in relation to the corresponding DPAC amortization resulting in a 0.4 percentage point increase in our ratio as compared to 2022 driven by the effect of reinsurance reinstatement premium recognized during the fourth quarter of 2023 in our Workers' Compensation Insurance segment (see previous discussion under the heading "Revenues").

•As shown in the previous table, our consolidated underwriting expense ratios for 2023 reflected the impact of the change in premium earned from tail policies as there is typically minimal associated acquisition costs.

•As shown in the previous table, our change in our consolidated underwriting expense ratio for 2023 also reflected the impact of a payroll tax refund of $3.8 million recognized in the first quarter of 2023 as a reduction to operating expenses in our Specialty P&C segment related to the employee retention credit available to us under the CARES Act, which resulted in a 0.4 percentage point decrease in the current period ratio. See additional discussion on the ERC in Note 1 of the Notes to Consolidated Financial Statements and previous discussion in the Liquidity section under the heading "Taxes."

•As shown in the previous table, the consolidated underwriting expense ratio for 2023 also reflects the prior year impact of one-time expenses of $3.9 million incurred in 2022 and accounted for a 0.4 percentage point decrease to our 2023 ratio. One-time expenses were mainly comprised of one-time bonuses, accelerated depreciation associated with a decommissioned IT system, employee severance charges and lease exit costs in our Specialty P&C segment.

•As shown in the previous table, our consolidated underwriting expense ratio for 2023 reflected the impact of the remeasurement of the contingent consideration liability associated with the NORCAL acquisition, which resulted in a 0.4 percentage point decrease in our 2023 ratio. As previously discussed, we recorded a reduction to operating expenses of $3.5 million related to the remeasurement of the contingent consideration liability associated with the NORCAL acquisition due to unfavorable development recognized on NORCAL's 2020 and prior accident year reserves in our Specialty P&C segment. See additional discussion on the Contingent Consideration in the Critical Accounting Estimates section under the heading "Contingent Consideration."

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Taxes

Our consolidated effective tax rates for the years ended December 31, 2023 and 2022 were as follows:

($ in thousands)Year Ended December 31
20232022Change
Income (loss) before income taxes$(39,149)$(6,216)$(32,933)(529.8%)
Income tax expense (benefit)(545)(5,814)5,26990.6%
Net income (loss)$(38,604)$(402)$(38,202)(9,503.0%)
Effective tax rate1.4%93.5%(92.1 pts)

We recognized an income tax benefit of $0.5 million and $5.8 million in 2023 and 2022, respectively. Our effective tax rate for the year ended December 31, 2023 was different from the statutory federal income tax rate of 21% primarily due to a $44.1 million goodwill impairment recognized in relation to the Workers' Compensation Insurance reporting unit during the third quarter of 2023, all of which is non-deductible. See further discussion on this goodwill impairment in Note 6 of the Notes to Consolidated Financial Statements. Our effective tax rate for the year ended December 31, 2022 differed from the statutory federal income tax rate of 21% primarily due to the benefit recognized from the tax credits transferred to us from our tax credit partnership investments. See further information on other notable items impacting our effective tax rate for the years ended December 31, 2023 and 2022 in the Segment Results - Corporate section that follows under the heading "Taxes."

Operating Ratio

Our operating ratio is our combined ratio, less our investment income ratio. This ratio provides the combined effect of underwriting profitability and investment income. Our operating ratio for the years ended December 31, 2023 and 2022 was as follows:

Year Ended December 31
20232022Change
Combined ratio112.7%105.3%7.4pts
Less: investment income ratio13.1%9.3%3.8pts
Operating ratio99.6%96.0%3.6pts

The primary drivers of the change in our operating ratio were as follows:

(In percentage points)Increase (Decrease) 2023 versus 2022
Estimated ratio increase (decrease) attributable to:
Change in Prior Accident Year Reserve Development4.0 pts
NORCAL Acquisition - Purchase Accounting Amortization(1)0.7 pts
Change in Net Premiums Earned and DPAC amortization(2)0.4 pts
Investment Results(3.8 pts)
Employee Retention Credit(0.4 pts)
Contingent Consideration Remeasurement Adjustment(0.4 pts)
Transaction-related Costs(0.2 pts)
All other, net3.3 pts
Increase in the operating ratio3.6 pts
(1) Includes the impact of purchase accounting amortization on current accident year net losses and prior accident year reserve development.
(2) Excludes tail premium.

Excluding the impact of the items specifically identified in the table above, our operating ratio in 2023 increased 3.3 percentage points as compared to 2022 driven by an increase in the consolidated combined ratio, the components of which are discussed in this section under the heading "Expenses" and further discussion in our Segment Operating Results sections that follow.

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Non-GAAP Financial Measures

Non-GAAP Operating Income (Loss)

Non-GAAP operating income (loss) is a financial measure that is widely used to evaluate performance within the insurance sector. In calculating Non-GAAP operating income (loss), we have excluded the effects of the items listed in the following table that do not reflect normal results. We believe Non-GAAP operating income (loss) presents a useful view of the performance of our insurance operations; however, it should be considered in conjunction with net income (loss) computed in accordance with GAAP.

The following table is a reconciliation of net income (loss) to Non-GAAP operating income (loss):

Year Ended December 31
(In thousands, except per share data)20232022
Net income (loss)$(38,604)$(402)
Items excluded in the calculation of Non-GAAP operating income (loss):
Net investment (gains) losses(1)(13,828)33,157
Net investment gains (losses) attributable to SPCs which no profit/loss is retained(2)2,925(2,138)
Transaction-related costs(3)1,862
Goodwill impairment44,110
Foreign currency exchange rate (gains) losses(4)2,993(2,022)
Non-operating income(5)(6,878)
Guaranty fund assessments (recoupments)57541
Pre-tax effect of exclusions29,37931,400
Tax effect, at 21%(6)1,894(8,087)
After-tax effect of exclusions31,27323,313
Non-GAAP operating income (loss)$(7,331)$22,911
Per diluted common share:
Net income (loss)$(0.73)$(0.01)
Effect of exclusions0.590.43
Non-GAAP operating income (loss) per diluted common share$(0.14)$0.42

(1) Net investment gains (losses) in 2023 and 2022 include gains of $5.0 million and $9.0 million, respectively, related to the change in the fair value of contingent consideration issued in connection with the NORCAL acquisition. We have excluded these adjustments as they do not reflect normal operating results. See further discussion around the contingent consideration in Note 2 and Note 8 of the Notes to Consolidated Financial Statements and discussion on our accounting policy in the Critical Accounting Estimates section under the heading "Contingent Consideration."

(2) Net investment gains (losses) on investments related to SPCs are recognized in our Segregated Portfolio Cell Reinsurance segment. SPC results, including any net investment gain or loss, that are attributable to external cell participants are reflected in the SPC dividend expense (income). To be consistent with our exclusion of net investment gains (losses) recognized in earnings, we are excluding the portion of net investment gains (losses) that is included in the SPC dividend expense (income) which is attributable to the external cell participants.

(3) Transaction-related costs associated with our acquisition of NORCAL. We are excluding these costs as they do not reflect normal operating results and are unique and non-recurring in nature.

(4) Foreign currency exchange rate gains (losses) relate to the impact of foreign exchange rate movements on foreign currency denominated loss reserves predominately associated with premium assumed from an international medical professional liability insured in our Specialty P&C segment. Our participation in this program has grown in recent years which has led to greater volatility in our results of operations even with nominal movements in exchange rates given the size of the reserve. We mitigate foreign exchange rate exposure on our Consolidated Balance Sheet by generally matching the currency and duration of associated investments to the corresponding loss reserves. In accordance with GAAP, the impact on the market value of available-for-sale fixed maturities due to changes in foreign currency exchange rates is reflected as a part of OCI. Conversely, the impact of changes in foreign currency exchange rates on loss reserves is reflected through net income (loss) as a component of other income. Therefore, we believe foreign currency exchange rate gains (losses) in our Consolidated Statements of Income and Comprehensive Income in isolation are not indicative of our operating performance.

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(5) Proceeds associated with the sale of our remaining ownership interest in the underwriting and operations entity associated with Syndicate 1729 to unrelated third parties recognized in other income in our Corporate segment. We are excluding these costs as they do not reflect normal operating results and are unique and non-recurring in nature.

(6) The 21% rate is the statutory tax rate associated with the taxable or tax deductible items listed above. Our statutory tax rate was applied to these items in calculating net income (loss), excluding the 2023 goodwill impairment which is not tax deductible. In addition, the 2023 and 2022 gains related to the change in the fair value of contingent consideration are non-taxable and therefore had no associated income tax impact. The taxes associated with the net investment gains (losses) related to SPCs in our Segregated Portfolio Cell Reinsurance segment are paid by the individual SPCs and are not included in our consolidated tax provision or net income (loss); therefore, both the net investment gains (losses) from our Segregated Portfolio Cell Reinsurance segment and the adjustment to exclude the portion of net investment gains (losses) included in the SPC dividend expense (income) in the table above are not tax effected.

Non-GAAP Operating ROE

Non-GAAP operating ROE is a financial measure that is calculated as Non-GAAP operating income (loss) for the period divided by the average of beginning and ending total GAAP shareholders’ equity. As previously discussed, in calculating Non-GAAP operating income (loss), we have excluded the effects of certain items that do not reflect normal results. Non-GAAP operating ROE measures the overall after-tax profitability of our insurance operations and shows how efficiently capital is being used; however, it should be considered in conjunction with ROE computed in accordance with GAAP. The following table is a reconciliation of ROE to Non-GAAP operating ROE for the years ended December 31, 2023 and 2022:

Year Ended December 31
20232022Change
ROE(3.5%)%(3.5pts)
Pre-tax effect of items excluded in the calculation of Non-GAAP operating ROE2.6%2.4%0.2pts
Tax effect, at 21%(1)0.2%(0.6%)0.8pts
Non-GAAP operating ROE(0.7%)1.8%(2.5pts)
(1) The 21% rate is the statutory tax rate associated with the taxable or tax deductible items. See further discussion in footnote 6 in this section under the heading "Non-GAAP Operating Income."

Non-GAAP operating ROE in 2023 decreased by 2.5 percentage points as compared to 2022 driven by unfavorable prior accident year reserve development and, to a lesser extent, an increase in the current accident year net loss ratio in our Workers' Compensation Insurance segment, partially offset by an increase in investment income due to higher average book yields as we continue to reinvest at higher rates as our portfolio matures. See previous discussions in this section under the headings "Executive Summary of Operations" and further discussion in our Segment Operating Results sections that follow.

Non-GAAP Adjusted Book Value per Share

Book value per share is calculated as total GAAP shareholders’ equity divided by the total number of common shares outstanding at the balance sheet date. This ratio measures the net worth of the Company to shareholders on a per share basis.

Non-GAAP adjusted book value per share is a Non-GAAP measure widely used within the insurance sector and is calculated as shareholders’ equity, excluding AOCI, divided by the total number of common shares outstanding at the balance sheet date. This Non-GAAP calculation measures the net worth of the Company to shareholders on a per share basis excluding AOCI to eliminate the temporary and potentially significant effects of fluctuations in interest rates on our fixed income portfolio; however, it should be considered in conjunction with book value per share computed in accordance with GAAP. The increase in interest rates led to significant unrealized holding losses on our available-for-sale fixed maturity investments resulting in volatility in AOCI in 2022 and 2023. See Note 12 of the Notes to Consolidated Financial Statements for additional information.

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The following table is a reconciliation of our book value per share to Non-GAAP adjusted book value per share at December 31, 2023 and December 31, 2022:

Book Value Per Share
Book Value Per Share at December 31, 2022$20.46
Less: AOCI Per Share(1)(5.53)
Non-GAAP Adjusted Book Value Per Share at December 31, 202225.99
Increase (decrease) to Non-GAAP Adjusted Book Value Per Share during the year ended December 31, 2023 attributable to:
Dividends paid(0.05)
Cumulative repurchase of shares(2)0.59
Net income (loss)(3)(0.76)
Other(4)0.06
Non-GAAP Adjusted Book Value Per Share at December 31, 202325.83
Add: AOCI Per Share(1)(4.01)
Book Value Per Share at December 31, 2023$21.82
(1) Primarily the impact of accumulated unrealized investment gains (losses) on our available-for-sale fixed maturity investments. See Note 12 of the Notes to Consolidated Financial Statements for additional information.
(2) Represents the impact of our repurchase of 3.1 million common shares, conducted through a series of 10b5-1 stock repurchase plans during 2023. See previous discussion in the Liquidity section under the heading "Treasury Shares" for additional information.
(3) Includes the $44.1 million goodwill impairment associated with the Workers' Compensation Insurance segment, which accounted for $0.87 of the decrease in book value per share. See further discussion on the goodwill impairment under the heading "Goodwill / Intangibles" in the Critical Accounting Estimates section and Note 6 of the Notes to Consolidated Financial Statements.
(4) Includes the impact of share-based compensation.

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Segment Results - Specialty Property & Casualty

Our Specialty P&C segment focuses on professional liability insurance and medical technology liability insurance as discussed in Note 16 of the Notes to Consolidated Financial Statements. As previously discussed under the heading "ProAssurance Overview," we reorganized our segment reporting in the third quarter of 2023. As a result, the underwriting results from our participation in the results of Syndicate 1729 and Syndicate 6131 at Lloyd's of London which were previously reported in our Lloyd’s Syndicates segment are now reported in our Specialty P&C segment. We normally report results from our involvement in Lloyd's Syndicates on a quarter lag, except when information is available that is material to the current period. All prior period segment information has been recast to conform to the current period presentation and the segment reorganization had no impact on previously reported consolidated financial results. See further information regarding the segment reorganization in Note 16 of the Notes to Consolidated Financial Statements.

Segment results reflected pre-tax underwriting profit or loss from these insurance lines and included the amortization of certain purchase accounting adjustments. Segment results for the year ended December 31, 2022 exclude transaction-related costs associated with our acquisition of NORCAL as we do not consider these costs in assessing the financial performance of the segment. We did not incur any transaction-related costs during the year ended December 31, 2023. Segment results included the following:

Year Ended December 31
($ in thousands)20232022Change
Net premiums written$762,580$784,020$(21,440)(2.7%)
Net premiums earned$755,817$793,400$(37,583)(4.7%)
Other income4,6955,122(427)(8.3%)
Net losses and loss adjustment expenses(624,809)(626,045)1,236(0.2%)
Underwriting, policy acquisition and operating expenses(195,303)(199,809)4,506(2.3%)
Segment results$(59,600)$(27,332)$(32,268)(118.1%)
Net loss ratio82.7%78.9%3.8pts
Underwriting expense ratio25.8%25.2%0.6pts

Premiums Written

Changes in our premium volume within our Specialty P&C segment are generally driven by three primary factors: (1) the amount of new business written, (2) our retention of existing business and (3) the premium charged for business that is renewed, which is affected by rates charged and by the amount and type of coverage an insured chooses to purchase. In addition, premium volume may periodically be affected by shifts in the timing of renewals between periods.

The medical professional liability market, which accounts for a majority of the revenues in this segment, remains challenging as physicians continue joining hospitals or larger group practices and, therefore, are no longer purchasing individual or group policies in the standard market. In addition, some competitors have chosen to compete primarily on price. Both factors may impact our ability to write new business and retain existing business. Furthermore, the insurance and reinsurance markets have historically been cyclical, characterized by extended periods of intense price competition and other periods of reduced capacity. The medical professional liability market has been particularly affected by these cycles. Underwriting cycles are driven, among other reasons, by excess capacity available to compete for the business. Changes in the frequency and severity of losses may also affect the cycles of the insurance and reinsurance markets significantly. During “soft markets” where price competition is high and underwriting profits are poor, growth and retention of business become challenging which may result in reduced premium volumes.

Gross, ceded and net premiums written were as follows:

Year Ended December 31
($ in thousands)20232022Change
Gross premiums written$835,430$856,861$(21,431)(2.5%)
Less: Ceded premiums written72,85072,8419%
Net premiums written$762,580$784,020$(21,440)(2.7%)

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Gross Premiums Written

Gross premiums written by component were as follows:

Year Ended December 31
($ in thousands)20232022Change
Professional Liability
HCPL
Standard Physician(1)$419,726$444,477$(24,751)(5.6%)
Specialty
Custom Physician(2)(10)88,08281,2626,8208.4%
Hospitals and Facilities(3)(10)74,86768,9815,8868.5%
Senior Care(4)(10)7,1296,35477512.2%
Reinsurance assumed(5)47,23543,4493,7868.7%
Total Specialty217,313200,04617,2678.6%
Total HCPL637,039644,523(7,484)(1.2%)
Small Business Unit(6)99,360102,524(3,164)(3.1%)
Tail Coverages(7)(10)34,87847,655(12,777)(26.8%)
Total Professional Liability771,277794,702(23,425)(2.9%)
Medical Technology Liability(8)44,58141,0653,5168.6%
Lloyd's Syndicates(9)19,57220,233(661)(3.3%)
Other861(861)nm
Total Gross Premiums Written$835,430$856,861$(21,431)(2.5%)

(1) Standard Physician premium was our greatest source of premium revenues in 2023 and 2022 and is comprised of twelve month term policies and, for 2022, three month term policies. The decrease in Standard Physician premium for 2023 as compared to 2022 was driven by retention losses and, to a lesser extent, the impact of the conversion of three month term policies to twelve month term policies in the prior year period, partially offset by an increase in renewal pricing and new business written, including the addition of six policies totaling $9.1 million. Retention losses during 2023 generally reflect our pursuit of rate adequacy in a competitive market where other carriers may not have the same objectives, appreciate the rate need, or are attempting to gain market share despite near term underwriting losses (see additional discussion in Part I Item 1. Business under the heading "Competition"). Renewal pricing increases during 2023 reflect the rising loss cost environment and new business written reflects the competitive market conditions.

(2) Custom Physician premium includes large physician groups, multi-state physician groups and non-standard physicians and is written primarily on an excess and surplus lines basis. The increase in Custom Physician premium in 2023 as compared to 2022 was driven by new business written, including the addition of five policies totaling $6.2 million during the 2023 and, to a lesser extent, an increase in renewal pricing, partially offset by retention losses. Renewal pricing increases for 2023 reflect pricing actions taken in response to a rising loss cost environment and new business written reflects the competitive market conditions. The retention losses in our Custom Physician book in 2023 reflects our focus on underwriting discipline, the loss of a $2.2 million policy due to price competition and the loss of a $2.8 million policy due to the insured moving to a captive arrangement.

(3) Hospitals and Facilities premium (which includes hospitals, surgery centers and miscellaneous medical facilities) increased in 2023 as compared to 2022 driven by new business written, including the addition of two policies totaling $6.9 million and, to a lesser extent, an increase in renewal pricing, partially offset by retention losses. Renewal pricing increases in 2023 reflect rate increases and contract modifications that we believe are appropriate given the current loss environment and new business written reflects the competitive market conditions. Retention losses in 2023 were largely attributable to the loss of a $4.6 million policy due to the insured entering into a captive arrangement during the first quarter of 2023, which resulted in a decrease to our Specialty retention rate of 3.0 percentage points.

(4) Senior Care premium includes facilities specializing in long term residential care primarily for the elderly ranging from independent living through skilled nursing. Our Senior Care premium increased in 2023 as compared to 2022 driven by new business written and, to a lesser extent, an increase in renewal pricing, partially offset by retention losses.

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(5) We offer custom alternative risk solutions including assumed reinsurance. The increase in premium in 2023 reflected an increase in premiums assumed on a quota share basis through a strategic partnership in place since 2016 with an international medical professional liability insurer and, to a lesser extent, an increase in premiums assumed through a reinsurance arrangement with a hospital captive insurance company.

(6) Our Small Business Unit is comprised of premium associated with podiatrists, legal professionals, dentists and chiropractors. Our Small Business Unit premium decreased in 2023 as compared to 2022 driven by retention losses, partially offset by an increase in renewal pricing and, to a lesser extent, new business written. The increase in renewal pricing in 2023 was primarily the result of an increase in the rate charged for certain renewed policies in select states.

(7) We offer extended reporting endorsement or "tail" coverage to insureds who discontinue their claims-made coverage with us, and we also periodically offer tail coverage through stand-alone policies. Tail coverage premiums are generally 100% earned in the period written because the policies insure only incidents that occurred in prior periods and generally are not cancellable. The amount of tail coverage premium written can vary significantly from period to period.

(8) Our Medical Technology Liability business is marketed throughout the U.S.; coverage is offered on a primary and excess basis, within specified limits, to manufacturers and distributors of medical technology and life sciences products including entities conducting human clinical trials. In addition to the previously listed factors that affect our premium volume, our Medical Technology Liability premium is also impacted by the sales volume of insureds. Our Medical Technology Liability premium increased in 2023 as compared to 2022 driven by new business written, timing differences primarily related to the prior year renewal of one policy and, to a lesser extent, an increase in renewal pricing, partially offset by retention losses. Renewal pricing increases in 2023 are primarily due to changes in the sales volume and changes in exposure of certain insureds. Retention losses in 2023 are primarily attributable to insureds no longer needing coverage, insureds no longer in business, an increase in competition on terms and pricing, cancellation for non-payment, as well as merger activity within the industry.

(9) Our Lloyd's Syndicates business includes the results from our participation in Syndicate 1729 and Syndicate 6131 at Lloyd's of London. For each of the 2023 and 2022 underwriting years our participation in the results of Syndicate 1729 is approximately 5%. Effective January 1, 2022, Syndicate 6131 ceased underwriting on a quota share basis with Syndicate 1729. Due to the quarter lag, our ceased participation in Syndicate 6131 was not reflected in our results until the second quarter of 2022. Our Lloyd’s Syndicates premium decreased during 2023 as compared to 2022 driven by our ceased participation in Syndicate 6131 for the 2022 underwriting year, partially offset by volume increases on renewal business and renewal pricing increases, primarily on property insurance and casualty coverages.

(10) Certain components of our gross premiums written include alternative market premiums. We currently cede either all or a portion of the alternative market premium, net of reinsurance, to three SPCs of our wholly owned Cayman Islands reinsurance subsidiary, Inova Re, which is reported in our Segregated Portfolio Cell Reinsurance segment (see further discussion in the Ceded Premiums Written section that follows). The portion not ceded to the SPCs is retained within our Specialty P&C segment.

Year Ended December 31
($ in millions)20232022Change
Custom Physician$2.1$2.0$0.15.0%
Hospitals and Facilities0.1(0.1)nm
Senior Care4.54.8(0.3)(6.3%)
Tail Coverages0.14.9(4.8)(98.0%)
Total$6.7$11.8$(5.1)(43.2%)

Alternative market gross premiums written decreased in 2023 as compared to 2022 driven by the prior year impact of tail coverage, primarily related to one program in which we do not participate in the underwriting results.

We are committed to a rate structure that will allow us to fulfill our obligations to our insureds while generating competitive long-term returns for our shareholders. Our pricing continues to be based on expected losses as indicated by our historical loss data and available industry loss data. In recent years, this practice has resulted in rate increases and we anticipate further rate increases due to indications of increasing projected loss severity. Additionally, the pricing of our business includes the effects of filed rates, surcharges and discounts. Renewal pricing reflects changes in our exposure base, deductibles, self-insurance retention limits and other policy terms and conditions. See further explanation of changes in renewal pricing above under the heading "Gross Premiums Written".

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The change in renewal pricing for our Specialty P&C segment, including by major component, was as follows:

Year Ended December 31
2023
Specialty P&C segment*6%
HCPL
Standard Physician6%
Specialty10%
Total HCPL7%
Small Business Unit4%
Medical Technology Liability1%
* Excludes Lloyd's Syndicates premium.

New business written by major component on a direct basis was as follows:

Year Ended December 31
(In millions)20232022
HCPL
Standard Physician$22.6$9.8
Specialty31.219.1
Total HCPL53.828.9
Small Business Unit3.33.8
Medical Technology Liability7.74.6
Total$64.8$37.3

For our Specialty P&C segment, we calculate retention as annualized renewed premium divided by all annualized premium subject to renewal. Retention is affected by a number of factors. We may lose insureds to competitors or to alternative insurance mechanisms such as risk retention groups, captive arrangements or self-insurance entities (often when physicians join hospitals or large group practices) or due to pricing or other issues. We may choose not to renew an insured as a result of our underwriting evaluation. Insureds may also terminate coverage because they have left the practice of medicine for various reasons, principally for retirement, death or disability, but also for personal reasons. See further explanation of changes in retention above under the heading "Gross Premiums Written".

Retention for our Specialty P&C segment, including by major component, was as follows:

Year Ended December 31
20232022
Specialty P&C segment*85%84%
HCPL
Standard Physician87%88%
Specialty78%69%
Total HCPL85%82%
Small Business Unit89%91%
Medical Technology Liability82%90%
*Excludes Lloyd's Syndicates premium.

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Ceded Premiums Written

Ceded premiums represent the amounts owed to our reinsurers for their assumption of a portion of our losses. Our HCPL and Medical Technology Liability excess of loss reinsurance arrangements renew annually on October 1. For the October 1, 2023 renewal, both our HCPL and Medical Technology Liability treaties renewed at a higher rate than the previous treaties and we continue to generally retain the first $2 million in risk insured by us and cede coverages in excess of this amount. For our HCPL coverages in excess of $2 million, we generally retain from 9% to 9.5% of the next $24 million of risk which increased from a retention of 0% to 5% in the expiring treaty. For our Medical Technology Liability treaty, we do not retain any of the next $8 million of risk for coverages in excess of $2 million. All other material terms were consistent with the expiring treaties.

We pay our reinsurers a ceding premium in exchange for their accepting the risk, and in certain of our excess of loss arrangements, the ultimate amount of which is determined by the loss experience of the business ceded, subject to certain minimum and maximum amounts. Given the length of time that it takes to resolve our claims, many years may elapse before all losses recoverable under a reinsurance arrangement are known. As a part of the process of estimating our loss reserve we also make estimates regarding the amounts recoverable under our reinsurance arrangements. As a result, we may have an adjustment to our estimate of expected losses and associated recoveries for prior year ceded losses under certain loss sensitive reinsurance agreements. Any changes to estimates of premiums ceded related to prior accident years are fully earned in the period the changes in estimates occur.

Ceded premiums written were as follows:

Year Ended December 31
($ in thousands)20232022Change
Excess of loss reinsurance arrangements (1)$40,191$38,005$2,1865.8%
Other shared risk arrangements (2)20,89319,0491,8449.7%
Premium ceded to SPCs (3)5,64010,902(5,262)(48.3%)
Other ceded premiums written8,5527,71383910.9%
Adjustment to premiums owed under reinsurance agreements, prior accident years, net (4)(2,426)(2,828)402(14.2%)
Total ceded premiums written$72,850$72,841$9%

(1)We generally reinsure risks under our excess of loss reinsurance arrangements pursuant to which the reinsurers agree to assume all or a portion of all risks that we insure above our individual risk retention levels. Premium due to reinsurers is based on a rate factor applied to gross premiums written subject to cession under the arrangement. The increase in ceded premiums written under our excess of loss reinsurance arrangements in 2023 as compared to 2022 was driven by an increase in the overall volume of gross premiums written subject to cession and the impact of prior year adjustments on certain of our reinsurance arrangements reaching maximum limits eligible for cession on certain treaty years.

(2)We have entered into various shared risk arrangements, including quota share, fronting and captive arrangements, with certain large healthcare systems and other insurance entities. While we cede a large portion of the premium written under these arrangements, they provide us an opportunity to grow net premium through strategic partnerships. Ceded premiums written under these arrangements increased in 2023 as compared to 2022 driven by an increase in premium ceded under a particular arrangement with a hospital group and an existing insured entering into an arrangement during the first quarter of 2023.

(3)As previously discussed, as a part of our alternative market solutions, all or a portion of certain healthcare premium written is ceded to SPCs in our Segregated Portfolio Cell Reinsurance segment under either excess of loss or quota share reinsurance agreements, depending on the structure of the individual program. See the Segment Results - Segregated Portfolio Cell Reinsurance section for further discussion on the cession to the SPCs from our Specialty P&C segment. Premiums ceded to SPCs in 2023 decreased as compared to 2022 driven by the prior year impact of tail coverage, primarily related to one program in which we do not participate in the underwriting results.

(4)Given the length of time that it takes to resolve our claims, many years may elapse before all losses recoverable under a reinsurance arrangement are known. As a part of the process of estimating our loss reserve we also make estimates regarding the amounts recoverable under our reinsurance arrangements. As previously discussed, the premiums ultimately ceded under certain of our swing rated excess of loss reinsurance arrangements are subject to the losses ceded under the arrangements. As part of the review of our reserves for 2023 and 2022, we recorded a net decrease in our estimate of ceded premiums owed to reinsurers due to a decrease in our estimate of expected losses and associated recoveries for prior year ceded losses. Changes to estimates of premiums ceded related to prior accident years are fully earned in the period the changes in estimates occur.

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Ceded Premiums Ratio

As shown in the table below, our ceded premiums ratio was affected in both 2023 and 2022 by revisions to our estimate of premiums owed to reinsurers related to coverages provided in prior accident years. The ceded premiums ratio was as follows:

Year Ended December 31
20232022Change
Ceded premiums ratio8.7%8.5%0.2pts
Less the effect of adjustments in premiums owed under reinsurance agreements, prior accident years (as previously discussed)(0.3%)(0.3%)pts
Ratio, current accident year9.0%8.8%0.2pts

The above table reflects ceded premiums written, excluding the effect of prior year ceded premium adjustments, as previously discussed, as a percent of gross premiums written. Our current accident year ceded premiums ratio remained relatively unchanged for 2023 as compared to 2022.

Net Premiums Earned

Net premiums earned consist of gross premiums earned less the portion of earned premiums that we cede to our reinsurers for their assumption of a portion of our losses. Because premiums are generally earned pro rata over the entire policy period, fluctuations in premiums earned tend to lag those of premiums written. The majority of our policies carry a term of one year; however, some of our Medical Technology Liability policies have a multi-year term. Tail coverage premiums are generally 100% earned in the period written because the policies insure only incidents that occurred in prior periods and are not cancellable. Retroactive coverage premiums are 100% earned at the inception of the contract, as all of the associated underlying loss events occurred in the past. Additionally, any ceded premium changes due to changes to estimates of premiums owed under reinsurance agreements for prior accident years are fully earned in the period of change.

Net premiums earned were as follows:

Year Ended December 31
($ in thousands)20232022Change
Gross premiums earned$826,907$861,986$(35,079)(4.1%)
Less: Ceded premiums earned71,09068,5862,5043.7%
Net premiums earned$755,817$793,400$(37,583)(4.7%)

Gross premiums earned decreased in 2023 as compared to 2022 driven by the pro rata effect of a decrease in the volume of written premium during the preceding twelve months due to competitive market conditions, our process of evaluating the NORCAL book of business and implementing ProAssurance's underwriting strategies and, to a lesser extent, our ceased participation in Syndicate 6131 for the 2022 underwriting year.

Ceded premiums earned during both 2023 and 2022 included prior accident year ceded premium adjustments under swing rated reinsurance agreements (see previous discussion in footnote 4 under the heading "Ceded Premiums Written"). After removing the effect of the prior accident year ceded premium adjustment from both years, ceded premiums earned increased by $2.1 million in 2023 as compared to 2022 driven by the pro rata effect of an increase in premium ceded under our excess of loss arrangements during the preceding twelve months.

Losses and Loss Adjustment Expenses

The determination of calendar year losses involves the actuarial evaluation of incurred losses for the current accident year and the actuarial re-evaluation of incurred losses for prior accident years.

Accident year refers to the accounting period in which the insured event becomes a liability of the insurer. For claims-made policies, which represent the majority of the premiums written in our Specialty P&C segment, the insured event generally becomes a liability when the event is first reported to us and the policy that is in effect at that time covers the claim. For occurrence policies, the insured event becomes a liability when the event takes place even though the claim may be reported to us at a later date. For retroactive coverages, the insured event becomes a liability at inception of the underlying contract. We believe that measuring losses on an accident year basis is the best measure of the underlying profitability of the premiums earned in that period, since it associates policy premiums earned with the estimate of the losses incurred related to those policy premiums.

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The following table summarizes calendar year net loss ratios for our Specialty P&C segment by separating losses between the current accident year and all prior accident years. The net loss ratios for our Specialty P&C segment were as follows:

Net Loss Ratios (1)
Year Ended December 31
20232022Change
Calendar year net loss ratio82.7%78.9%3.8pts
Less impact of prior accident years on the net loss ratio0.1%(2.8%)2.9pts
Current accident year net loss ratio(2)82.6%81.7%0.9pts

(1)Net losses, as specified, divided by net premiums earned.

(2)For the year ended December 31, 2023, our current accident year net loss ratio (as shown in the table above), increased 0.9 percentage points as compared to 2022. The change in our current accident year net loss ratio was primarily attributable to the following:

(In percentage points)Increase (Decrease) 2023 versus 2022
Estimated ratio increase (decrease) attributable to:
Lloyd's Syndicates0.5 pts
NORCAL Acquisition - Purchase Accounting Amortization0.6 pts
All other, net(0.2 pts)
Increase in current accident year net loss ratio0.9 pts

•Excluding the impact of the items specifically identified in the table above, our current accident year net loss ratio remained relatively unchanged as compared to 2022. While we increased certain expected loss ratios in our HCPL line of business during the first quarter of 2023, this was more than offset by changes in the mix of business. We continue to observe higher than anticipated loss severity trends in select jurisdictions that started to emerge in the fourth quarter of 2022 and, as a result, we increased certain expected loss ratios in our HCPL line of business during the first quarter of 2023.

•As a result of our acquisition of NORCAL, our current accident year net loss ratio in 2022 was impacted by the purchase accounting amortization of $4.9 million related to the negative VOBA associated with NORCAL's assumed unearned premium which was recorded as a reduction to current accident year net losses. As of June 30, 2022, the negative VOBA was fully amortized which resulted in a 0.6 percentage point increase in the year ended December 31, 2023 ratio as compared to the prior year period.

We re-evaluate our previously established reserve each quarter based upon the most recently completed actuarial analysis supplemented by any new analysis, information or trends that have emerged since the date of that study. We also take into account currently available industry trend information.

The following table shows the components of our net prior accident year reserve development:

Year Ended December 31
($ in thousands)20232022Change
Net favorable (unfavorable) reserve development$(8,660)$11,667$(20,327)(174.2%)
NORCAL Acquisition - Purchase Accounting Amortization8,33210,819(2,487)(23.0%)
Total net favorable (unfavorable) reserve development$(328)$22,486$(22,814)(101.5%)

2023: The loss environment in our HCPL line of business continues to be challenging in some jurisdictions, as claim costs are pressured by social inflation and higher than anticipated loss severity trends which started to emerge in the fourth quarter of 2022. We are monitoring the impact that these trends have on our open case reserves and prior year development. Net unfavorable reserve development was driven by the strengthening of case reserves related to four large claims in our HCPL line of business (-$10.1 million) and unfavorable development associated with our Lloyd’s Syndicates operations (-$3.1 million), partially offset by net favorable development in other lines of business, predominately in our Medical Technology Liability line of business.

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The contingent consideration associated with the NORCAL acquisition is dependent upon the after-tax development of NORCAL’s 2020 and prior accident year reserves from December 31, 2020 to December 31, 2023. In the fourth quarter of 2023, we recognized unfavorable development in NORCAL’s 2020 and prior accident year reserves which was entirely offset by favorable development recognized in NORCAL’s 2021 and 2022 accident year reserves since acquisition. While these adjustments to NORCAL’s reserves had no impact to the segment’s net losses or net loss ratio, they contributed to the decrease in the fair value of the contingent consideration liability of $3.5 million in 2023 which was recorded as an offset to operating expenses in the segment. See further discussion that follows under the heading “Underwriting, Policy Acquisition and Operating Expenses.”

2022: Net favorable reserve development was driven by favorable development recognized in our Medical Technology Liability line of business (+$5.0 million), favorable development recognized in Small Business Unit line of business (+4.0 million), the remaining decrease to our previous IBNR reserve for COVID-19 (+$9.0 million) and net favorable development in our HCPL line of business (+$5.0 million), partially offset by unfavorable development associated with our Lloyd’s Syndicates operations (-$7.3 million) and increase to our reserve for potential ECO/XPL claims (-$4.0 million).

A detailed discussion of factors influencing our recognition of loss development is included in our Critical Accounting Estimates section under the heading "Reserve for Losses and Loss Adjustment Expenses." Assumptions used in establishing our reserve are regularly reviewed and updated by management as new data becomes available. Any adjustments necessary are reflected in the then current operations. Due to the size of our reserve, even a small percentage adjustment to the assumptions can have a material effect on our results of operations for the period in which the change is made, as was the case in both 2023 and 2022.

Underwriting, Policy Acquisition and Operating Expenses

Our Specialty P&C segment underwriting, policy acquisition and operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20232022Change
DPAC amortization$101,691$97,757$3,9344.0%
Management fees3,8944,763(869)(18.2%)
Other underwriting and operating expenses89,71897,289(7,571)(7.8%)
Total$195,303$199,809$(4,506)(2.3%)

DPAC amortization increased in 2023 as compared to 2022 primarily due to an increase in compensation-related expenses due to an increase in headcount and, to a lesser extent, an increase in agency commissions. In addition, DPAC amortization for 2022 reflected the impact of purchase accounting from the NORCAL acquisition which resulted in DPAC amortization being approximately $1.0 million lower than would have otherwise been recognized for the period due to the application of GAAP purchase accounting rules. Under these purchase accounting rules, the capitalized policy acquisition costs for NORCAL policies written prior to the acquisition date were written off through purchase accounting on May 5, 2021 rather than being expensed pro rata over the remaining term of the associated policies.

Management fees are charged pursuant to a management agreement by the Corporate segment to the core domestic operating subsidiaries within our Specialty P&C segment for services provided based on the extent to which services are provided to the subsidiary and the amount of premium written by the subsidiary. While the terms of the management agreement were generally consistent between 2023 and 2022, fluctuations in the amount of premium written by each subsidiary can result in corresponding variations in the management fee charged to each subsidiary during a particular period.

Other underwriting and operating expenses decreased in 2023 as compared to 2022 primarily attributable to the following:

•Certain one-time expenses of $3.9 million incurred during 2022 and a decrease in amounts accrued for performance-related incentive plans in 2023 due to the decline of the related performance metrics. One-time expenses during 2022 were mainly comprised of one-time bonuses, accelerated depreciation associated with a decommissioned IT system, employee severance charges and lease exit costs.

•A claim for a payroll tax refund of $3.8 million recognized in 2023 as a reduction to operating expenses related to the employee retention credit available to us under the CARES Act. See additional discussion on the ERC in Note 1 of the Notes to Consolidated Financial Statements and previous discussion in the Liquidity section under the heading "Taxes."

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•A reduction to operating expenses of $3.5 million in 2023 related to the remeasurement of the contingent consideration liability associated with the NORCAL acquisition due to unfavorable development recognized on NORCAL's 2020 and prior accident year reserves during the year. See additional discussion on the contingent consideration in the previous section under the heading "Losses and Loss Adjustment Expenses" and in the Critical Accounting Estimates section under the heading "Contingent Consideration."

•The decrease in other underwriting and operating expenses was partially offset by an increase in compensation-related expenses in 2023 due to organizational structure changes and the movement of certain employees from the Corporate segment to the Specialty P&C segment beginning in the third quarter of 2022.

Underwriting Expense Ratio (the Expense Ratio)

Our expense ratio for the Specialty P&C segment was as follows:

Year Ended December 31
20232022Change
Underwriting expense ratio25.8%25.2%0.6pts

The change in our expense ratio in 2023 as compared to 2022 was primarily attributable to the following:

(In percentage points)Increase (Decrease) 2023 versus 2022
Estimated ratio increase (decrease) attributable to:
Change in Net Premiums Earned and DPAC amortization0.7 pts
One-Time Expenses(0.5 pts)
Employee Retention Credit(0.5 pts)
Contingent Consideration Remeasurement Adjustment(0.5 pts)
All other, net1.4 pts
Increase in the underwriting expense ratio0.6 pts

Excluding the impact of the items specifically identified in the table above, our expense ratio increased in 2023 by 1.4 percentage points as compared to 2022 primarily driven by higher compensation-related expenses due to the aforementioned organizational structure changes in 2022 and, to a lesser extent, an increase in travel-related expenses, partially offset by a decrease in amounts accrued for performance-related incentive plans.

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Segment Results - Workers' Compensation Insurance

Our Workers' Compensation Insurance segment includes workers' compensation products provided to employers generally with 1,000 or fewer employees, as discussed in Note 16 of the Notes to Consolidated Financial Statements. Workers' compensation products offered include guaranteed cost policies, policyholder dividend policies, retrospectively-rated policies, deductible policies and alternative market programs. Alternative market programs include services related to program design, fronting, claims administration, risk management, SPC rental, asset management and SPC management services. Alternative market program premiums are 100% ceded to either the SPCs within our Segregated Portfolio Cell Reinsurance segment or captive insurers unaffiliated with ProAssurance for two programs. Our Workers' Compensation Insurance segment results reflect pre-tax underwriting profit or loss from these workers' compensation products, exclusive of investment results, which are included in our Corporate segment. Segment results included the following:

Year Ended December 31
($ in thousands)20232022Change
Net premiums written$162,285$160,760$1,5250.9%
Net premiums earned$160,034$166,371$(6,337)(3.8%)
Other income1,8542,201(347)(15.8%)
Net losses and loss adjustment expenses(139,322)(111,407)(27,915)25.1%
Underwriting, policy acquisition and operating expenses(55,061)(54,737)(324)0.6%
Segment results$(32,495)$2,428$(34,923)(1,438.3%)
Net loss ratio87.1%67.0%20.1 pts
Underwriting expense ratio34.4%32.9%1.5 pts

Premiums Written

Our workers’ compensation premium volume is driven by five primary factors: (1) the amount of new business written, (2) retention of our existing book of business, (3) premium rates charged on our renewal book of business, (4) changes in payroll exposure and (5) audit premium.

Gross, ceded and net premiums written were as follows:

Year Ended December 31
($ in thousands)20232022Change
Gross premiums written$246,857$247,132$(275)(0.1%)
Less: Ceded premiums written84,57286,372(1,800)(2.1%)
Net premiums written$162,285$160,760$1,5250.9%

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Gross Premiums Written

Gross premiums written by product were as follows:

Year Ended December 31
($ in thousands)20232022Change
Traditional business:
Guaranteed cost$137,088$135,847$1,2410.9%
Policyholder dividend22,82921,5471,2825.9%
Deductible5,0614,7053567.6%
Retrospective2,7493,123(374)(12.0%)
Other6,3767,286(910)(12.5%)
Change in EBUB estimate2,9001,4501,450100.0%
Total traditional business(1)177,003173,9583,0451.8%
Alternative market business(2)69,85473,174(3,320)(4.5%)
Total$246,857$247,132$(275)(0.1%)

(1) Gross premiums written in our traditional business reflect the continuation of competitive workers' compensation market conditions, including the impact of compounded state loss cost reductions in our core operating territories. For the year ended December 31, 2023, new business written and audit premium, including changes in our carried EBUB estimate, drove the increase in gross written premium, partially offset by lower renewal premium. New business writings in 2023 increased to $22.0 million as compared to $14.1 million in 2022. Policy audits processed in 2023 resulted in audit premium billed to policyholders totaling $9.1 million as compared to $8.2 million in 2022. We increased our carried EBUB estimate in 2023 based on recent audit trends and our expectation of higher levels of audit premium due to wage inflation. Renewal premium results in 2023 reflected premium retention of 83% and rate decreases of 5%, partially offset by an increase in payroll exposure.

(2) A majority of alternative market premiums are ceded to SPCs in our Segregated Portfolio Cell Reinsurance segment. See further discussion on alternative market gross premiums written in our Segment Operating Results - Segregated Portfolio Cell Reinsurance section under the heading "Gross Premiums Written" that follows. We retained 100% of the twenty-four workers' compensation alternative market programs that were up for renewal during the year ended December 31, 2023.

New business, audit premium, renewal retention and renewal price changes for our traditional business and the alternative market business are shown in the table below:

Year Ended December 31
20232022
($ in millions)Traditional BusinessAlternative Market BusinessSegment ResultsTraditional BusinessAlternative Market BusinessSegment Results
New business$22.0$4.2$26.2$14.1$3.6$17.7
Audit premium (excluding EBUB)$9.1$3.6$12.7$8.2$5.4$13.6
Retention rate (1)83%89%85%82%87%83%
Change in renewal pricing (2)(5%)(5%)(5%)(5%)(4%)(5%)
(1) We calculate our workers' compensation retention rate as annualized expiring renewed premium divided by all annualized expiring premium subject to renewal. Our retention rate can be impacted by various factors, including price or other competitive issues, insureds being acquired, or a decision not to renew based on our underwriting evaluation.
(2) The pricing of our business includes an assessment of the underlying policy exposure and market conditions. We continue to base our pricing on expected losses, as indicated by our historical loss data.

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Ceded Premiums Written

Ceded premiums written were as follows:

Year Ended December 31
($ in thousands)20232022Change
Premiums ceded to SPCs(1)$64,619$68,035$(3,416)(5.0%)
Premiums ceded to external reinsurers(2)16,56414,1772,38716.8%
Premiums ceded to unaffiliated captive insurers(1)5,2355,139961.9%
Change in return premium estimate under external reinsurance(3)(667)297(964)(324.6%)
Estimated revenue share under external reinsurance(4)(1,179)(1,276)97(7.6%)
Total ceded premiums written$84,572$86,372$(1,800)(2.1%)
(1) Represents alternative market business that is ceded under 100% quota share reinsurance agreements to the SPCs in our Segregated Portfolio Cell Reinsurance segment. Premiums ceded to unaffiliated captive insurers represent alternative market business for two programs that are ceded under 100% quota share reinsurance agreements. See further discussion on alternative market gross premiums written in our Segment Operating Results - Segregated Portfolio Cell Reinsurance section under the heading "Gross Premiums Written" that follows.
(2) Under our external reinsurance treaty for traditional business, we retain the first $0.5 million in risk insured by us and cede losses in excess of this amount on each loss occurrence, subject to an AAD, equal to 3.5% of subject earned premium for the treaty years effective May 1, 2023 and 2022. Premiums ceded under our traditional reinsurance treaty are based on premiums earned during the treaty period. Our ceded premium increased for the year ended December 31, 2023 as compared to the same period in 2022, reflecting higher reinsurance rates at our May 1, 2023 renewal and reinstatement premium of $1.6 million that was recognized during the fourth quarter of 2023 related to a reserve increase on a prior year reinsured claim.
(3) Changes in the return premium estimate reflect adjustments to our estimate of expected future recovery of ceded premium based on the underlying loss experience of our reinsurance treaties that include a provision for return premium. Increases in reinsured losses reduce the return premium estimate, while decreases in reinsured losses increase the return premium estimate.
(4) We are party to a revenue sharing agreement with our reinsurance broker under which we participate in the broker's revenue earned under our reinsurance treaties based on the volume of premium ceded. We estimate the amount of revenue we expect to receive under this agreement as premiums are recognized and ceded to the reinsurers.

Ceded Premiums Ratio

Ceded premiums ratio was as follows:

Year Ended December 31
20232022Change
Ceded premiums ratio, as reported34.6%34.1%0.5pts
Less the effect of:
Premiums ceded to SPCs (100%)23.6%24.6%(1.0pts)
Premiums ceded to unaffiliated captive insurers (100%)2.6%2.2%0.4pts
Change in return premium estimate under external reinsurance(0.4%)0.1%(0.5pts)
Estimated revenue share(0.7%)(0.7%)pts
Assumed premiums earned (not ceded to external reinsurers)(0.3%)(0.3%)pts
Change in reinstatement premium0.4%%0.4pts
EBUB estimate(0.1%)%(0.1pts)
Ceded premiums ratio (related to external reinsurance), less the effects of above9.5%8.2%1.3pts

The above table reflects traditional ceded premiums earned as a percent of traditional gross premiums earned. As discussed above, premiums ceded under our traditional reinsurance treaty are based on premiums earned during the treaty period. The increase in the ceded premiums ratio in 2023 as compared to 2022 primarily reflected the higher reinsurance rates.

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Net Premiums Earned

Net premiums earned consist of gross premiums earned less the portion of earned premiums that we cede to SPCs in our Segregated Portfolio Cell Reinsurance segment, external reinsurers (including changes related to the return premium and revenue share estimates) and the unaffiliated captive insurers. Because premiums are generally earned pro rata over the entire policy period, fluctuations in premiums earned tend to lag those of premiums written. Our workers’ compensation policies are twelve month term policies, and premiums are earned on a pro rata basis over the policy period. Net premiums earned also include premium adjustments related to the audit of our insureds' payrolls, changes in our estimates related to EBUB and premium adjustments related to retrospectively-rated policies. Payroll audits are conducted subsequent to the end of the policy period and any related premium adjustments are recorded as fully earned in the current period. We evaluate our estimates related to EBUB and retrospectively-rated premium adjustments on a quarterly basis with any adjustments being included in written and earned premium in the current period.

Net premiums earned were as follows:

Year Ended December 31
($ in thousands)20232022Change
Gross premiums earned$244,873$252,452$(7,579)(3.0%)
Less: Ceded premiums earned84,83986,081(1,242)(1.4%)
Net premiums earned$160,034$166,371$(6,337)(3.8%)

Net premiums earned decreased during the year ended December 31, 2023 as compared to 2022 primarily driven by the continuation of competitive market conditions resulting in lower renewal premium during the preceding twelve months, and reinstatement premium of $1.6 million recognized during the fourth quarter of 2023, partially offset by higher audit premium, including the increase in our carried EBUB estimate. See previous discussion on reinstatement premium in footnote 2 under the heading "Ceded Premiums Written."

Losses and Loss Adjustment Expenses

We estimate our current accident year loss and loss adjustment expenses by developing actual reported losses using historical loss development factors, adjusted to reflect current and expected trends based on various internal analyses and supplemental information. The following table summarizes calendar year net loss ratios by separating losses between the current accident year and all prior accident years. Calendar year and current accident year net loss ratios by component were as follows:

Year Ended December 31
20232022Change
Calendar year net loss ratio87.1%67.0%20.1pts
Less impact of prior accident years on the net loss ratio5.8%(4.8%)10.6pts
Current accident year net loss ratio81.3%71.8%9.5pts
Less estimated ratio increase (decrease) attributable to:
Change in ULAE6.4%5.9%0.5pts
Change in the AAD (1)3.6%3.0%0.6pts
Change in reinstatement premium1.0%%1.0pts
Current accident year net loss ratio, excluding the effect of items above70.3%62.9%7.4pts
(1) See previous discussion of the AAD under the heading "Ceded Premiums Written."

During the second half of 2023, we increased our current accident year net loss ratio and recognized unfavorable prior accident year reserve development, which reflected higher than expected loss trends observed in our average cost per claim. We continue to observe a reduction in reported claim frequency trends; however, the lower frequency is being more than offset by an increase in our average cost per claim in both the 2023 and 2022 accident years, which we attribute to increased medical costs driven by wage inflation and medical advancements. As shown in the previous table, the 2023 current accident year net loss ratio also reflects the impact of the aforementioned reinstatement premium and an increase in the ULAE ratio. The increase in the ULAE ratio primarily reflected lower net premiums earned.

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Calendar year incurred losses (excluding IBNR) in excess of our per occurrence reinsurance retention, before consideration of the AAD, increased $11.8 million in 2023 as compared to 2022, primarily reflecting unfavorable reserve development on one prior accident year reinsured claim. We recognized losses within the AAD totaling $5.8 million for the year ended December 31, 2023 as compared to $5.0 million in 2022. Accident year reported loss activity in excess of our per occurrence reinsurance retention totaled $2.2 million for 2023 as compared to $4.3 million in 2022.

We recognized net unfavorable prior year reserve development of $9.3 million for the year ended December 31, 2023 as compared to net favorable prior year development of $8.0 million for 2022. The net unfavorable prior year reserve development for the year ended December 31, 2023 reflected higher than expected average claim costs primarily in the 2022 accident year and higher than expected loss experience primarily attributable to a large claim from the 1997 accident year. The net favorable prior year development for the year ended December 31, 2022 reflected overall favorable trends in claim closing patterns primarily related to accident years 2020 and prior.

Underwriting, Policy Acquisition and Operating Expenses

Underwriting, policy acquisition and operating expenses include the amortization of commissions, premium taxes and underwriting salaries, which are capitalized and deferred over the related workers’ compensation policy period, net of ceding commissions earned. The capitalization of underwriting salaries can vary as they are subject to the success rate of our contract acquisition efforts. These expenses also include a management fee charged by our Corporate segment, which represents intercompany charges pursuant to a management agreement. The management fee is based on the extent to which services are provided to the subsidiary and the amount of premium written by the subsidiary.

Our Workers' Compensation Insurance segment underwriting, policy acquisition and operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20232022Change
DPAC amortization$29,486$29,585$(99)(0.3%)
Management fees1,8461,853(7)(0.4%)
Other underwriting and operating expenses36,99637,146(150)(0.4%)
Policyholder dividend expense1,01890211612.9%
SPC ceding commission offset(14,285)(14,749)464(3.1%)
Total$55,061$54,737$3240.6%

DPAC amortization was relatively unchanged for the year ended December 31, 2023 as compared to 2022, which reflected lower premium earned, partially offset by higher acquisition-related costs.

Other underwriting and operating expenses decreased slightly for the year ended December 31, 2023 as compared to 2022, primarily reflecting an increase in ULAE allocated to net losses and loss adjustment expenses and lower compensation-related costs, partially offset by higher IT and travel-related expenses. The decrease in compensation-related costs primarily reflected lower amounts accrued for performance-related incentive plans due to the decline of the related performance metrics, partially offset by higher salary costs. See additional discussion on ULAE in the previous section under the heading "Losses and Loss Adjustment Expenses."

As previously discussed, alternative market premiums written by our Workers' Compensation Insurance segment are 100% ceded, less a ceding commission, to either the SPCs in our Segregated Portfolio Cell Reinsurance segment or unaffiliated captive insurers. The ceding commission charged to the SPCs consists of an amount for fronting fees, cell rental fees, commissions, premium taxes, claims administration fees and risk management fees. The fronting fees, commissions, premium taxes and risk management fees are recorded as an offset to underwriting, policy acquisition and operating expenses. Cell rental fees are recorded as a component of other income and claims administration fees are recorded as ceded ULAE. The decrease in SPC ceding commissions earned for the year ended December 31, 2023 as compared to 2022, primarily reflected the decrease in alternative market ceded earned premium.

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Underwriting Expense Ratio (the Expense Ratio)

The underwriting expense ratio included the impact of the following:

Year Ended December 31
20232022Change
Underwriting expense ratio, as reported34.4%32.9%1.5pts
Less estimated ratio increase (decrease) attributable to:
Impact of ceding commissions received from SPCs1.8%3.9%(2.1pts)
Impact of audit premium(2.0%)(1.2%)(0.8pts)
Impact of reinstatement premium0.3%%0.3pts
Underwriting expense ratio, less listed effects34.3%30.2%4.1pts

Excluding the items noted in the table above, the expense ratio increased for the year ended December 31, 2023, primarily reflecting the impact of lower net premiums earned due to the continuation of competitive market conditions.

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Segment Results - Segregated Portfolio Cell Reinsurance

The Segregated Portfolio Cell Reinsurance segment includes the results (underwriting profit or loss, plus investment results, net of U.S. federal income taxes) of SPCs at Inova Re and Eastern Re, our Cayman Islands SPC operations, as discussed in Note 17 of the Notes to Consolidated Financial Statements. SPCs are segregated pools of assets and liabilities that provide an insurance facility for a defined set of risks. Assets of each SPC are solely for the benefit of that individual cell and each SPC is solely responsible for the liabilities of that individual cell. Assets of one SPC are statutorily protected from the creditors of the others. Each SPC is owned, fully or in part, by an individual company, agency, group or association and the results of the SPCs are attributable to the participants of that cell. We participate to a varying degree in the results of selected SPCs and, for the SPCs in which we participate, our participation interest ranges from a low of 15% to a high of 85%. SPC results attributable to external cell participants are reported as an SPC dividend (expense) income in our Segregated Portfolio Cell Reinsurance segment. In addition, our Segregated Portfolio Cell Reinsurance segment includes the investment results of the SPCs as the investments are solely for the benefit of the cell participants and investment results attributable to external cell participants are reflected in the SPC dividend (expense) income. As of December 31, 2023, there were twenty-seven (four inactive) SPCs. The SPCs assume workers' compensation insurance, healthcare professional liability insurance or a combination of the two from our Workers' Compensation Insurance and Specialty P&C segments. As of December 31, 2023, there were two SPCs that assumed both workers' compensation insurance and healthcare professional liability insurance and one SPC that assumed only healthcare professional liability insurance.

Segment results reflects our share of the underwriting and investment results of the SPCs in which we participate, and included the following:

Year Ended December 31
($ in thousands)20232022Change
Net premiums written$61,129$69,357$(8,228)(11.9%)
Net premiums earned$61,546$69,810$(8,264)(11.8%)
Net investment income2,2891,0291,260122.4%
Net investment gains (losses)3,680(3,067)6,747220.0%
Other income523150.0%
Net losses and loss adjustment expenses(36,363)(39,310)2,947(7.5%)
Underwriting, policy acquisition and operating expenses(20,457)(20,316)(141)0.7%
SPC U.S. federal income tax (expense) benefit (1)(1,629)(1,759)130(7.4%)
SPC net results9,0716,3892,68242.0%
SPC dividend (expense) income (2)(6,234)(6,673)439(6.6%)
Segment results (3)$2,837$(284)$3,1211,098.9%
Net loss ratio59.1%56.3%2.8 pts
Underwriting expense ratio33.2%29.1%4.1 pts
(1) Represents the provision for U.S. federal income taxes for SPCs at Inova Re, which have elected to be taxed as a U.S. corporation under Section 953(d) of the Internal Revenue Code. U.S. federal income taxes are included in the total SPC net results and are paid by the individual SPCs.
(2) Represents the net (profit) loss attributable to external cell participants.
(3) Represents our share of the net profit (loss) and OCI of the SPCs in which we participate.

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Premiums Written

Premiums in our Segregated Portfolio Cell Reinsurance segment are assumed from either our Workers' Compensation Insurance or Specialty P&C segments. Premium volume is driven by five primary factors: (1) the amount of new business written, (2) retention of the existing book of business, (3) premium rates charged on the renewal book of business and, for workers' compensation business, (4) changes in payroll exposure and (5) audit premium.

Gross, ceded and net premiums written were as follows:

Year Ended December 31
($ in thousands)20232022Change
Gross premiums written$70,259$78,937$(8,678)(11.0%)
Less: Ceded premiums written9,1309,580(450)(4.7%)
Net premiums written$61,129$69,357$(8,228)(11.9%)

Gross Premiums Written

Gross premiums written reflected reinsurance premiums assumed by component as follows:

Year Ended December 31
($ in thousands)20232022Change
Workers' compensation$64,619$68,035$(3,416)(5.0%)
Healthcare professional liability5,64010,902(5,262)(48.3%)
Gross Premiums Written$70,259$78,937$(8,678)(11.0%)

Gross premiums written for the years ended December 31, 2023 and 2022 were primarily comprised of workers' compensation coverages assumed from our Workers' Compensation Insurance segment. Workers' compensation gross premiums written decreased during the year ended December 31, 2023 as compared to 2022 driven by lower renewal and audit premium. Renewal premium for 2023 reflected retention of 89% and rate decreases of 5%, partially offset by an increase in payroll exposure. The decrease in healthcare professional liability gross premiums written in 2023 as compared to 2022 primarily reflected the prior year impact of tail coverage related to one program, in which we do not participate in the underwriting results. See further discussion in our Segment Results - Specialty Property & Casualty section under the heading "Premiums Written." We retained 100% of the twenty-two workers' compensation and three healthcare professional liability alternative market programs up for renewal for the year ended December 31, 2023.

New business, audit premium, retention and renewal price changes for the assumed workers' compensation premium is shown in the table below:

Year Ended December 31
($ in millions)20232022
New business$4.2$3.6
Audit premium$3.6$5.4
Retention rate (1)89%87%
Change in renewal pricing (2)(5%)(4%)
(1) We calculate our workers' compensation retention rate as annualized expiring renewed premium divided by all annualized expiring premium subject to renewal. Our retention rate can be impacted by various factors, including price or other competitive issues, insureds being acquired, or a decision not to renew based on our underwriting evaluation.
(2) The pricing of our business includes an assessment of the underlying policy exposure and market conditions. We continue to base our pricing on expected losses, as indicated by our historical loss data.

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Ceded Premiums Written

Ceded premiums written were as follows:

Year Ended December 31
($ in thousands)20232022Change
Ceded premiums written$9,130$9,580$(450)(4.7%)

For the workers' compensation business, each SPC has in place its own external reinsurance coverage. The healthcare professional liability business is assumed net of reinsurance from our Specialty P&C segment; therefore, there are no ceded premiums related to the healthcare professional liability business reflected in the table above. The risk retention for each loss occurrence for the workers' compensation business ranges from $0.3 million to $0.4 million based on the program, with limits up to $119.7 million. In addition, each program has aggregate reinsurance coverage between $1.1 million and $2.1 million on a program year basis. Premiums ceded under our SPC reinsurance treaty are based on premiums written during the treaty period. The change in ceded premiums written in 2023 as compared to 2022 primarily reflected the decrease in workers' compensation gross premiums written and the impact of rate changes under the external reinsurance treaty. External reinsurance rates vary based on the alternative market program.

Ceded Premiums Ratio

Ceded premiums ratio was as follows:

Year Ended December 31
20232022Change
Ceded premiums ratio14.1%14.1%pts

The above table reflects ceded premiums as a percent of gross premiums written for the workers' compensation business only; healthcare professional liability business is assumed net of reinsurance, as discussed above. The ceded premiums ratio reflects the weighted average reinsurance rates of all SPC programs.

Net Premiums Earned

Net premiums earned consist of gross premiums earned less the portion of earned premiums that the SPCs cede to external reinsurers. Because premiums are generally earned pro rata over the entire policy period, fluctuations in premiums earned tend to lag those of premiums written. Policies ceded to the SPCs are twelve month term policies and premiums are earned on a pro rata basis over the policy period. Net premiums earned also include premium adjustments related to the audit of workers' compensation insureds' payrolls. Payroll audits are conducted subsequent to the end of the policy period and any related adjustments are recorded as fully earned in the current period.

Gross, ceded and net premiums earned were as follows:

Year Ended December 31
($ in thousands)20232022Change
Gross premiums earned$70,706$79,347$(8,641)(10.9%)
Less: Ceded premiums earned9,1609,537(377)(4.0%)
Net premiums earned$61,546$69,810$(8,264)(11.8%)

The decrease in net premiums earned during the year ended December 31, 2023 as compared to 2022, primarily reflected the prior year impact of healthcare professional liability tail coverage, as previously discussed. Net premiums earned related to the workers' compensation business decreased in 2023 driven by the pro rata effect of a reduction in net premiums written during the preceding twelve months, including a reduction in audit premium.

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Losses and Loss Adjustment Expenses

The following table summarizes the calendar year net loss ratios by separating losses between the current accident year and all prior accident years. The current accident year net loss ratio reflects the aggregate loss ratio for all programs. Loss reserves and associated reinsurance are estimated for each program on a quarterly basis. Each SPC has in place its own reinsurance agreement, and the attachment point of aggregate reinsurance coverage varies by program. Due to the size of some of the programs, quarterly loss results, including changes in estimated aggregate reinsurance, can create volatility in the current accident year net loss ratio from period to period.

Calendar year and current accident year net loss ratios for the years ended December 31, 2023 and 2022 were as follows:

Year Ended December 31
20232022Change
Calendar year net loss ratio59.1%56.3%2.8pts
Less impact of prior accident years on the net loss ratio(6.4%)(9.0%)2.6pts
Current accident year net loss ratio65.5%65.3%0.2pts
Less estimated ratio increase (decrease) attributable to:
Change in estimated aggregate reinsurance (1)0.4%0.9%(0.5pts)
Current accident year net loss ratio, excluding the effect of the change in estimated aggregate reinsurance65.1%64.4%0.7pts
(1) See additional information regarding the SPC's aggregate reinsurance agreements in our Liquidity and Capital Resources and Financial Condition section under the heading "Operating Activities and Related Cash Flows."

The current accident year net loss ratio, excluding the effect of changes in estimated aggregate reinsurance, increased in 2023 as compared to 2022, reflecting a higher healthcare professional liability current accident year net loss ratio, partially offset by a lower workers' compensation current accident year net loss ratio. The decrease in the workers' compensation current accident year net loss ratio for 2023 primarily reflected a reduction in reported claim frequency. The increase in the healthcare professional liability current accident year loss ratio for 2023 primarily reflected an increase in expected claim frequency related to one program in which we do not participate in the underwriting results.

Calendar year incurred losses (excluding IBNR) ceded to our external reinsurers decreased $6.1 million for the year ended December 31, 2023 as compared to 2022. Current accident year ceded incurred losses (excluding IBNR) decreased $6.6 million for the year ended December 31, 2023 as compared to 2022.

We recognized net favorable prior year reserve development of $4.0 million and $6.3 million for the years ended December 31, 2023 and 2022, respectively. The development in 2023 includes net favorable development in the workers' compensation business of $5.3 million and net unfavorable development of $1.3 million in the healthcare professional liability business. The net favorable development related to the workers' compensation business in 2023 reflected overall favorable trends in claim closing patterns primarily in accident years 2016 through 2021. The net unfavorable development in the healthcare professional liability business in 2023 primarily reflected higher than expected claim frequency in one program in which we do not participate in the underwriting results. The development in 2022 includes net favorable development in the workers' compensation business of $7.0 million, partially offset by net unfavorable development of $0.7 million in the healthcare professional liability business. The net favorable development in the workers' compensation business in 2022 reflected overall favorable trends in claim closing patterns primarily in accident years 2016 through 2021. The net unfavorable development in the healthcare professional liability business primarily in 2022 reflected higher than expected claim frequency in one program in which we do not participate.

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Underwriting, Policy Acquisition and Operating Expenses

Our Segregated Portfolio Cell Reinsurance segment underwriting, policy acquisition and operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20232022Change
DPAC amortization$18,371$20,068$(1,697)(8.5%)
Policyholder dividend expense339167172103.0%
Other underwriting and operating expenses1,747811,6662,056.8%
Total$20,457$20,316$1410.7%

DPAC amortization primarily represents ceding commissions, which vary by program and are paid to our Workers' Compensation Insurance and Specialty P&C segments for premiums assumed. Ceding commissions include an amount for fronting fees, commissions, premium taxes and risk management fees, which are reported as an offset to underwriting, policy acquisition and operating expenses within our Workers' Compensation Insurance and Specialty P&C segments. In addition, ceding commissions paid to our Workers' Compensation Insurance segment include cell rental fees which are recorded as other income and claims administration fees which are recorded as ceded ULAE within our Workers' Compensation Insurance segment. The decrease in DPAC amortization in 2023 as compared to 2022 primarily reflected a decrease in earned premium, as discussed above under the heading "Net Premiums Earned."

Policyholder dividend expense increased in 2023 as compared to 2022 driven by changes in estimated dividends for one SPC program, in which we do not participate in the underwriting results.

Other underwriting and operating expenses primarily include bank fees, professional fees and changes in the allowance for expected credit losses. Other underwriting and operating expenses increased in 2023 due to the collection in 2022 of a large customer account balance that was previously written off in 2021. Excluding the impact of a reduction in the allowance for credit losses, other underwriting and operating expenses 2023 were relatively unchanged as compared to the same period of 2022.

Underwriting Expense Ratio (the Expense Ratio)

The underwriting expense ratio included the impact of the following:

Year Ended December 31
20232022Change
Underwriting expense ratio, as reported33.2%29.1%4.1pts
Less: impact of audit premium on expense ratio(2.1%)(2.3%)0.2pts
Underwriting expense ratio, excluding the effect of audit premium35.3%31.4%3.9pts

Excluding the effect of audit premium, the underwriting expense ratio increased for the year ended December 31, 2023 as compared to 2022 primarily driven by the prior year impact of a reduction in the allowance for credit losses for one program in which we do not participate in the underwriting results, as previously discussed.

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Segment Results - Corporate

Our Corporate segment includes our investment operations excluding those reported in our Segregated Portfolio Cell Reinsurance segment as discussed in Note 16 of the Notes to Consolidated Financial Statements. In addition, this segment includes corporate expenses, interest expense, U.S. and U.K. income taxes and non-premium revenues generated outside of our insurance entities. As previously discussed under the heading "ProAssurance Overview," we reorganized our segment reporting in the third quarter of 2023. As a result, the investment results of assets solely allocated to our Lloyd's Syndicate operations and U.K. income taxes which were previously reported in our Lloyd’s Syndicates segment are now reported in our Corporate segment. All prior period segment information has been recast to conform to the current period presentation. See further information regarding our segments in Note 16 of the Notes to Consolidated Financial Statements.

Segment results for the year ended December 31, 2023 and 2022 exclude the change in fair value of contingent consideration and, for the year ended December 31, 2022, transaction-related costs including the associated income tax benefit related to the NORCAL acquisition as we do not consider these items in assessing the financial performance of the segment. We did not incur any transaction-related costs in 2023. For additional information on the NORCAL acquisition see Note 2 of the Notes to Consolidated Financial Statements in our December 31, 2022 report on Form 10-K. Segment results for our Corporate segment were net earnings of $89.8 million and $17.3 million for the years ended December 31, 2023 and 2022, respectively, and included the following:

Year Ended December 31
($ in thousands)20232022Change
Net investment income$126,130$94,943$31,18732.8%
Equity in earnings (loss) of unconsolidated subsidiaries$6,791$4,888$1,90338.9%
Net investment gains (losses)$5,148$(39,090)$44,238113.2%
Other income$8,307$6,198$2,10934.0%
Operating expense$34,007$34,733$(726)(2.1%)
Interest expense$23,150$20,372$2,77813.6%
Income tax expense (benefit)$(545)$(5,423)$4,87890.0%

Net Investment Income

Net investment income is primarily derived from the income earned by our fixed maturity securities and also includes dividend income from equity securities, income from our short-term and cash equivalent investments, earnings from other investments and changes in the cash surrender value of BOLI contracts, net of investment fees and expenses.

Net investment income (loss) by investment category was as follows:

Year Ended December 31
($ in thousands)20232022Change
Fixed maturities$112,270$92,626$19,64421.2%
Equities4,6103,70690424.4%
Short-term investments, including Other14,2625,4148,848163.4%
BOLI2,4891,1411,348118.1%
Investment fees and expenses(7,501)(7,944)443(5.6%)
Net investment income$126,130$94,943$31,18732.8%

Fixed Maturities

Income from our fixed maturities increased in 2023 as compared to 2022 driven by higher average book yields as we continue to reinvest at higher rates as our portfolio matures. However, average investment balances were approximately 1.7% lower for 2023 as compared to 2022 as we have reduced the rate of reinvestment in order to allow for additional cash availability, primarily related to operating costs and the repurchase of common shares pursuant to the existing share repurchase authorization. See additional information on our operating cash flows and repurchase of common shares in the Liquidity section under the heading "Cash Flows" and "Treasury Shares," respectively.

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Average yields for our fixed maturity portfolio were as follows:

Year Ended December 31
20232022
Average income yield3.1%2.5%
Average tax equivalent income yield3.1%2.5%

Short-term Investments and Other Investments

Short-term investments, which have a maturity at purchase of one year or less are carried at fair value, which approximates their cost basis, and are primarily composed of investments in U.S. treasury obligations, commercial paper, money market funds and a certificate of deposit. Income from our short-term and other investments increased during 2023 as compared to 2022 primarily due to higher yields given the increase in interest rates and, to a lesser extent, higher average investment balances.

BOLI

We hold BOLI policies that are carried at the current cash surrender value of the policies. All insured individuals were members of management at the time the policies were acquired. Income from our BOLI policies increased in 2023 as compared to 2022 primarily attributable to an increase in the cash surrender value.

Equity in Earnings (Loss) of Unconsolidated Subsidiaries

Equity in earnings (loss) of unconsolidated subsidiaries was comprised as follows:

Year Ended December 31
($ in thousands)20232022Change
All other investments, primarily investment fund LPs/LLCs$9,196$11,954$(2,758)(23.1%)
Tax credit partnerships(2,405)(7,066)4,661(66.0%)
Equity in earnings (loss) of unconsolidated subsidiaries$6,791$4,888$1,90338.9%

We hold interests in certain LPs/LLCs that generate earnings from trading portfolios, secured debt, debt securities, multi-strategy funds and private equity investments. The performance of the LPs/LLCs is affected by the volatility of equity and credit markets. For our investments in LPs/LLCs, we record our allocable portion of the partnership operating income or loss as the results of the LPs/LLCs become available, typically following the end of a reporting period. Our investment results from our portfolio of investments in LPs/LLCs for 2023 as compared to 2022 decreased primarily due to the performance of several LP/LLCs which reflected lower market valuations during the fourth quarter of 2022 and first quarter of 2023.

Our tax credit partnership investments are designed to generate returns in the form of tax credits and tax-deductible project operating losses and are comprised of qualified affordable housing project tax credit partnerships and a historic tax credit partnership. The results from our tax credit partnership investments for the year ended December 31, 2023 reflected lower partnership operating losses as compared to 2022. See additional information on our tax credit partnership investments in Note 3 of the Notes to Consolidated Financial Statements.

The tax benefits received from our tax credit partnerships, which are not reflected in our investment results, reduced our tax expense in 2023 and 2022 as follows:

Year Ended December 31
(In millions)20232022
Tax credits recognized during the period$0.6$4.8
Tax benefit of tax credit partnership operating losses$0.5$1.5

The tax credits generated from our tax credit partnership investments of $0.6 million for 2023 were deferred to be utilized in future periods due to our expected consolidated loss calculated on a tax basis. For the year ended December 31, 2022, the tax credits generated from our tax credit partnership investments of $4.8 million were deferred to be utilized in future periods. For further discussion on our tax credits, see Note 3 and Note 5 of the Notes to Consolidated Financial Statements.

Tax credits provided by the underlying projects of our historic tax credit partnership are typically available in the tax year in which the project is put into active service, whereas the tax credits provided by qualified affordable housing project tax credit partnerships are provided over approximately a ten year period.

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Net Investment Gains (Losses)

The following table provides detailed information regarding our net investment gains (losses).

Year Ended December 31
(In thousands)20232022
Total impairment losses
Corporate debt$(2,984)$(1,331)
Asset-backed securities(127)(441)
Portion of impairment losses recognized in other comprehensive income before taxes:
Asset-backed securities14
Net impairment losses recognized in earnings(3,111)(1,758)
Gross realized gains, available-for-sale fixed maturities8751,657
Gross realized (losses), available-for-sale fixed maturities(1,800)(3,245)
Net realized gains (losses), trading fixed securities(88)(155)
Net realized gains (losses), equity investments(7)(5,928)
Net realized gains (losses), other investments(2,417)(222)
Change in unrealized holding gains (losses), trading fixed securities68(613)
Change in unrealized holding gains (losses), equity investments2,495(18,483)
Change in unrealized holding gains (losses), convertible securities, carried at fair value as a part of other investments5,774(10,557)
Other3,359214
Net investment gains (losses)$5,148$(39,090)

For the year ended December 31, 2023, we recognized $3.1 million of credit-related impairment losses in earnings related to a mortgage-backed security and two corporate bonds in the financial sector. We did not recognize any non-credit impairment losses in OCI in 2023. For the year ended December 31, 2022, we recognized credit-related impairment losses in earnings of $1.8 million and a nominal amount of non-credit impairment losses in OCI. The credit-related and non-credit impairment losses in OCI during the year ended December 31, 2022 related to a corporate bond in the consumer sector as well as certain mortgage-backed and other asset backed securities.

We recognized $5.1 million of net investment gains for the year ended December 31, 2023 driven by unrealized holding gains resulting from changes in the fair value of our convertible securities, death benefit proceeds from BOLI contracts and, to a lesser extent, unrealized holding gains resulting from changes in the fair value of our equity investments. We recognized $39.1 million of net investment losses for the year ended December 31, 2022 driven by unrealized holding losses resulting from changes in the fair value of our equity investments and convertible securities and, to a lesser extent, realized losses from the sale of equity investments.

Other Income

Corporate other income for the year ended December 31, 2023 as compared to 2022 was comprised of the following:

Year Ended December 31
($ in thousands)20232022Change
Foreign currency exchange rate gains/(losses)(1)$(2,993)$2,022$(5,015)(248.0%)
Other11,3004,1767,124170.6%
Total other income$8,307$6,198$2,10934.0%
(1) See further information on foreign currency exchange rate gains (losses) in the Executive Summary of Operations section under the heading "Revenues."

Excluding the foreign currency exchange rate gains (losses), other income increased for the year ended December 31, 2023 as compared to 2022 driven by proceeds of $6.9 million received in 2023 associated with the sale of our remaining ownership interest in the underwriting and operations entity associated with Syndicate 1729 to unrelated third parties.

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Operating Expenses

Corporate segment operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20232022Change
Operating expenses$39,747$41,350$(1,603)(3.9%)
Management fee offset(5,740)(6,617)877(13.3%)
Total$34,007$34,733$(726)(2.1%)

Operating expenses decreased during the year ended December 31, 2023 as compared to 2022 driven by a decrease in compensation-related costs and, to a lesser extent, a decrease in professional fees. The decrease in compensation-related costs during 2023 primarily reflected lower amounts accrued for performance-related incentive plans due to the decline of the related performance metrics. The decrease in professional fees during 2023 was primarily attributable to a decrease in consulting fees and, to a lesser extent, employee placement fees as a result of filling more open positions across the organization in 2022 as compared to 2023.

Core domestic operating subsidiaries within our Specialty P&C segment and our Workers' Compensation Insurance segment are charged a management fee by the Corporate segment for services provided to these subsidiaries. The management fee is based on the extent to which services are provided to the subsidiary and the amount of premium written by the subsidiary. Under the arrangement, the expenses associated with such services are reported as expenses of the Corporate segment, and the management fees charged are reported as an offset to Corporate operating expenses. While the terms of the arrangement were generally consistent between 2023 and 2022, fluctuations in the amount of premium written by each subsidiary can result in corresponding variations in the management fee charged to each subsidiary during a particular period.

Interest Expense

Consolidated interest expense for the years ended December 31, 2023 and 2022 was comprised as follows:

Year Ended December 31
($ in thousands)20232022Change
Senior Notes due 2023$11,742$13,429$(1,687)(12.6%)
Contribution Certificates (including accretion)(1)7,5677,3322353.2%
Revolving Credit Agreement (including fees and amortization)2,4941,0161,478145.5%
Term Loan (including fees and amortization)1,3921,392nm
(Gain)/loss on cash flow hedges reclassified from AOCI(2)(45)(45)nm
(Gain)/loss on interest rate cap(1,405)1,405nm
Interest expense$23,150$20,372$2,77813.6%
(1) Includes accretion of approximately $1.9 million and $1.8 million for the years ended December 31, 2023 and 2022, respectively, which is recorded as an increase to interest expense as a result of the difference between the recorded acquisition date fair value and the principal balance of the Contribution Certificates associated with our acquisition of NORCAL.
(2) We entered into two forward-starting interest rate swap agreements ("Interest Rate Swaps") on May 2, 2023, each of which are designated and qualify as a cash flow hedge. See Note 11 of the Notes to Consolidated Financial Statements for additional information on the Interest Rate Swaps.

Consolidated interest expense increased during 2023 as compared to 2022 driven by our short-term exposure to variability in the base rates on the borrowings under both the amended Revolving Credit Agreement and Term Loan from November 15, 2023 until the Interest Rate Swaps were effective on December 29, 2023. Interest expense on our Revolving Credit Agreement for the year ended December 31, 2022 primarily reflected unused commitment fees as there were no outstanding borrowings during the period. In addition, the increase in consolidated interest expense during 2023 reflected the prior year impact of the change in the fair value of our interest rate cap which was terminated in the second quarter of 2022. See further discussion on our outstanding debt in Note 10 of the Notes to Consolidated Financial Statements.

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Taxes

Tax expense allocated to our Corporate segment includes U.S. and U.K. tax expense including U.S. tax expense incurred from our corporate membership in Lloyd's of London, if any. The SPCs at Inova Re, one of our Cayman Islands reinsurance subsidiaries, have each made a 953(d) election under the U.S. Internal Revenue Code and are subject to U.S. federal income tax; therefore, tax expense allocated to our Corporate segment also includes tax expense incurred from any SPC at Inova Re in which we have a participation interest of 80% or greater as those SPCs are required to be included in our consolidated tax return. Consolidated tax expense (benefit) reflects the tax expense (benefit) of both segments and the tax impact of items excluded from segment reporting, as shown in the table below:

Year Ended December 31
(In thousands)20232022
Corporate segment income tax expense (benefit)$(545)$(5,423)
Income tax expense (benefit) - transaction-related costs*(391)
Consolidated income tax expense (benefit)$(545)$(5,814)
*Represents the income tax benefit associated with the transaction-related costs related to our acquisition of NORCAL that are not included in a segment as we do not consider these costs in assessing the financial performance of any of our operating or reportable segments. See Note 16 of the Notes to Consolidated Financial Statements for a reconciliation of our segment results to our consolidated results.

Listed below are the primary factors affecting our consolidated effective tax rate for the years ended December 31, 2023 and 2022. These factors include the following:

Year Ended December 31
20232022
($ in thousands)Income tax (benefit) expenseRate ImpactIncome tax (benefit) expenseRate Impact
Computed "expected" tax expense (benefit) at statutory rate$(8,221)21.0%$(1,305)21.0%
Tax-exempt income(1)(1,192)3.0%(1,072)17.2%
Tax credits(631)1.6%(4,805)77.3%
Non-U.S. operating results(625)1.7%(411)6.6%
Tax deficiency (excess tax benefit) on share-based compensation191(0.5%)309(5.0%)
Non-taxable contingent consideration(2)(1,785)4.6%(1,890)30.4%
Goodwill impairment(3)9,263(23.7%)%
Provision-to-return and other differences327(0.8%)1,112(17.9%)
Change in uncertain tax positions1,546(3.9%)780(12.5%)
Change in limitation of future deductibility of certain executive compensation932(2.4%)708(11.4%)
GILTI and subpart F income396(1.0%)556(8.9%)
State income taxes65(0.2%)105(1.7%)
Non-taxable gain from life insurance proceeds(682)1.7%(142)2.3%
Other(129)0.3%241(3.9%)
Total income tax expense (benefit)$(545)1.4%$(5,814)93.5%

(1) Includes tax-exempt interest, dividends received deduction and change in cash surrender value of BOLI.

(2) Represents the tax impact of decreases in the contingent consideration liability issued in connection with the NORCAL acquisition of $8.5 million and $9.0 million for the years ended December 31, 2023 and 2022, respectively, all of which are non-taxable. See further discussion on the contingent consideration in Note 2 and Note 8 of the Notes to Consolidated Financial Statements.

(3) Represents the tax impact of the impairment of non-deductible goodwill in relation to the Workers' Compensation Insurance reporting unit during the third quarter of 2023 (see further discussion on the impairment charge under the heading "Goodwill / Intangibles" in the Critical Accounting Estimates section and in Note 6 of the Notes to Consolidated Financial Statements).

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Our consolidated effective tax rate for 2023, as shown in the table above, differed from the statutory federal income tax rate of 21% primarily due to a $44.1 million goodwill impairment recognized in relation to the Workers' Compensation Insurance reporting unit during the third quarter of 2023, all of which is non-deductible. See further discussion on this goodwill impairment in Note 6 of the Notes to Consolidated Financial Statements. Our consolidated effective tax rate for 2022 differed from the statutory federal income tax rate of 21% primarily due to the benefit recognized from the tax credits transferred to us from our tax credit partnership investments. In addition, our effective tax rates for 2023 and 2022 were impacted by the $8.5 million and $9.0 million, respectively, decrease in the contingent consideration liability related to the NORCAL acquisition, all of which was non-taxable. See further discussion on the contingent consideration in Note 2 and Note 8 of the Notes to Consolidated Financial Statements. There were no other individually significant items impacting our effective tax rates for 2023 and 2022.

Results of Operations - Year Ended December 31, 2022 Compared to Year Ended December 31, 2021

Other than as described below, there have been no other significant retrospective revisions in the presentation of the changes in the financial condition, results of operations and cash flows for the year ended December 31, 2022 as compared to the year ended December 31, 2021 as disclosed in Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" section of ProAssurance's December 31, 2022 report on Form 10-K.

Executive Summary of Operations

Revenues

The following table shows our consolidated and segment net premiums earned:

Year Ended December 31
($ in thousands)20222021Change
Net premiums earned
Specialty P&C$793,400$743,380$50,0206.7%
Workers' Compensation Insurance166,371164,6001,7711.1%
Segregated Portfolio Cell Reinsurance69,81063,6886,1229.6%
Consolidated total$1,029,581$971,668$57,9136.0%

For the year ended December 31, 2022, consolidated net premiums earned included earned premium from our acquisition of NORCAL of $289.0 million as compared to $214.6 million in 2021. Excluding NORCAL premiums, our consolidated net premiums earned decreased $16.5 million in 2022 as compared to 2021.

•Net premiums earned in our Specialty P&C segment, excluding NORCAL premiums, decreased in 2023 as compared to 2021 due to our decreased participation in the results of Syndicate 1729 and Syndicate 6131 for the 2021 underwriting year and, to a lesser extent, our ceased participation in Syndicate 6131 for the 2022 underwriting year.

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Expenses

The following table shows our consolidated and segment net loss ratios and net prior accident year reserve development.

Year Ended December 31
($ in millions)20222021Change
Current accident year net loss ratio
Consolidated ratio79.0%82.1%(3.1pts)
Specialty P&C81.7%85.2%(3.5pts)
Workers' Compensation Insurance71.8%74.0%(2.2pts)
Segregated Portfolio Cell Reinsurance65.3%67.1%(1.8pts)
Calendar year net loss ratio
Consolidated ratio75.4%77.4%(2.0pts)
Specialty P&C78.9%81.4%(2.5pts)
Workers' Compensation Insurance67.0%69.7%(2.7pts)
Segregated Portfolio Cell Reinsurance56.3%51.1%5.2pts
Favorable (unfavorable) reserve development, prior accident years
Consolidated$36.8$45.5$(8.7)
Specialty P&C$22.5$28.2$(5.7)
Workers' Compensation Insurance$8.0$7.1$0.9
Segregated Portfolio Cell Reinsurance$6.3$10.2$(3.9)

In both 2022 and 2021, our consolidated calendar year net loss ratio was lower than our consolidated current accident year net loss ratio due to the recognition of net favorable prior year reserve development, as shown in the previous table. The following table shows the components of our consolidated net prior accident year reserve development:

Year Ended December 31
($ in thousands)20222021Change
Net favorable reserve development$25,934$37,576$(11,642)(31.0%)
NORCAL Acquisition - Purchase Accounting Amortization*10,8197,9072,91236.8%
Total net favorable reserve development$36,753$45,483$(8,730)(19.2%)
*See Note 2 of the Notes to Consolidated Financial Statements in our December 31, 2022 report on Form 10-K for additional information on the purchase accounting adjustments.

•Development recognized in our Specialty P&C segment during 2022 principally related to accident years 2017 and 2020 through 2021. Net favorable prior accident year reserve development recognized in our Specialty P&C segment included favorable development related to NORCAL's 2021 accident year and, to a lesser extent, our Medical Technology Liability line of business. The unfavorable development recognized in our HCPL line of business was driven by higher than anticipated loss severity trends in select jurisdictions, which emerged primarily in the fourth quarter of 2022. Further, we recognized $7.3 million of unfavorable prior year development in our Lloyd's Syndicates business during the year ended December 31, 2022 driven by higher than expected losses and development on certain large claims, primarily catastrophe related losses.

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Our consolidated and segment underwriting expense ratios were as follows:

Year Ended December 31
20222021Change
Underwriting Expense Ratio
Consolidated (1)29.9%27.6%2.3pts
Specialty P&C25.2%19.6%5.6pts
Workers' Compensation Insurance32.9%31.8%1.1pts
Segregated Portfolio Cell Reinsurance29.1%34.0%(4.9pts)
Corporate (2)3.4%2.7%0.7pts
(1) Consolidated underwriting expenses include transaction-related costs for 2022 and 2021 associated with our acquisition of NORCAL that are not included in a segment as we do not consider these costs in assessing the financial performance of any of our operating or reportable segments. See Note 16 of the Notes to Consolidated Financial Statements in our December 31, 2022 report on Form 10-K for a reconciliation of our segment results to our consolidated results.
(2) There are no net premiums earned associated with the Corporate segment. Ratios shown are the contribution of the Corporate segment to the consolidated ratio (Corporate operating expenses divided by consolidated net premiums earned).

Segment Results - Specialty Property & Casualty

As previously discussed, we reorganized our segment reporting in the third quarter of 2023. As a result, we now report the underwriting results from our participation in Lloyd’s Syndicates in the Specialty P&C segment. All prior period segment information has been recast to conform to the current period presentation. See further information in Note 16 of the Notes to Consolidated Financial Statements.

Our Specialty P&C segment focuses on professional liability insurance and medical technology liability insurance. On May 5, 2021, we completed our acquisition of NORCAL, an underwriter of healthcare professional liability insurance (Note 2 of the Notes to Consolidated Financial Statements provides additional information regarding this acquisition). Segment results reflected pre-tax underwriting profit or loss from these insurance lines and included the amortization of certain purchase accounting adjustments. Segment results for the years ended December 31, 2022 and 2021 exclude transaction-related costs and, for 2021, a $74.4 million gain on bargain purchase associated with our acquisition of NORCAL as we do not consider these items in assessing the financial performance of the segment. Segment results included the following:

Year Ended December 31
($ in thousands)20222021Change
Net premiums written$784,020$657,814$126,20619.2%
Net premiums earned$793,400$743,380$50,0206.7%
Other income5,1224,28284019.6%
Net losses and loss adjustment expenses(626,045)(604,976)(21,069)3.5%
Underwriting, policy acquisition and operating expenses(199,809)(145,666)(54,143)37.2%
Segment results$(27,332)$(2,980)$(24,352)(817.2%)
Net loss ratio78.9%81.4%(2.5pts)
Underwriting expense ratio25.2%19.6%5.6pts

Premiums Written

Gross, ceded and net premiums written were as follows:

Year Ended December 31
($ in thousands)20222021Change
Gross premiums written$856,861$719,478$137,38319.1%
Less: Ceded premiums written72,84161,66411,17718.1%
Net premiums written$784,020$657,814$126,20619.2%

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Gross Premiums Written

Gross premiums written by component were as follows:

Year Ended December 31
($ in thousands)20222021Change
Professional Liability
HCPL
Standard Physician$204,086$209,938$(5,852)(2.8%)
NORCAL Standard Physician240,391111,673128,718115.3%
Total Standard Physician444,477321,611122,86638.2%
Specialty
Custom Physician51,11646,2104,90610.6%
NORCAL Custom Physician30,14616,39413,75283.9%
Hospitals and Facilities56,12151,3104,8119.4%
NORCAL Hospitals and Facilities12,8609,9552,90529.2%
Senior Care6,3546,708(354)(5.3%)
Reinsurance assumed43,44937,7555,69415.1%
Total Specialty200,046168,33231,71418.8%
Total HCPL644,523489,943154,58031.6%
Small Business Unit102,524103,083(559)(0.5%)
Tail Coverages29,00930,637(1,628)(5.3%)
NORCAL Tail Coverages18,64616,0922,55415.9%
Total Professional Liability794,702639,755154,94724.2%
Medical Technology Liability41,06540,997680.2%
Lloyd's Syndicates(1)20,23337,969(17,736)(46.7%)
Other86175710413.7%
Total Gross Premiums Written$856,861$719,478$137,38319.1%

(1) Our Lloyd's Syndicates business includes the results from our participation in Syndicate 1729 and Syndicate 6131 at Lloyd's of London. For each of the 2022 and 2021 underwriting years our participation in the results of Syndicate 1729 is approximately 5%. Effective January 1, 2022, Syndicate 6131 ceased underwriting on a quota share basis with Syndicate 1729. Due to the quarter lag, our ceased participation in Syndicate 6131 was not reflected in our results until the second quarter of 2022. Our Lloyd’s Syndicates premium decreased during 2022 as compared to 2021 driven by the impact of our decreased participation in the results of Syndicates 1729 and 6131 for the 2021 underwriting year and our ceased participation in Syndicate 6131 for the 2022 underwriting year. The decrease in net premiums written in 2022 was partially offset by volume increases on renewal business and renewal pricing increases, primarily on property and specialty insurance coverages, as well as new business written, primarily on property insurance and casualty coverages.

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Ceded Premiums Written

Ceded premiums written were as follows:

Year Ended December 31
($ in thousands)20222021Change
Excess of loss reinsurance arrangements$38,005$30,622$7,38324.1%
Other shared risk arrangements19,04916,1122,93718.2%
Premium ceded to SPCs10,9027,2113,69151.2%
NORCAL premiums ceded since acquisition2,253(2,253)nm
Other ceded premiums written (1)7,7139,402(1,689)(18.0%)
Adjustment to premiums owed under reinsurance agreements, prior accident years, net(2,828)(3,936)1,108(28.2%)
Total ceded premiums written$72,841$61,664$11,17718.1%

(1)The decrease in other ceded premiums written in 2022 as compared to 2021 was primarily driven by our decreased participation in the results of Syndicate 1729 and Syndicate 6131 for the 2021 underwriting year and, to a lesser extent, our ceased participation in Syndicate 6131 for the 2022 underwriting year. The decrease in other ceded premiums written in 2022 was partially offset by the incorporation of NORCAL's cyber liability coverages into our existing HCPL cyber liability arrangement with the January 1, 2022 renewal.

Ceded Premiums Ratio

As shown in the table below, our ceded premiums ratio was affected in both 2022 and 2021 by revisions to our estimate of premiums owed to reinsurers related to coverages provided in prior accident years. The ceded premiums ratio was as follows:

Year Ended December 31
20222021Change
Ceded premiums ratio8.5%8.6%(0.1pts)
Less the effect of adjustments in premiums owed under reinsurance agreements, prior accident years (as previously discussed)(0.3%)(0.5%)0.2pts
Ratio, current accident year8.8%9.1%(0.3pts)

The above table reflects ceded premiums written, excluding the effect of prior year ceded premium adjustments, as previously discussed, as a percent of gross premiums written. Our ceded premiums ratio remained relatively unchanged for 2022 as compared to 2021. See additional discussion above under the heading "Ceded Premiums Written."

Net Premiums Earned

Net premiums earned were as follows:

Year Ended December 31
($ in thousands)20222021Change
Gross premiums earned$861,986$822,001$39,9854.9%
Less: Ceded premiums earned68,58678,621(10,035)(12.8%)
Net premiums earned$793,400$743,380$50,0206.7%

Gross premiums earned included earned premium from our acquisition of NORCAL of approximately $296.5 million in 2022 as compared to $226.0 million in 2021. Excluding NORCAL premiums, gross premiums earned decreased $30.6 million in 2022 as compared to 2021 driven by the pro rata effect of a reduction in net premiums written in our Lloyd's Syndicates business during the preceding twelve months, partially offset by our focus on rate adequacy.

Ceded premiums earned during both 2022 and 2021 included prior accident year ceded premium adjustments under swing rated reinsurance agreements. After removing the effect of prior accident year ceded premium adjustments from both years, ceded premiums earned decreased $11.1 million in 2022 as compared to 2021 driven by our decreased participation in the results of Syndicate 1729 and Syndicate 6131 for the 2021 underwriting year and a decrease in premium ceded under our shared risk arrangements during the preceding twelve months, partially offset by the pro rata effect of an increase in premium ceded under our excess of loss arrangements during the preceding twelve months.

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Losses and Loss Adjustment Expenses

The following table summarizes calendar year net loss ratios for our Specialty P&C segment by separating losses between the current accident year and all prior accident years. The net loss ratios for our Specialty P&C segment were as follows:

Net Loss Ratios (1)
Year Ended December 31
20222021Change
Calendar year net loss ratio78.9%81.4%(2.5pts)
Less impact of prior accident years on the net loss ratio(2.8%)(3.8%)1.0pts
Current accident year net loss ratio(2)81.7%85.2%(3.5pts)

(1)Net losses, as specified, divided by net premiums earned.

(2)For the year ended December 31, 2022, our current accident year net loss ratio (as shown in the table above), improved 3.5 percentage points as compared to 2021. The change in our current accident year net loss ratio was primarily attributable to the following:

(In percentage points)Increase (Decrease) 2022 versus 2021
Estimated ratio increase (decrease) attributable to:
Lloyd's Syndicates0.8 pts
NORCAL Operations(2.2 pts)
NORCAL Acquisition - Purchase Accounting Amortization0.3 pts
Change in Estimate of ULAE(3.3 pts)
Ceded Premium Adjustments, Prior Accident Years0.2 pts
All other, net0.8 pts
Decrease in current accident year net loss ratio(3.5 pts)

The following table shows the components of our net prior accident year reserve development:

Year Ended December 31
($ in thousands)20222021Change
Net favorable reserve development$11,667$20,324$(8,657)(42.6%)
NORCAL Acquisition - Purchase Accounting Amortization*10,8197,9072,91236.8%
Total net favorable reserve development$22,486$28,231$(5,745)(20.3%)
*See Note 2 of the Notes to Consolidated Financial Statements in our December 31, 2022 report on Form 10-K for additional information on the amortization of the NORCAL acquisition purchase accounting adjustments.

•Development recognized during 2022 principally related to accident years 2017 and 2020 through 2021. Net favorable prior accident year reserve development recognized in 2022 included favorable development related to NORCAL's 2021 accident year and, to a lesser extent, our Medical Technology Liability line of business. Net favorable prior accident year reserve development recognized in 2022 was partially offset by unfavorable reserve development in our Lloyd's Syndicates and HCPL (excluding NORCAL) lines of business. The unfavorable reserve development in our Lloyd's Syndicates business was driven by higher than expected losses and development on certain large claims, primarily catastrophe related losses. The HCPL unfavorable development was driven by higher than anticipated loss severity trends in select jurisdictions, which emerged primarily in the fourth quarter of 2022. We have not recognized any development related to NORCAL's accident years 2020 or prior since the date of acquisition on May 5, 2021 based on our comparison of expected loss emergence to actual loss emergence.

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Underwriting, Policy Acquisition and Operating Expenses

Our Specialty P&C segment underwriting, policy acquisition and operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20222021Change
DPAC amortization$97,757$76,635$21,12227.6%
Management fees4,7633,78198226.0%
Other underwriting and operating expenses97,28965,25132,03849.1%
Total$199,809$145,667$54,14237.2%

DPAC amortization for 2022 increased due to a higher amount of premiums written driven by our 2021 acquisition of NORCAL. Due to the NORCAL acquisition and application of GAAP purchase accounting rules, the level of DPAC amortization in 2021 was approximately $13.4 million lower than would have otherwise been recognized. Under these purchase accounting rules, the capitalized policy acquisition costs for policies written prior to the acquisition date were written off through purchase accounting on May 5, 2021 rather than being expensed pro rata over the remaining term of the associated policies. DPAC amortization associated with NORCAL policies in 2022 is approximately $1.0 million lower than would have otherwise been recognized for the period. The remaining increase in DPAC amortization for 2022 as compared to 2021 reflected an increase in agency commissions due to a higher volume of commissionable premium driven by NORCAL and an increase in compensation-related expenses driven by an increase in headcount due to the addition of NORCAL employees.

Other underwriting and operating expenses increased in 2022 primarily due to a revision to our process of estimating ULAE which resulted in approximately $25.4 million of expenses remaining in operating expenses instead of being allocated to net losses and loss adjustment expenses. As a result, this change in ULAE estimate had offsetting impacts to our loss and expense ratios during 2022 with no impact to our combined ratio or segment results. See additional discussion on this change in ULAE estimate in the previous section under the heading "Losses and Loss Adjustment Expenses." Excluding the impact of the change in ULAE, other underwriting and operating expenses increased in 2022 as compared to 2021. The increase in 2022 was primarily attributable to higher amounts accrued for performance-related incentive plans due to our improved performance metrics, an increase in professional fees, as well as certain one-time expenses of $3.9 million. The increase in professional fees in 2022 was primarily attributable to an increase in IT consulting fees. One-time expenses in 2022 were mainly comprised of one-time bonuses, accelerated depreciation associated with a decommissioned IT system, employee severance charges and lease exit costs.

Underwriting Expense Ratio (the Expense Ratio)

Our expense ratio for the Specialty P&C segment was as follows:

Year Ended December 31
20222021Change
Underwriting expense ratio25.2%19.6%5.6pts

The change in our expense ratio in 2022 as compared to 2021 was primarily attributable to the following:

(In percentage points)Increase (Decrease) 2022 versus 2021
Estimated ratio increase (decrease) attributable to:
Change in Net Premiums Earned and DPAC amortization0.2 pts
NORCAL DPAC Amortization - Prior Period Purchase Accounting Impact1.8 pts
Change in Estimate of ULAE3.3 pts
One-Time Expenses0.5 pts
All other, net(0.2 pts)
Increase in the underwriting expense ratio5.6 pts

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Segment Results - Corporate

As previously discussed under the heading "ProAssurance Overview," we reorganized our segment reporting in the third quarter of 2023. As a result, the investment results of assets solely allocated to our Lloyd's Syndicate operations and U.K. income taxes which were previously reported in our Lloyd’s Syndicates segment are now reported in our Corporate segment. All prior period segment information has been recast to conform to the current period presentation. See further information regarding our segments in Note 16 of the Notes to Consolidated Financial Statements.

Our Corporate segment includes our investment operations excluding those reported in our Segregated Portfolio Cell Reinsurance segment. In addition, this segment includes corporate expenses, interest expense, U.S. and U.K. income taxes and non-premium revenues generated outside of our insurance entities. Segment results for the year ended December 31, 2022 and 2021 exclude transaction-related costs as well as the associated income tax benefit and, for 2022, the change in fair value of contingent consideration related to the NORCAL acquisition as we do not consider these items in assessing the financial performance of the segment. For additional information on the NORCAL acquisition see Note 2 of the Notes to Consolidated Financial Statements in our December 31, 2022 report on Form 10-K. Segment results for our Corporate segment were net earnings of $17.3 million and $93.4 million for the years ended December 31, 2022 and 2021, respectively, and included the following:

Year Ended December 31
($ in thousands)20222021Change
Net investment income$94,943$69,708$25,23536.2%
Equity in earnings (loss) of unconsolidated subsidiaries$4,888$48,974$(44,086)(90.0%)
Net investment gains (losses)$(39,090)$20,230$(59,320)(293.2%)
Other income$6,198$5,531$66712.1%
Operating expense$34,733$26,641$8,09230.4%
Interest expense$20,372$19,719$6533.3%
Income tax expense (benefit)$(5,423)$4,651$(10,074)(216.6%)

Net Investment Income

Net investment income is primarily derived from the income earned by our fixed maturity securities and also includes dividend income from equity securities, income from our short-term and cash equivalent investments, earnings from other investments and increases in the cash surrender value of BOLI contracts, net of investment fees and expenses.

Net investment income (loss) by investment category was as follows:

Year Ended December 31
($ in thousands)20222021Change
Fixed maturities$92,626$73,352$19,27426.3%
Equities3,7062,5391,16746.0%
Short-term investments, including Other5,4141,9633,451175.8%
BOLI1,1412,699(1,558)(57.7%)
Investment fees and expenses(7,944)(10,845)2,901(26.7%)
Net investment income$94,943$69,708$25,23536.2%

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Net Investment Gains (Losses)

The following table provides detailed information regarding our net investment gains (losses).

Year Ended December 31
(In thousands)20222021
Total impairment losses
Corporate debt$(1,331)$
Asset-backed securities(441)
Portion of impairment losses recognized in other comprehensive income before taxes:
Asset-backed securities14
Net impairment losses recognized in earnings(1,758)
Gross realized gains, available-for-sale fixed maturities1,65713,892
Gross realized (losses), available-for-sale fixed maturities(3,245)(1,179)
Net realized gains (losses), trading fixed securities(155)(20)
Net realized gains (losses), equity investments(5,928)5,394
Net realized gains (losses), other investments(222)8,660
Change in unrealized holding gains (losses), trading fixed securities(613)(529)
Change in unrealized holding gains (losses), equity investments(18,483)(4,697)
Change in unrealized holding gains (losses), convertible securities, carried at fair value as a part of other investments(10,557)(1,701)
Other214410
Net investment gains (losses)$(39,090)$20,230

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FY 2022 10-K MD&A

SEC filing source: 0001875246-23-000003.

Extracted structurally from real Item 7 body heading to real Item 7A/8 boundary. Confidence: high. Filing date: 2023-02-27. Report date: 2022-12-31.

ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

The following discussion generally focuses on the change in financial condition, results of operations and cash flows for the year ended December 31, 2022 as compared to the year ended December 31, 2021 and should be read in conjunction with the Consolidated Financial Statements and Notes to those statements which accompany this report. For a full discussion of the changes in the financial condition, results of operations and cash flows for the year ended December 31, 2021 as compared to the year ended December 31, 2020, please refer to Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" section of ProAssurance's December 31, 2021 report on Form 10-K.

Throughout the discussion we use certain terms and abbreviations, which can be found in the Glossary of Terms and Acronyms at the beginning of this report. In addition, a glossary of insurance terms and phrases is available on the investor section of our website. Throughout the discussion, references to "ProAssurance," "PRA," "Company," "organization," "we," "us" and "our" refer to ProAssurance Corporation and its consolidated subsidiaries. The discussion contains certain forward-looking information that involves significant risks, assumptions and uncertainties. As discussed under the heading "Caution Regarding Forward-Looking Statements," our actual financial condition and results of operations could differ significantly from these forward-looking statements.

Enterprise Risk Management

As a property and casualty insurance provider, we are exposed to many risks stemming from both our insurance operations and the environments in which we operate. Since certain risks can be correlated with other risks, an event or a series of events can impact multiple areas of the Company simultaneously and have a material effect on the Company's results of operations, financial position and/or liquidity. In response to these exposures we have implemented an ERM program. Our ERM program consists of numerous processes and controls that have been designed by our senior management with oversight by our Board and implemented across our organization. We utilize our ERM program to identify potential risks from all aspects of our operations and to evaluate these risks in a manner that is both prudent and balanced. Our primary objective is to develop a risk appetite that creates and preserves value for all of our stakeholders.

Management Risk Oversight

We have a risk management framework that recognizes the risks inherent in our operating segments as well as the risks associated with the operations of our holding company that is overseen by our Chief Executive Officer. The risk management process is managed by corporate executives in each line of business who are responsible for our key risk areas, including adequacy of loss reserves; defense of claims and the litigation process; the quality of investments supporting our reserves and capital; compliance with regulatory and financial reporting requirements; concentration in our insurance lines of business; and information privacy and data security. Our Chief Executive Officer and members of executive management are responsible for identifying material risks associated with these and other risk areas and for establishing and monitoring risk management solutions that address levels of risk appetite and risk tolerance that are recommended by management and reviewed by the Board. Our internal auditing department is responsible for reviewing and testing these risk management solutions.

Board of Directors Role in Risk Oversight

The Board is responsible for ensuring that our ERM process is in place and functioning. It reviews the ERM process established by management and monitors the functioning of the process, including management’s assessment of the most significant enterprise-level risks identified in the ERM process.

The Audit Committee has the primary oversight responsibility for risks relating to financial reporting and cybersecurity. We have established lines of communication between the Audit Committee, our independent auditor, internal auditor and management that enable the Audit Committee to perform its oversight function.

ProAssurance Overview

ProAssurance Corporation is a holding company for property and casualty insurance companies. Our insurance subsidiaries provide professional liability insurance, liability insurance for medical technology and life sciences risks and workers' compensation insurance. We also provide capital to Syndicate 1729 at Lloyd's of London.

We operate in five segments which are based on our internal management reporting structure for which financial results are regularly evaluated by our CODM to determine resource allocation and assess operating performance: Specialty P&C, Workers' Compensation Insurance, Segregated Portfolio Cell Reinsurance, Lloyd's Syndicates and Corporate. Additional information on ProAssurance's five operating and reportable segments is included in Note 16 of the Notes to Consolidated Financial Statements, Part I and in the Segment Results sections herein that follow.

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Growth Opportunities and Outlook

Over the long-term we expect our growth to come primarily through controlled expansion of our existing operations. In addition, we may identify opportunities for growth through the acquisition of other insurers, service providers or books of business. On May 5, 2021, we completed our acquisition of NORCAL Insurance Company. The NORCAL acquisition continues to contribute to top line growth, representing approximately 27% of consolidated gross premiums written in 2022. We believe this transaction delivers strategic value through the acquisition of customers, talent, distribution partners and expanded geographic footprint and scale. This supports a national platform to deliver value to our customers, business partners and other stakeholders. See further discussion on the NORCAL acquisition in Note 2 of the Notes to Consolidated Financial Statements.

We operate in very competitive markets and face strong competition from other insurance companies for all of our insurance products. Our Specialty P&C segment includes our HCPL insurance which represents the largest product line in our consolidated gross premiums written (58% in 2022). The Specialty P&C segment also includes our Medical Technology Liability (4% in 2022) and Small Business Unit (9% in 2022) lines of business. The healthcare market in the U.S. is continuing to consolidate, which brings competitive challenges and opportunities. This consolidation initially took the form of hospitals acquiring physician practices and later the growth of physician groups owned by outside investors. As these trends continue, most physicians no longer practice medicine as owners of an independent practice. Large single and multi-specialty practices often operate in many states. Healthcare delivery settings are changing with the growth of retail delivery by allied healthcare professionals as well as physicians in distributed clinics, pharmacies, large consumer stores and online. These larger commercial enterprises have differing risk management needs from those in the traditional small physician practices. In response to these trends, we have enhanced our coverage offerings to fit the needs of combined hospital/physician entities, multi-state medical groups, telemedicine companies, miscellaneous facilities, allied healthcare professionals and self-insured entities even as we continue to service that portion of the market maintaining more traditional practice structures. Our Medical Technology Liability and Small Business Unit lines of business are less affected by these consolidation trends.

Our operations at Eastern, a provider of workers' compensation insurance, represents the second largest product line in our consolidated gross premiums written (22% in 2022, including alternative market premiums). The workers’ compensation market is highly competitive in our operating territories and multi-line insurers continue to leverage workers’ compensation in their product offerings, which has resulted in a reduction of new business writings. We believe our workers' compensation product offerings allow us to provide flexibility in offering solutions to our customers at a competitive price. In addition, we believe that our claims handling and risk management services are attractive to our customers and provide us with a competitive advantage even when our pricing is higher than our competitors, which has contributed to strong renewal retention.

Our Lloyd's Syndicates segment represents 2% of our consolidated gross premiums written in 2022. Our participation in Syndicate 1729 for the 2014 through 2022 underwriting years has ranged from a low of 5% to a high of 62%. For the 2023 underwriting year, our participation in the results of Syndicate 1729 remains unchanged at 5%.

We believe our emphasis on the fair treatment of our insureds and other important stakeholders through our commitment to “Treated Fairly” has enhanced our market position and differentiated us from other insurers. We will continue to uphold our values of integrity, leadership, relationships and enthusiasm in all of our activities. We will honor these values in the execution of “Treated Fairly” to perform our Mission and realize our Vision. We believe that as we reach more customers with this message we will continue to improve retention and add new insureds.

Key Performance Measures

We are committed to disciplined underwriting, pricing and loss reserving practices as well as an effective investment strategy, even during difficult market conditions. We are also committed to maintaining prudent operating and financial leverage. We recognize the importance that our customers and producers place on the financial strength of our insurance subsidiaries, and we manage our business to protect our financial security.

In evaluating our performance, we consider a number of performance measures, including the following:

•The net loss ratio which is calculated as net losses and loss adjustment expenses incurred divided by net premiums earned and is a component of underwriting profitability.

•The underwriting expense ratio which is calculated as underwriting, policy acquisition and operating expenses incurred divided by net premiums earned and is a component of underwriting profitability.

•The combined ratio which is the sum of the net loss ratio and the underwriting expense ratio and measures underwriting profitability.

•The investment income ratio which is calculated as net investment income divided by net premiums earned and measures the contribution investment earnings provide to our overall profitability.

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•The operating ratio which is the combined ratio, less the investment income ratio. This ratio provides the combined effect of underwriting profitability and investment income.

•The tax ratio which is calculated as total income tax expense (benefit) divided by income (loss) before income taxes and measures our effective tax rate.

•Non-GAAP operating income (loss) is widely used to evaluate performance within the insurance sector. In calculating Non-GAAP operating income (loss), we have excluded the effects of the items that do not reflect normal results, such as net investment gains (losses), transaction-related costs, the 2021 gain on bargain purchase and guaranty fund assessments. We believe Non-GAAP operating income (loss) presents a useful view of the performance of our insurance operations, however it should be considered in conjunction with net income (loss) computed in accordance with GAAP. See a reconciliation to its GAAP counterpart in the Executive Summary of Operations section under the heading “Non-GAAP Financial Measures” that follows.

•ROE which is calculated as net income (loss) divided by the average of beginning and ending shareholders’ equity. This ratio measures our overall after-tax profitability and shows how efficiently capital is being used.

•Non-GAAP operating ROE is calculated as Non-GAAP operating income (loss) for the period divided by the average of beginning and ending total GAAP shareholders’ equity. Non-GAAP operating ROE measures the overall after-tax profitability of our insurance operations and shows how efficiently capital is being used; however, it should be considered in conjunction with ROE computed in accordance with GAAP. See a reconciliation to its GAAP counterpart in the Executive Summary of Operations section under the heading “Non-GAAP Financial Measures” that follows.

•Book value per share which is calculated as total shareholders’ equity at the balance sheet date divided by the total number of common shares outstanding. This ratio measures the net worth of the Company to shareholders on a per-share basis. The declaration of dividends decreases book value per share. Growth in book value per share, adjusted for dividends declared, is an indicator of overall profitability.

•Non-GAAP adjusted book value per share is a Non-GAAP measure widely used within the insurance sector and is calculated as shareholders’ equity, excluding AOCI, divided by the total number of common shares outstanding at the balance sheet date. This Non-GAAP calculation measures the net worth of the Company to shareholders on a per share basis excluding AOCI to eliminate the temporary and potentially significant effects of fluctuations in interest rates on our fixed income portfolio; however, it should be considered in conjunction with book value per share computed in accordance with GAAP. See a reconciliation to its GAAP counterpart in the Executive Summary of Operations section under the heading “Non-GAAP Financial Measures” that follows.

In particular, we focus on our combined ratio and investment returns, both of which directly affect our ROE and growth in our book value. Currently, we target a dynamic long-term ROE of 700 basis points above the 10-year U.S. Treasury rate, which at December 31, 2022 was approximately 10.9%.

To achieve our long-term ROE target, we emphasize rate adequacy, selective underwriting, effective claims management, operational efficiency gained by leveraging our enhanced scope and scale and prudent investment management. We closely monitor premium revenues, losses and loss adjustment expenses, and underwriting and policy acquisition expenses. Our overall investment strategy is to focus on maximizing current income from our investment portfolio while maintaining appropriate credit risk, liquidity, duration, portfolio diversification and capital efficiency. While we engage in activities that generate other income, these activities, such as insurance agency services, do not constitute a significant use of our resources or a significant source of revenues or profits.

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Critical Accounting Estimates

Our Consolidated Financial Statements are prepared in conformity with GAAP. Preparation of these financial statements requires us to make estimates and assumptions that affect the amounts we report on those statements. We evaluate these estimates and assumptions on an ongoing basis based on current and historical developments, market conditions, industry trends and other information that we believe to be reasonable under the circumstances. We can make no assurance that actual results will conform to our estimates and assumptions; reported results of operations may be materially affected by changes in these estimates and assumptions.

Management considers the following accounting estimates to be critical because they involve significant judgment by management and those judgments could result in a material effect on our financial statements.

Reserve for Losses and Loss Adjustment Expenses

The largest component of our liabilities is our reserve for losses and loss adjustment expenses ("reserve for losses" or "reserve"), and the largest component of expense for our operations is incurred losses and loss adjustment expenses (also referred to as “losses and loss adjustment expenses,” “incurred losses,” “losses incurred” and “losses”). Incurred losses reported in any period reflect our estimate of losses incurred related to the premiums earned in that period as well as any changes to our previous estimate of the reserve required for prior periods.

As of December 31, 2022, our reserve is comprised almost entirely of long-tail exposures. The estimation of long-tailed losses is inherently complex and is subject to significant judgment on the part of management. Due to the nature of our claims, our loss costs, even for claims with similar characteristics, can vary significantly depending upon many factors, including but not limited to the specific characteristics of the claim and the manner in which the claim is resolved. Long-tailed insurance is characterized by the extended period of time typically required both to assess the viability of a claim and potential damages, if any, and to reach a resolution of the claim. The claims resolution process may extend to more than five years. Further, the industry has experienced new conditions, including the effect of the postponement of court cases and changes in settlement trends as a result of COVID-19. The combination of continually changing conditions and the extended time required for claim resolution results in a loss cost estimation process that requires actuarial skill and the application of significant judgment, and such estimates require periodic modification.

Our reserve is established by management after taking into consideration a variety of factors including premium rates, historical paid and incurred loss development trends and our evaluation of the current loss environment including frequency, severity, expected effects of monetary and social inflation, general economic and social trends, and the legal and political environment. The effect of COVID-19 on recent historical trends regarding timing and severity of claims may also impact certain of these factors and our ultimate estimation of losses. We also take into consideration the conclusions reached by our internal and consulting actuaries. We update and review the data underlying the estimation of our reserve for losses each reporting period and make adjustments to loss estimation assumptions that we believe best reflect emerging data. Both our internal and consulting actuaries perform an in-depth review of our reserve for losses on at least a semi-annual basis using the loss and exposure data of our insurance subsidiaries.

We partition our reserves by accident year, which is the year in which the claim becomes our liability. For claims-made policies, the insured event generally becomes a liability when the event is first reported to us. For occurrence policies, the insured event becomes a liability when the event takes place. For retroactive coverages, the insured event becomes a liability at inception of the underlying contract. As claims are incurred (reported) and claim payments are made, they are aggregated by accident year for analysis purposes. We also partition our reserves by reserve type: case reserves and IBNR reserves. Case reserves are established by our claims departments based upon the particular circumstances of each reported claim and represent our estimate of the future loss costs (often referred to as expected losses) that will be paid on reported claims. Case reserves are decremented as claim payments are made and are periodically adjusted upward or downward as estimates regarding the amount of future losses are revised; reported loss for an individual claim is the case reserve at any point in time plus the claim payments that have been made to date. IBNR reserves are estimated by accident year and represent our estimate in the aggregate of future development on losses that have been reported to us and our estimate of losses that have been incurred but not reported to us.

Our reserving process can be broadly grouped into three areas: the establishment of the reserve for the current accident year (the initial reserve), the re-estimation of the reserve for prior accident years (development of prior accident years) and the establishment of the initial reserve for risks assumed in business combinations, applicable only in periods in which acquisitions occur (the acquired reserve). A summary of the activity in our net reserve for losses during 2022 and 2021 is provided under the heading "Losses" in the Liquidity and Capital Resources and Financial Condition section that follows.

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Current Accident Year - Initial Reserve

Considerable judgment is required in establishing our initial reserve for any current accident year period, as there is limited data available upon which to base our estimate (see further discussion that follows under the heading "Use of Judgment"). Our process for setting an initial reserve considers the unique characteristics of each product, but in general we rely heavily on the loss assumptions that were used to price business, as our pricing reflects our analysis of loss costs that we expect to incur relative to the insurance product being priced.

Specialty P&C Segment. Loss costs within this segment are impacted by many factors including but not limited to the nature of the claim, including whether or not the claim is an individual or a mass tort claim, the personal situation of the claimant or the claimant's family, the outcome of jury trials, the legislative and judicial climate where any potential litigation may occur, general economic and social trends and the trend of healthcare costs. Within our Specialty P&C segment, for our professional liability business (88% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2022; predominately comprised of our HCPL products), we set an initial reserve based upon our evaluation of the current loss environment including frequency, severity, monetary inflation, social inflation and legal trends.

The current accident year net loss ratio in the Specialty P&C segment has ranged from 83% to 106% in the past five years. We observed a reduction in claims frequency that started to emerge in 2020, some of which was due to our re-underwriting efforts and some of which, we believe, was associated with the COVID-19 pandemic including the disruption of the court systems. Given the consistent and prolonged nature of these favorable trends, we recognized these favorable frequency trends in our HCPL current accident year reserve during the third and fourth quarters of 2021. Further, we reduced certain expected NORCAL loss ratios during the fourth quarter of 2021 and the third and fourth quarters of 2022 due to favorable frequency trends which, we believe, is primarily attributable to our re-underwriting efforts. While NORCAL claims frequency is generally down, we observed higher than anticipated loss emergence in our HCPL line of business in select jurisdictions, primarily in the Standard Physician line, which we recognized in our HCPL current accident year reserve during the fourth quarter of 2022. See further discussion in our Segment Results - Specialty Property & Casualty section that follows under the heading "Losses and Loss Adjustment Expenses."

The risks insured in our Medical Technology Liability business (2% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2022) are more varied, and policies are individually priced based on the risk characteristics of the policy and the account. The insured risks range from startup operations to large multinational entities, and the larger entities often have significant deductibles or self-insured retentions. Reserves are established using our most recently developed actuarial estimates of losses expected to be incurred based on factors which include results from prior analysis of similar business, industry indications, observed trends and judgment. Claims in this line of business primarily involve bodily injury to individuals and are affected by factors similar to those of our HCPL line of business. For the Medical Technology Liability business, we also establish an initial reserve using a loss ratio approach, including a provision in consideration of historical loss volatility that this line of business has exhibited.

Workers' Compensation Insurance Segment. Many factors affect the ultimate losses incurred for our workers' compensation coverages (5% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2022) including but not limited to the type and severity of the injury, the age, health and occupation of the injured worker, the estimated length of disability, medical treatment and related costs, and the jurisdiction and workers' compensation laws of the state of the injury occurrence.

We use various actuarial methodologies in developing our workers’ compensation reserve, combined with a review of the payroll exposure base. For the current accident year, given the lack of seasoned information, the different actuarial methodologies produce results with significant variability; therefore, more emphasis is placed on supplementing results from the actuarial methodologies with trends in exposure base, medical expense inflation, general inflation, severity, and claim counts, among other things, to select an ultimate loss indication.

The current accident year net loss ratio in the Workers' Compensation Insurance segment was 71.8% in 2022, which was lower than the 2021 loss ratio of 74.0%, reflecting improved claim frequency and severity trends. The current accident year net loss ratio in 2021 reflected higher claim activity as workers returned to employment with the easing of pandemic-related restrictions in our operating territories, including the impact of labor shortages on the existing workforce.

Segregated Portfolio Cell Reinsurance Segment. The factors that affect the ultimate losses incurred for the workers' compensation and HCPL coverages assumed by the SPCs at Inova Re and Eastern Re (2% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2022) are consistent with that of our Workers’ Compensation Insurance and Specialty P&C segments, respectively.

Lloyd's Syndicates Segment. Initial reserves for Syndicate 1729 are primarily recorded using the loss assumptions by risk category incorporated into the Syndicate's business plan submitted to Lloyd's with consideration given to loss experience incurred to date (3% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2022). The assumptions used in each business plan are consistent with loss results reflected in Lloyd's historical data for similar risks. The

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loss ratio may also fluctuate due to the mix of earned premium from different open underwriting years which we participate in to varying degrees, as well as the timing of earned premium adjustments. Such adjustments may be the result of premiums for certain policies and assumed reinsurance contracts being reported subsequent to the coverage period and may be subject to adjustment based on loss experience. Premium and exposure for some of Syndicate 1729's insurance policies and reinsurance contracts are initially estimated and subsequently recorded over an extended period of time as reports are received under delegated underwriting authority programs. When reports are received, the premium, exposure and corresponding loss estimates are revised accordingly. Changes in loss estimates due to premium or exposure fluctuations are incurred in the accident year in which the premium is earned.

For significant property catastrophe exposures, Syndicate 1729 uses third-party catastrophe models to accumulate a listing of potentially affected policies. Each identified policy is given an estimate of loss severity based upon a combination of factors including the probable maximum loss of each policy, market share analytics, underwriting judgment, client/broker estimates and historical loss trends for similar events. These models are inherently uncertain, reliant upon key assumptions and management judgment and are not always a representation of actual events and ensuing potential loss exposure. Determination of actual losses may take an extended period of time until claims are reported and resolved, including coverage litigation.

Development of Prior Accident Years

In addition to setting the initial reserve for the current accident year, we reassess the amount of reserve required for prior accident years each period.

The foundation of our reserve re-estimation process is an actuarial analysis that is performed by both our internal and consulting actuaries. This very detailed analysis projects ultimate losses based on partitions which include line of business, geography, coverage layer and accident year. The procedure uses the most representative data for each partition, capturing its unique patterns of development and trends. We believe that the use of consulting actuaries provides an independent view of our loss data as well as a broader perspective on industry loss trends.

For the Specialty P&C, Workers' Compensation Insurance and Segregated Portfolio Cell Reinsurance segments, the analysis performed by the consulting actuaries analyzes each partition of our business in a variety of ways and uses multiple actuarial methodologies in performing these analyses, including:

•Bornhuetter-Ferguson (Paid and Reported) Method

•Paid Development Method

•Reported (Incurred) Development Method

•Average Paid Value Method

•Average Reported Value Method

A brief description of each method follows.

Bornhuetter-Ferguson Method. We use both the Paid and the Reported Bornhuetter-Ferguson Methods. The Paid Method assigns partial weight to initial expected losses for each accident year (initial expected losses being the first established case and IBNR reserves for a specific accident year) and partial weight to paid to date losses. The Reported Method assigns partial weight to the initial expected losses and partial weight to current reported losses. The weights assigned to the initial expected losses decrease as the accident year matures.

Paid Development and Reported (Incurred) Development Methods. These methods use historical, cumulative losses (paid losses for the Paid Development Method, reported losses for the Reported (Incurred) Development Method) by accident year and develop those actual losses to estimated ultimate losses based upon the assumption that each accident year will develop to estimated ultimate cost in a manner that is analogous to prior years, adjusted as deemed appropriate for the expected effects of known changes in the claim payment environment (and case reserving environment for the Reported (Incurred) Development Method); and to the extent necessary, supplemented by analyses of the development of broader industry data.

Average Paid Value and Average Reported Value Methods. In these methods, average claim cost data (paid claim cost for the Average Paid Value Method and reported claim cost for the Reported Value Method) is developed to an ultimate average cost level by report year based on historical data. Claim counts are similarly developed to an ultimate count level. The average claim cost (after rounding and adjustment, if necessary, to accommodate report year data that is not considered to be predictive) is then multiplied by the ultimate claim counts by report year to derive ultimate loss and ALAE.

Generally, methods such as the Bornhuetter-Ferguson Method are used on more recent accident years where we have less data on which to base our analysis. As time progresses and we have an increased amount of data for a given accident year, we begin to give more confidence to the development and average methods, as these methods typically rely more heavily on our own historical data. These methods emphasize different aspects of loss reserve estimation and provide a variety of perspectives for our decisions.

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Certain of the methodologies utilized to estimate the ultimate losses for each partition of our reserves consider the actual amounts paid. Paid data is particularly influential when a large portion of known claims have been closed, as is the case for older accident years. In selecting a point estimate for each partition, management considers the extent to which trends are emerging consistently for all partitions and known industry trends. Thus, actual, rather than estimated severity trends are given more consideration. If actual severity trends are lower than those estimated at the time that reserves were previously established, the recognition of favorable development is indicated. This is particularly true for older accident years where our actuarial methodologies give more weight to actual loss costs (severity).

The various actuarial methods discussed above are applied in a consistent manner from period to period. In addition, we perform statistical reviews of claims data such as claim counts, average settlement costs and severity trends when establishing our reserves.

We utilize the selected point estimates of ultimate losses to develop estimates of ultimate losses recoverable from reinsurers, based on the terms and conditions of our reinsurance agreements. An overall estimate of the amount receivable from reinsurers is determined by combining the individual estimates. Our net reserve estimate is the gross reserve point estimate less the estimated reinsurance recovery.

For our Workers’ Compensation Insurance segment and for the workers' compensation exposures in our Segregated Portfolio Cell Reinsurance segment, we utilize the Reported (Incurred) Development Method, Paid Development Method and Bornhuetter-Ferguson Method, to develop our reserve for each accident year. The actuarial review includes the stratification of claims data (lost time claims, medical only claims) using different variations that allow us to identify trends that may not be readily identifiable if the data was evaluated only in the aggregate. Reported and paid loss development factors are key assumptions in the reserve estimation process and are based on our historical reported and paid loss development patterns. As accident years mature, the various actuarial methodologies produce more consistent loss estimates.

For our Lloyd's Syndicates segment we rely on the analysis of actual loss experience on the book of business written by Syndicate 1729 to determine loss development by accident year.

Acquired Reserve

The acquisition of NORCAL on May 5, 2021 increased our gross reserves by $1.2 billion which was the fair value of NORCAL's gross loss reserve at the time of acquisition. The fair value estimate of NORCAL's gross reserve for losses and loss adjustment expenses was based on three components: an actuarial estimate of the expected future net cash flows, a reduction to those cash flows for the time value of money determined utilizing the U.S. Treasury Yield Curve and a risk margin adjustment to reflect the net present value of profit that an investor would demand in return for the assumption of the development risk associated with the reserve. The fair value of NORCAL's gross reserve, including the risk margin adjustment, exceeded the actuarial estimate of NORCAL’s undiscounted gross loss reserve by approximately $42.2 million as of May 5, 2021. This fair value adjustment was recorded to the reserve for losses and loss adjustment expenses and will be amortized over a period utilizing loss payment patterns as a reduction to prior accident year net losses and loss adjustment expenses. We also recorded other adjustments to NORCAL’s reserve as a result of purchase accounting including negative VOBA on NORCAL’s assumed unearned premium and assumed DDR reserve. See further discussion on these other purchase accounting adjustments in Note 2 of the Notes to Consolidated Financial Statements.

Use of Judgment

The process of estimating reserves involves a high degree of judgment and is subject to a number of variables. These variables can be affected by both views of internal and external events, such as changes in views of monetary and social inflation, legal trends and legislative changes, as well as differentiating views of individuals involved in the reserve estimation process, among others. We continually refine our estimates in a regular, ongoing process as historical loss experience develops and additional claims are reported and settled. Our objective is to consider all significant facts and circumstances known at the time.

Our loss reserves may be impacted by social inflation, which is generally described as the rising costs of insurance claims resulting from factors including, but not limited to, increasing litigation, broader definitions of liability, more plaintiff-friendly legal decisions, jury behavior, and larger compensatory jury awards and non-economic damages. These factors could lead to greater than anticipated claims and claim handling expenses which could exceed our established reserves causing us to increase our loss reserves.

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The effects of monetary inflation could cause the cost of claims to rise in the future. Our loss reserves include assumptions about future payments for settlement of claims and claims handling expenses, such as medical treatments and litigation costs. To the extent inflation causes these costs to increase above reserves established for these claims, we will be required to increase our loss reserves with a corresponding reduction in our financial results in the period in which the need for additional reserves is identified.

We use various actuarial methods in the process of setting reserves. Each actuarial method generally returns a different value, and for the more recent accident years the variations among the various methodologies can be significant. In order to project ultimate losses, we partition our reserves for analysis such as by line of business, geography, coverage layer or accident year. For each partition of our reserves, we evaluate the results of the various methods, along with the supplementary statistical data regarding such factors as closed with and without indemnity ratios, claim severity trends, the expected duration of such trends, changes in the legal and legislative environment and the current economic environment to develop a point estimate based upon management's judgment and past experience. The series of selected point estimates is then combined to produce an overall point estimate for ultimate losses.

HCPL. Over the past several years the most influential factor affecting the analysis of our HCPL reserves and the related development recognized has been an observed increase in claim severity for the broader medical professional liability industry as well as higher initial loss expectations on incurred claims. The severity trend is an explicit component of our pricing models and directly impacts the reserving process. Our estimate of this trend and our expectations about changes in this trend impact a variety of factors, from the selection of expected loss ratios to the ultimate point estimates established by management.

Because of the implicit and wide-ranging nature of severity trend assumptions on the loss reserving process, it is not practical to specifically isolate the impact of changing severity trends. However, because severity is an explicit component of our HCPL pricing process we can better isolate the impact that changing severity can have on our loss costs and loss ratios in regards to our pricing models for this business component. Our current HCPL pricing models assume severity trends in the range of 2% to 6% depending on state, territory and specialty. In some portions of our HCPL business we have observed and reflected higher severity trends in our estimates of losses and loss adjustment expenses.

Due to the long-tailed nature of our claims and the previously discussed historical volatility of loss costs, selection of a severity trend assumption is a subjective process that is inherently likely to prove inaccurate over time. Given the long tail and volatility, we are generally cautious in making changes to the severity assumptions within our pricing models. All open claims and accident years are generally impacted by a change in the severity trend, which compounds the effect of such a change.

Although the future degree and impact of the ultimate severity trend remains uncertain due to the long-tailed nature of our business, we have given consideration to observed loss costs in setting our rates. For our HCPL business, this practice had generally resulted in rate reductions as claim frequency declined and remained at historically low levels. However, from early 2017 to the current period, the average pricing on renewed business has steadily increased reflective of the rising loss cost environment, and we anticipate further renewal pricing increases due to increasing loss severity.

Another factor affecting our analysis of our HCPL reserves and the related development recognized is the reduction in claims frequency that started to emerge in 2020, some of which was due to our re-underwriting efforts and some of which, we believe, was associated with the COVID-19 pandemic, as previously discussed. In 2020, we established a $10 million IBNR reserve related to COVID-19. Given the consistent and prolonged nature of the favorable claims frequency trend and the fact that early first notices of potential claims related to anticipated COVID-19 losses have not turned into claims, we reduced our COVID-19 IBNR reserve by $9 million and $1 million in 2022 and 2021, respectively. As of December 31, 2022, we no longer carry a specific IBNR reserve for potential COVID-19 related losses.

Workers' Compensation. The projection of changes in claim severity trend has not historically been an influential factor affecting our analysis of workers' compensation reserves, as claims are typically resolved more quickly than the industry norm. As previously mentioned, the determination and calculation of loss development factors requires considerable judgment.

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Loss Development by Line of Business

Professional Liability

Our professional liability line of business includes both our HCPL and Small Business Unit lines, with our HCPL line representing the largest component of our reserve. Our HCPL line of business also includes the business acquired through the NORCAL transaction that closed on May 5, 2021. In support of our concern that the decline in frequency will result in a higher severity trend for our HCPL claims (suits), we saw our closed-with-indemnity-payment ratio (i.e., the number of suits closed with an indemnity or loss payment as compared to the total number of closed suits) for our claims increase from 28% in 2015 to 33% in 2022.

The following table presents additional information about the loss development for our professional liability line of business, excluding loss development for HCPL coverages assumed by the SPCs at Inova Re and Eastern Re. Furthermore, loss development for our professional liability line of business for the year ended December 31, 2022 includes NORCAL and the year ended December 31, 2021 includes NORCAL since the date of acquisition, excluding the amortization of the purchase accounting fair value adjustment in each period:

($ in thousands)202220212020
Accident YearsEstimated Ultimate Losses, Net of Reinsurance, December 31, 2022Reserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims Closed
2022$606,906N/A26.9%N/AN/AN/AN/A
2021$708,733$(5,754)52.9%N/A25.9%N/AN/A
2020$802,923$(17,597)66.7%$(4,947)54.1%N/A22.0%
2019$840,353$20,28583.5%$(20,426)73.7%$1,36148.7%
2018$821,716$4,49189.5%$9,41881.0%$1,21865.1%
2017$699,144$(10,261)93.3%$(2,342)88.4%$(2,741)77.9%
2016$712,692$1,64291.0%$(2,739)89.5%$(1,760)88.8%
2015$638,344$5,19098.1%$6,01197.1%$(4,489)93.7%
2014$567,219$(1,266)99.0%$(1,017)98.5%$(8,930)96.6%
2013$587,169$(2,608)99.3%$(260)98.9%$(133)98.0%
Prior to 2013$8,975,275$(8,123)$(610)$(3,413)

•Development recognized during 2022 principally related to accident years 2017, 2020 and 2021. Net favorable development recognized in 2022 included favorable development related to NORCAL's 2021 accident year. We have not recognized any development related to NORCAL's accident years 2020 or prior since the date of acquisition on May 5, 2021 based on our comparison of expected loss emergence to actual loss emergence. Net favorable prior accident year reserve development recognized in 2022 was partially offset by unfavorable development recognized in our HCPL line of business, excluding NORCAL, driven by higher than anticipated loss severity trends, which emerged primarily in the fourth quarter of 2022. In addition, we recognized favorable prior year reserve development of $9.0 million in 2022 related to the 2020 accident year associated with our COVID-19 IBNR reserve, as previously discussed, due to the fact that early first notices of potential claims have not turned into claims.

•Development recognized during 2021 principally related to accident years 2015 through 2020. We also recognized favorable prior year reserve development of $1.0 million associated with our COVID-19 IBNR reserve.

•Development recognized during 2020 principally related to accident years 2014 through 2017.

•Not included in the table above, is $10.8 million and $7.9 million of amortization of the purchase accounting fair value adjustment on NORCAL's assumed net reserve and amortization of the negative VOBA associated with NORCAL's DDR reserve which is recorded as a reduction to prior accident year net losses and loss adjustment expenses in 2022 and 2021, respectively. See Note 2 of the Notes to Consolidated Financial Statements for additional information on the NORCAL acquisition and the related purchase accounting adjustments.

•Not included in the above table, as previously discussed, is $0.7 million of unfavorable development recognized in 2022 and $2.5 million and $4.4 million of favorable development recognized during 2021 and 2020, respectively, in our Segregated Portfolio Cell Reinsurance segment related to the HCPL coverages assumed by the SPCs at Inova Re and Eastern Re.

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This can also be seen in looking at both the absolute amount of reserve development recognized for the less developed accident years as well as the size of such development when compared to established ultimates for those same accident years at the end of the preceding calendar year. The following table provides this information for years ended December 31, 2022, 2021 and 2020 with respect to the three then most recent prior accident years:

($ in millions)202220212020
Prior accident years2019-20212018-20202017-2019
Net favorable (unfavorable) development recognized for the specified years$3.1$16.0$0.2
Development as a % of established ultimates, prior calendar year end0.1%1.1%%

Medical Technology Liability

Our Medical Technology Liability line of business has not experienced the change in claims frequency previously described for HCPL. However, the nature of the risks insured and volatility of the loss experience in this line of business has produced more variable loss development, as presented in the following table:

($ in thousands)202220212020
Accident YearsEstimated Ultimate Losses, Net of Reinsurance, December 31, 2022Reserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims Closed
2022$17,683N/A16.8%N/AN/AN/AN/A
2021$14,145$(2,759)53.3%N/A32.0%N/AN/A
2020$12,568$(1,921)70.6%$(248)59.2%N/A41.0%
2019$12,247$(1,337)55.3%$72247.5%$(1,047)41.8%
2018$8,554$(252)86.4%$(3,091)85.1%$(352)75.2%
2017$7,967$1,95097.1%$(2,192)94.1%$(3,854)90.1%
2016$9,146$53598.4%$(2,126)97.3%$(486)96.7%
2015$7,216$(767)97.6%$(638)97.0%$(663)96.3%
2014$9,130$(244)99.6%$(317)99.6%$(458)98.9%
2013$4,550$(49)100.0%$(128)100.0%$(294)100.0%
Prior to 2013$593,349$(156)$(106)$(1,439)

•Approximately $6.3 million of the $5.0 million total net favorable development recognized in 2022 related to the 2018 through 2021 accident years. The development for the 2018 through 2021 accident years represents a 11.7% reduction to the ultimates established for those reserves at December 31, 2021.

•Approximately $7.6 million of the $8.1 million total net favorable development recognized in 2021 related to the 2015 through 2020 accident years. The development for the 2015 through 2020 accident years represents a 11.3% reduction to the ultimates established for those reserves at December 31, 2020.

•Approximately $5.3 million of the $8.6 million total net favorable development recognized in 2020 related to the 2017 through 2019 accident years. The development for the 2017 through 2019 accident years represents a 13.7% reduction to the ultimates established for those reserves at December 31, 2019.

•In 2022, 2021 and 2020 the development was largely attributable to favorable results from claims closed during the year. As time has elapsed we have recognized that actual loss experience has on average been better than estimated. We have been cautious in recognizing the improvement, but as claims have matured and claims are closed or have become more certain for the remaining open claims, we have revised reserve estimates. We believe the need for a cautious approach is required as outcomes are uncertain and results can be significantly affected by outcomes for a small number of cases.

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Workers' Compensation

Claims in our workers’ compensation line of business have historically closed at a faster rate than in our HCPL or Medical Technology Liability lines of business. This faster disposition rate, along with a lower net retention after the application of reinsurance, has resulted in less volatility in loss estimates on a net basis. However, a change in the number of individually-severe claims can create volatility in a given accident year. The following table presents additional information about the loss development for our workers' compensation line of business:

($ in thousands)202220212020
Accident YearsEstimated Ultimate Losses, Net of Reinsurance, December 31, 2022Reserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims Closed
2022$142,653N/A39.8%N/AN/AN/AN/A
2021$145,907$67582.6%N/A45.4%N/AN/A
2020$137,728$(3,348)93.8%$(1,493)85.1%N/A41.6%
2019$150,023$(4,143)96.2%$(4,030)92.1%$(6,160)81.6%
2018$159,152$(410)97.2%$(1,503)95.2%$58491.7%
2017$126,325$(3,209)98.2%$(2,375)97.3%$(3,372)96.0%
2016$107,606$(2,179)98.5%$(1,230)97.8%$(3,048)97.1%
2015$116,277$(1,285)98.9%$(1,538)98.4%$(3,919)98.0%
2014$117,001$(891)99.4%$(873)99.3%$(2,136)98.9%
2013$114,003$(377)99.6%$(646)99.5%$(592)99.5%
Prior to 2013$657,225$161$(1,032)$(529)

•In 2022, we recognized $8.0 million of net favorable development in our Workers' Compensation Insurance segment and $7.0 million of net favorable development in our Segregated Portfolio Cell Reinsurance segment related to workers' compensation business.

•In 2021, we recognized $7.6 million of net favorable development in our Segregated Portfolio Cell Reinsurance segment related to workers' compensation business and $7.1 million of net favorable development in our Workers' Compensation Insurance segment.

•In 2020, we recognized $12.1 million of net favorable development in our Segregated Portfolio Cell Reinsurance segment related to workers' compensation business, and $7.0 million of net favorable development in our Workers' Compensation Insurance segment.

Variability of Loss Reserves

As previously noted, the number of data points and variables considered and the subjective process followed in establishing our loss reserve makes it impractical to isolate individual variables and demonstrate their impact on our estimate of loss reserves. However, to provide a better understanding of the potential variability in our reserves, we have modeled implied reserve ranges around our single point net reserve estimates for our various lines of business assuming different confidence levels. The ranges have been developed by aggregating the expected volatility of losses across partitions of our business to obtain a consolidated distribution of potential reserve outcomes. The aggregation of this data takes into consideration correlations among our geographic and specialty mix of business. The result of the correlation approach to aggregation is that the ranges are narrower than the sum of the ranges determined for each partition.

We have used this modeled statistical distribution to calculate an 80% and 60% confidence interval for the potential outcome of our consolidated net reserve for losses. The high and low end points of the distributions are as follows:

Low End PointCarried Net ReserveHigh End Point
80% Confidence Level$2.197 billion$3.039 billion$4.027 billion
60% Confidence Level$2.413 billion$3.039 billion$3.583 billion

Any change in our estimate of net ultimate losses for prior years is reflected in net income (loss) in the period in which such changes are made.

Due to the size of our consolidated reserve for losses and the large number of claims outstanding at any point in time, even a small percentage adjustment to our total reserve estimate could have a material effect on our results of operations for the period in which the adjustment is made, as was the case in 2022, 2021 and 2020.

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Reinsurance

We use insurance and reinsurance (collectively, “reinsurance”) to provide capacity to write larger limits of liability, to provide reimbursement for losses incurred under the higher limit coverages we offer, to provide protection against losses in excess of policy limits and, in the case of risk sharing arrangements, to align our objectives with those of our strategic business partners and to provide custom insurance solutions for large customer groups. The purchase of reinsurance does not relieve us from the ultimate risk on our policies; however, it does provide reimbursement for certain losses we pay.

We make a determination of the amount of insurance risk we choose to retain based upon numerous factors, including our risk tolerance and the capital we have to support it, the price and availability of reinsurance, the volume of business, our level of experience with a particular set of exposures and our analysis of the potential underwriting results. We purchase excess of loss reinsurance to limit the amount of risk we retain and we do so from a number of companies to mitigate concentrations of credit risk. As of December 31, 2022, there is no reinsurer, on an individual basis, for which our recoverables for both paid and unpaid claims (net of amounts due to the reinsurer) and our prepaid balances are more than $55 million, in the aggregate. We utilize reinsurance brokers to assist us in the placement of these reinsurance programs and in the analysis of the credit quality of our reinsurers. The determination of which reinsurers we choose to do business with is based upon an evaluation of their then current financial strength, rating, stability and claims payment practices.

We evaluate each of our ceded reinsurance contracts at inception to confirm that there is sufficient risk transfer to allow the contract to be accounted for as reinsurance under current accounting guidance. At December 31, 2022, all ceded contracts were accounted for as risk transferring contracts.

Our receivable from reinsurers on unpaid losses and loss adjustment expenses represents our estimate of the amount of our reserve for losses that will be recoverable under our reinsurance programs. We base our estimate of funds recoverable upon our expectation of ultimate losses and the portion of those losses that we estimate to be allocable to reinsurers based upon the terms and conditions of our reinsurance agreements. Our assessment of the collectability of the recorded amounts receivable from reinsurers considers the payment history of the reinsurer, publicly available financial and rating agency data, our interpretation of the underlying contracts and policies and responses by reinsurers.

Given the uncertainty inherent in our estimates of losses and related amounts recoverable from reinsurers, these estimates may vary significantly from the ultimate outcome.

Under the terms of certain of our reinsurance agreements, the amount of premium that we cede to our reinsurers is based in part on the losses we recover under the agreements. Therefore, we make an estimate of premiums ceded under these reinsurance agreements subject to certain minimums and maximums. Any adjustments to our estimates of losses recoverable under our reinsurance agreements or the premiums owed under our agreements are reflected in current operations. Due to the size of our reinsurance balances, an adjustment to these estimates could have a material effect on our results of operations for the period in which the adjustment is made.

Our reinsurance receivables are exposed to credit losses but to date have not experienced any significant amount of credit losses. To partially mitigate our exposure to credit losses, reinsurance receivables totaling approximately $90.6 million were collateralized by letters of credit or funds withheld as of December 31, 2022. We measure expected credit losses on our reinsurance receivables on a collective basis when similar risk characteristics exist or on an individual basis if we determine a receivable does not share similar risk characteristics. We measure expected credit losses associated with our reinsurance receivables (related to both paid and unpaid losses) at the consolidated level as our reinsurance receivables share similar risk characteristics including type of financial asset, type of industry and similar historical and expected credit loss patterns. We measure expected credit losses over the average contractual term of our reinsurance receivables utilizing a loss rate method. Historical internal credit loss experience is the basis for our assessment of expected credit losses; however, we may also consider historical credit loss information from external sources. We also consider reasonable and supportable forecasts of future economic conditions in our estimate of expected credit losses. Expected credit losses associated with our reinsurance receivables (related to both paid and unpaid losses) were nominal in amount as of December 31, 2022 and 2021. No reinsurance balances were written off for credit reasons during the years ended December 31, 2022 or 2021. Should our expected credit loss analysis or other facts or circumstances lead us to believe that any reinsurer may not meet its obligations to us, adjustments to the allowance for expected credit losses or to reinsurance receivables would be reflected in current operations. Such an adjustment has the potential to be material to the results of operations in the period in which it is recorded; however, we would not expect such an adjustment to have a material effect on our capital position or our liquidity. For further information on our allowance for expected credit losses related to our receivables from reinsurers see Note 1 of the Notes to Consolidated Financial Statements.

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Investment Valuations

We record the majority of our investments at fair value as shown in the table below. At December 31, 2022, the distribution of our investments based on GAAP fair value hierarchies (levels) was as follows:

Distribution by GAAP Fair Value Hierarchy
Level 1Level 2Level 3Not CategorizedTotal Investments
Investments recorded at:
Fair value7%82%2%6%97%
Other valuations3%
Total Investments100%

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. All of our fixed maturity and equity investments are carried at fair value. The fair value of our short-term securities approximates the cost of the securities due to their short-term nature.

Because of the number of securities we own and the complexity of developing accurate fair values, we utilize multiple independent pricing services to assist us in establishing the fair value of individual securities. The pricing services provide fair values based on exchange-traded prices, if available. If an exchange-traded price is not available, the pricing services, if possible, provide a fair value that is based on multiple broker/dealer quotes or that has been developed using pricing models. Pricing models vary by asset class and utilize currently available market data for securities comparable to ours to estimate a fair value for our securities. The pricing services scrutinize market data for consistency with other relevant market information before including the data in the pricing models. The pricing services disclose the types of pricing models used and the inputs used for each asset class. Determining fair values using these pricing models requires the use of judgment to identify appropriate comparable securities and to choose a valuation methodology that is appropriate for the asset class and available data.

The pricing services provide a single value per instrument quoted. We review the values provided for reasonableness each quarter by comparing market yields generated by the supplied value versus market yields observed in the marketplace. We also compare yields indicated by the provided values to appropriate benchmark yields and review for values that are unchanged or that reflect an unanticipated variation as compared to prior period values. We utilize a primary pricing service for each security type and compare provided information for consistency with alternate pricing services, known market data and information from our own trades, considering both values and valuation trends. We also review weekly trades versus the prices supplied by the services. If a supplied value appears unreasonable, we discuss the valuation in question with the pricing service and make adjustments if deemed necessary. Historically our review has not resulted in any material changes to the values supplied by the pricing services. The pricing services do not provide a fair value unless an exchange-traded price or multiple observable inputs are available. As a result, the pricing services may provide a fair value for a security in some periods but not others, depending upon the level of recent market activity for the security or comparable securities.

Level 1 Investments

Fair values for a majority of our equity securities and portions of our short-term and convertible securities are determined using exchange-traded prices. There is little judgment involved when fair value is determined using an exchange-traded price. In accordance with GAAP, we classify securities valued using an exchange-traded price as Level 1 securities.

Level 2 Investments

Most fixed income securities do not trade daily; thus, exchange-traded prices are generally not available for these securities. However, market information (often referred to as observable inputs or market data, including but not limited to, last reported trade, non-binding broker quotes, bids, benchmark yield curves, issuer spreads, two-sided markets, benchmark securities, offers and recent data regarding assumed prepayment speeds, cash flow and loan performance data) is available for most of our fixed income securities. We determine fair value for a large portion of our fixed income securities using available market information. In accordance with GAAP, we classify securities valued based on multiple market observable inputs as Level 2 securities.

Level 3 Investments

When a pricing service does not provide a value for one of our fixed maturity securities, management estimates fair value using either a single non-binding broker quote or pricing models that utilize market based assumptions which have limited observable inputs. The process involves significant judgment in selecting the appropriate data and modeling techniques to use in the valuation process. In accordance with GAAP, we classify securities valued using limited observable inputs as Level 3 securities.

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Fair Values Not Categorized

We hold interests in certain investment funds, primarily LPs/LLCs, which measure fund assets at fair value on a recurring basis and provide us with a NAV for our interest. As a practical expedient, we consider the NAV provided to approximate the fair value of the interest. In accordance with GAAP, we do not categorize these investments within the fair value hierarchy.

Nonrecurring Fair Value Measurements

We measure the fair value of certain assets on a nonrecurring basis when events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. These assets include investments carried principally at cost, investments in tax credit partnerships, fixed assets, goodwill and other intangible assets. These assets would also include any equity method investments that do not provide a NAV. We did not have any assets or liabilities that were measured at fair value on a nonrecurring basis at December 31, 2022 or December 31, 2021.

Investments - Other Valuation Methodologies

Certain of our investments, in accordance with GAAP for the type of investment, are measured using methodologies other than fair value. At December 31, 2022, these investments represented approximately 3% of total investments, and are detailed in the following table. Additional information about these investments is provided in Note 3 and Note 4 of the Notes to Consolidated Financial Statements.

(In millions)Carrying ValueGAAP Measurement Method
Other investments:
Other, principally FHLB capital stock$3.3Principally Cost
Investment in unconsolidated subsidiaries:
Investments in tax credit partnerships4.1Equity
Equity method investments, primarily LPs/LLCs38.6Equity
42.7
BOLI81.7Cash surrender value
Total investments - Other valuation methodologies$127.7

Impairments

We evaluate our available-for-sale investment securities, which at December 31, 2022 and December 31, 2021 consisted entirely of fixed maturity securities, on at least a quarterly basis for the purpose of determining whether declines in fair value below recorded cost basis represent an impairment loss. We consider a credit-related impairment loss to have occurred:

•if there is intent to sell the security;

•if it is more likely than not that the security will be required to be sold before full recovery of its amortized cost basis; or

•if the entire amortized basis of the security is not expected to be recovered.

The assessment of whether the amortized cost basis of a security is expected to be recovered requires management to make assumptions regarding various matters affecting future cash flows. The choice of assumptions is subjective and requires the use of judgment. Actual credit losses experienced in future periods may differ from management’s current estimates of those credit losses. Methodologies used to estimate the present value of expected cash flows are:

The estimate of expected cash flows is determined by projecting a recovery value and a recovery time frame and assessing whether further principal and interest will be received. We consider various factors in projecting recovery values and recovery time frames, including the following:

•third-party research and credit rating reports;

•the current credit standing of the issuer, including credit rating downgrades, whether before or after the balance sheet date;

•the extent to which the decline in fair value is attributable to credit risk specifically associated with the security or its issuer;

•internal assessments and the assessments of external portfolio managers regarding specific circumstances surrounding an investment, which indicate the investment is more or less likely to recover its amortized cost than other investments with a similar structure;

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•for asset-backed securities, the origination date of the underlying loans, the remaining average life, the probability that credit performance of the underlying loans will deteriorate in the future and our assessment of the quality of the collateral underlying the loan;

•failure of the issuer of the security to make scheduled interest or principal payments;

•any changes to the rating of the security by a rating agency;

•recoveries or additional declines in fair value subsequent to the balance sheet date;

•adverse legal or regulatory events;

•significant deterioration in the market environment that may affect the value of collateral (e.g., decline in real estate prices);

•significant deterioration in economic conditions; and

•disruption in the business model resulting from changes in technology or new entrants to the industry.

If deemed appropriate and necessary, a discounted cash flow analysis is performed to confirm whether a credit loss exists and, if so, the amount of the credit loss. We use the single best estimate approach for available-for-sale debt securities and consider all reasonably available data points, including industry analyses, credit ratings, expected defaults and the remaining payment terms of the debt security. For fixed rate available-for-sale debt securities, cash flows are discounted at the security's effective interest rate implicit in the security at the date of acquisition. If the available-for-sale debt security’s contractual interest rate varies based on subsequent changes in an independent factor, such as an index or rate, for example, the prime rate, the LIBOR, or the U.S. Treasury bill weekly average, that security’s effective interest rate is calculated based on the factor as it changes over the life of the security. If we intend to sell a debt security or believe we will more likely than not be required to sell a debt security before the amortized cost basis is recovered, any existing allowance will be written off against the security's amortized cost basis, with any remaining difference between the debt security's amortized cost basis and fair value recognized as an impairment loss in earnings.

Exclusive of securities where there is an intent to sell or where it is not more likely than not that the security will be required to be sold before recovery of its amortized cost basis, impairment for debt securities is separated into a credit component and a non-credit component. The credit component of an impairment is the difference between the security’s amortized cost basis and the present value of its expected future cash flows, while the non-credit component is the remaining difference between the security’s fair value and the present value of expected future cash flows. An allowance for expected credit losses will be recorded for the expected credit losses through income and the non-credit component is recognized in OCI. The amount of impairment recognized is limited to the excess of the amortized cost over the fair value of the available-for-sale debt security.

Pension

As a result of our NORCAL acquisition, we sponsor a frozen qualified defined benefit pension plan which covers substantially all NORCAL employees (except those that were previous employees of Medicus Insurance Company and FD Insurance Company, employees of PPM RRG as well as new hires after December 31, 2013). Accounting for pension benefits requires the use of assumptions for the valuation of the PBO and the expected performance of the plan assets.

We use December 31 as the measurement date for calculating our obligation related to this defined benefit pension plan and for estimating net periodic benefit cost (income) for the subsequent year. The PBO for pension benefits represents the present value of all future benefits earned as of the measurement date for vested and non-vested employees. At each measurement date, we review the various assumptions impacting the amounts recorded for the pension plan including the discount rates, which impacts the recorded value of the PBO and interest costs, and the expected return on plan assets.

To estimate the discount rate at the measurement date, we use a bond yield curve model, developed based on pricing and yield information for high quality corporate bonds. The assumption for the expected return on plan assets is based on the anticipated returns that will be earned by the portfolio over the long-term. The expected return on plan assets is influenced, but not determined, by historical portfolio performance. We assumed a 4.0% expected return on plan assets on our pension plan assets for the year ended December 31, 2022. For 2023, we increased our expected return on plan assets assumption to 5.3% based on our long-term outlook for the capital markets.

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The following table summarizes the estimated changes in our projected benefit obligation and net periodic benefit cost (income) for a hypothetical change in our discount rate and expected return on plan assets:

Shift in Basis Points
December 31, 2022
($ in millions)(100)Current100
Change in Discount Rate:
Benefit Obligation$83.8$74.2$66.3
Net periodic benefit cost (income)$0.3$0.1$0.4
Change in Expected Return on Plan Assets:
Net periodic benefit cost (income)$0.8$0.1$(0.6)

Accounting standards provide for the delayed recognition of differences between actual results and expected or estimated results. This delayed recognition of the differences is amortized into earnings over time. The differences between actual results and expected or estimated results are recognized in full in AOCI. Amounts recognized in AOCI are reclassified to earnings in a systematic manner over the average future service period of participants. During 2023, we expect to recognize nominal net pension expense and we do not expect that contributions to the pension plan will be required during 2023 nor do we anticipate making any discretionary contributions.

Deferred Taxes

Deferred federal income taxes arise from the recognition of temporary differences between the basis of assets and liabilities determined for financial reporting purposes and the basis determined for income tax purposes. Our temporary differences principally relate to our loss reserves, unearned and advanced premiums, DPAC, NOL and tax credit carryforwards, compensation related items, unrealized investment gains (losses) and basis differences on fixed assets, intangible assets and operating leases. Deferred tax assets and liabilities are measured using the enacted tax rates expected to be in effect when such benefits are realized. We review our deferred tax assets quarterly for impairment. If we determine that it is more likely than not that some or all of a deferred tax asset will not be realized, a valuation allowance is recorded to reduce the carrying value of the asset. In assessing the need for a valuation allowance, management is required to make certain judgments and assumptions about our future operations based on historical experience and information as of the measurement period regarding reversal of existing temporary differences, carryback capacity, future taxable income of the appropriate character (including its capital and operating characteristics) and tax planning strategies.

A significant portion of our deferred tax asset is related to unrealized losses on our fixed maturities due to the significant rise in interest rates in 2022. Any loss realized prior to recovery would require sufficient income of the appropriate character (i.e., capital gains), and in the appropriate timeframe, to realize the tax benefit. We believe that we have the intent and ability to hold these securities until their recovery. Our projected positive operating income, including the investment income generated from holding our debt securities until maturity, support our ability to implement this tax planning strategy.

A valuation allowance has been established against the deferred tax asset related to the NOL carryforwards for our U.K. operations and against a portion of the deferred tax asset related to a portion of our U.S. state NOL carryforwards. In addition, a valuation allowance was established in 2021 against the net deferred tax asset of ProAssurance American Mutual, a Risk Retention Group. As a taxpayer separate from the consolidated group, this entity has experienced cumulative losses in recent years. Management concluded that it was more likely than not that these deferred tax assets will not be realized. We also established a valuation allowance in a prior year against the deferred tax assets of certain SPCs at our wholly owned Cayman Islands reinsurance subsidiary, Inova Re. Due to the cumulative losses incurred in recent years by these SPCs, management concluded that a valuation allowance was required. As of December 31, 2022, management concluded that the previously recorded valuation allowances were still required against the deferred tax assets related to the NOL carryforwards for our U.K. entities, against the deferred tax assets related to our U.S. state NOL carryforwards and against the deferred tax assets of certain SPCs at Inova Re. Management’s assessment of the need for these valuation allowances at December 31, 2022 included an analysis of the available sources of income. See further discussion on ProAssurance’s deferred tax assets in Note 6 of the Notes to Consolidated Financial Statements.

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U.S. Tax Legislation

Coronavirus Aid, Relief and Economic Security Act

In response to COVID-19, the CARES Act was signed into law on March 27, 2020 and contains several provisions for corporations and eased certain deduction limitations originally imposed by the TCJA. See further discussion in Note 6 of the Notes to Consolidated Financial Statements. Temporary changes regarding NOL carryback provisions included in the CARES Act had a favorable impact on our liquidity, as we were able to carryback our 2019 and 2020 net operating losses to claim refunds (see discussion that follows in the Liquidity and Capital Resources and Financial Condition section under the heading "Taxes"). See further discussion in Note 6 of the Notes to Consolidated Financial Statements.

Unrecognized Tax Benefits

We evaluate tax positions taken on tax returns and recognize positions in our financial statements when it is more likely than not that we will sustain the position upon resolution with a taxing authority. If recognized, the benefit is measured as the largest amount of benefit that has a greater than 50% probability of being realized. We review uncertain tax positions each quarter, considering changes in facts and circumstances, such as changes in tax law, interactions with taxing authorities and developments in case law, and make adjustments as we consider necessary. Adjustments to our unrecognized tax benefits may affect our income tax expense, and settlement of uncertain tax positions may require the use of cash. Other than differences related to timing, no significant adjustments were considered necessary during 2022 or 2021. At December 31, 2022, our liability for unrecognized tax benefits approximated $3.6 million.

Goodwill / Intangibles

Goodwill and intangible assets are tested for impairment annually or more frequently if circumstances indicate an impairment may have occurred. The date of our annual impairment testing is October 1. Impairment of goodwill is tested at the reporting unit level, which is consistent with our reportable segments identified in Note 16 of the Notes to Consolidated Financial Statements.

When testing goodwill for impairment on our annual test date, we have the option to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more likely than not that the estimated fair value of a reporting unit is less than its carrying amount. If we elect to perform a qualitative assessment and determine that an impairment is more likely than not, we are then required to perform a quantitative impairment test; otherwise, no further analysis is required. We also may elect not to perform the qualitative assessment and, instead, proceed directly to the quantitative impairment test.

Performance of the qualitative goodwill impairment assessment requires judgment in identifying and considering the significance of relevant key factors, events and circumstances that affect the fair values of our reporting units. This requires consideration and assessment of external factors such as macroeconomic, industry, and market conditions, as well as entity-specific factors, such as our actual and planned financial performance. We also give consideration to the difference between each reporting unit's fair value and carrying value as of the most recent date that a fair value measurement was performed. If the results of the qualitative assessment conclude that it is not more likely than not that the fair value of a reporting unit exceeds its carrying value, additional quantitative impairment testing is performed.

The quantitative goodwill impairment test involves comparing the fair value of a reporting unit with its carrying value including goodwill. If the fair value of a reporting unit exceeds its carrying value, the reporting unit's goodwill is considered not to be impaired. However, if the carrying value of a reporting unit exceeds its fair value, an impairment loss is recorded in an amount equal to that excess. Any impairment charge recognized is limited to the amount of the respective reporting unit's allocated goodwill.

Determining the fair value of a reporting unit under the quantitative goodwill impairment test requires judgment and often involves the use of significant estimates and assumptions, including an assessment of external factors such as macroeconomic, industry and market conditions, as well as entity-specific factors, such as actual and planned financial performance. These estimates and assumptions could have a significant impact on whether or not an impairment charge is recognized and the magnitude of any such charge. To assist management in the process of determining any potential goodwill impairment, we may review and consider appraisals from accredited independent valuation firms. Estimates of fair value are primarily determined using discounted cash flows and market comparisons. These approaches involve significant estimates and assumptions, including projected future cash flows (including timing), discount rates reflecting the risks inherent in those future cash flows, perpetual growth rates, and selection of appropriate market comparable metrics and transactions.

For the most recent goodwill impairment test performed on October 1, 2022, management elected to bypass the optional qualitative impairment test and proceed directly to the quantitative impairment test for both the Workers’ Compensation Insurance and Segregated Portfolio Cell Reinsurance reporting units . In applying the quantitative approach, management estimated the fair value of the Workers' Compensation Insurance and Segregated Portfolio Cell Reinsurance reporting units

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using both an income approach and market approach based on the aforementioned valuation methodologies and process for developing assumptions. To corroborate the reporting units’ valuation, a reconciliation of the estimate of the aggregate fair value of the reporting units to ProAssurance's market capitalization was performed, including consideration of a control premium. As a result of the quantitative assessments, management concluded that the fair value of each of the Workers Compensation Insurance and Segregated Portfolio Cell Reinsurance reporting units exceeded the carrying value as of the testing date; therefore, goodwill was not impaired and no further goodwill impairment testing was required. No goodwill impairment was recorded during the year ended December 31, 2022. Furthermore, the analysis of our definite and indefinite lived intangible assets indicated no impairment at December 31, 2022. Additional information regarding our goodwill and intangible assets is included in Note 1 and Note 7 of the Notes to Consolidated Financial Statements.

Accounting Changes

Beginning in 2022, we revised our process for estimating ULAE as a result of substantially integrating NORCAL into our Specialty P&C segment operations. ULAE are costs that cannot be attributed to processing a specific claim and are allocated to net losses and loss adjustment expenses on the Consolidated Statement of Income and Comprehensive Income. We have accounted for this change prospectively as a change in accounting estimate. Changes in accounting estimate are reflected prospectively beginning in the period the change in estimate occurs. The change in our estimate of ULAE resulted in an increase to underwriting, policy acquisition and operating expenses with an offsetting decrease to net losses and loss adjustment expenses in our Specialty P&C segment; there was no impact on total expenses or net income (loss) in our Consolidated Statement of Income and Comprehensive Income for the year ended December 31, 2022. See further discussion on this change in estimate in the Segment Results - Specialty Property & Casualty section that follows and in Note 1 of the Notes to Consolidated Financial Statements.

We did not have any other change in accounting estimate or policy that had a material effect on our results of operations or financial position during 2022. We are not aware of any accounting changes not yet adopted as of December 31, 2022 that could have a material impact on our results of operations, financial position or cash flows. Note 1 of the Notes to Consolidated Financial Statements provides additional detail regarding accounting changes not yet adopted.

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Liquidity and Capital Resources and Financial Condition

Overview

ProAssurance Corporation is a holding company and is a legal entity separate and distinct from its subsidiaries. As a holding company, our principal source of external revenue is our investment revenues. In addition, dividends from our operating subsidiaries represent another source of funds for our obligations, including debt service and shareholder dividends. We also charge our operating subsidiaries within our Specialty P&C (including the acquired wholly owned operating subsidiaries of NORCAL effective January 1, 2022) and Workers' Compensation Insurance segments a management fee based on the extent to which services are provided to the subsidiary and the amount of gross premium written by the subsidiary. At December 31, 2022, we held cash and liquid investments of approximately $83 million outside our insurance subsidiaries that were available for use without regulatory approval or other restriction. We also have $250 million in permitted borrowings available under our Revolving Credit Agreement as well as the possibility of a $50 million accordion feature, if successfully subscribed. As of February 22, 2023, no borrowings were outstanding under our Revolving Credit Agreement.

During 2022, our operating subsidiaries paid dividends to us of approximately $51 million. In the aggregate, our insurance subsidiaries are permitted to pay dividends of approximately $133 million over the course of 2023 without prior approval of state insurance regulators. However, the payment of any dividend requires prior notice to the insurance regulator in the state of domicile, and the regulator may reduce or prevent the dividend if, in its judgment, payment of the dividend would have an adverse effect on the surplus of the insurance subsidiary. We make the decision to pay dividends from an insurance subsidiary based on the capital needs of that subsidiary and may pay less than the permitted dividend or may also request permission to pay an additional amount (an extraordinary dividend).

Cash Flows

Cash flows between periods compare as follows:

Year Ended December 31
(In thousands)20222021Change
Net cash provided (used) by:
Operating activities$(29,841)$73,970$(103,811)
Investing activities(61,997)(85,526)23,529
Financing activities(21,805)(60,624)38,819
Increase (decrease) in cash and cash equivalents$(113,643)$(72,180)$(41,463)

The principal components of our operating cash flows are the excess of premiums collected and net investment income over losses paid and operating costs, including income taxes. Timing delays exist between the collection of premiums and the payment of losses associated with the premiums. Premiums are generally collected within the twelve-month period after the policy is written, while our claim payments are generally paid over a more extended period of time. Likewise, timing delays exist between the payment of claims and the collection of any associated reinsurance recoveries.

The decrease in operating cash flows of $103.8 million in 2022 as compared to 2021 was primarily due to:

•An increase in paid losses of $280.2 million driven by our Specialty P&C segment primarily due to NORCAL paid losses and the payment of three large claims totaling $16.4 million during the first quarter of 2022.

•An increase in cash paid for operating expenses of $131.5 million driven by our Specialty P&C and Corporate segments, partially offset by lower transaction-related costs associated with our acquisition of NORCAL as compared to the prior year period. The increase in cash paid for operating expenses in our Specialty P&C and Corporate segments was driven by an increase in compensation-related costs primarily attributable to an increase in headcount due to the addition of NORCAL employees. Furthermore, the increase in our Specialty P&C segment reflected an increase in commissions paid driven by additional premiums from our acquisition of NORCAL and one-time expenses of $3.9 million in 2022. One-time expenses in 2022 were mainly comprised of one-time bonuses, employee severance charges and lease exit costs. Additionally, the increase reflected the termination of deferred compensation arrangements assumed in the NORCAL acquisition during the first quarter of 2022 totaling approximately $13.2 million. See further discussion of NORCAL's deferred compensation arrangements in Note 3 to the Notes to Consolidated Financial Statements.

•The effect of a tax refund of approximately $9.0 million which we received in February 2021 and an income tax extension payment of $1.1 million for the 2021 tax year during the second quarter of 2022. See additional discussion

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on this refund in our Liquidity section under the heading "Taxes" in Item 7 of our December 31, 2021 report on Form 10-K.

The decrease in operating cash flows was partially offset by:

•An increase in net premium receipts of $273.0 million primarily driven by our Specialty P&C segment, partially offset by a decrease in our Lloyd's Syndicates segment. The increase in our Specialty P&C segment was due to additional premiums from our acquisition of NORCAL and our focus on rate adequacy. The decrease in premium receipts in our Lloyd's Syndicates segment reflected our ceased participation in Syndicate 6131 for the 2022 underwriting year and the impact of our decreased participation in the results of Syndicates 1729 and 6131 for the 2021 underwriting year.

•An increase in cash received from investment income of $45.7 million driven by an increase in our investment balances due to the acquisition of NORCAL.

The remaining variance in operating cash flows in 2022 as compared to 2021 was composed of individually insignificant components.

We manage our investing cash flows to ensure that we will have sufficient liquidity to meet our obligations, taking into consideration the timing of cash flows from our investments, including interest payments, dividends and principal payments, as well as the expected cash flows to be generated by our operations as discussed in this section under the heading "Investing Activities and Related Cash Flows."

Our financing cash flows are primarily comprised of dividend payments. See further discussion of our financing activities in this section under the heading "Financing Activities and Related Cash Flows."

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Operating Activities and Related Cash Flows

Losses

The following table, known as the Analysis of Reserve Development, presents information over the preceding ten years regarding the payment of our losses as well as changes to (the development of) our estimates of losses during that time period. As noted in the table, we have completed various acquisitions over the ten year period which have affected original and re-estimated gross and net reserve balances as well as loss payments.

The table includes losses on both a direct and an assumed basis and is net of anticipated reinsurance recoverables. The gross liability for losses before reinsurance, as shown on the balance sheet, and the reconciliation of that gross liability to amounts net of reinsurance are reflected below the table. We do not discount our reserve for losses to present value. Information presented in the table is cumulative and, accordingly, each amount includes the effects of all changes in amounts for prior years. The table presents the development of our balance sheet reserve for losses; it does not present accident year or policy year development data. Conditions and trends that have affected the development of liabilities in the past may not necessarily occur in the future. Accordingly, it is not appropriate to extrapolate future redundancies or deficiencies based on this table.

The following may be helpful in understanding the Analysis of Reserve Development:

•The line entitled “Reserve for losses, undiscounted and net of reinsurance recoverables” reflects our reserve for losses and loss adjustment expense, less the receivables from reinsurers, each as reported in our Consolidated Balance Sheets at the end of each year (the Balance Sheet Reserves).

•The section entitled “Cumulative net paid, as of” reflects the cumulative amounts paid as of the end of each succeeding year with respect to the previously recorded Balance Sheet Reserves.

•The section entitled “Re-estimated net liability as of” reflects the re-estimated amount of the liability previously recorded as Balance Sheet Reserves that includes the cumulative amounts paid and an estimate of the remaining net liability based upon claims experience as of the end of each succeeding year (the Net Re-estimated Liability).

•The line entitled “Net cumulative redundancy (deficiency)” reflects the difference between the previously recorded Balance Sheet Reserve for each applicable year and the Net Re-estimated Liability relating thereto as of the end of the most recent fiscal year.

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Analysis of Reserve Development
December 31
(In thousands)20122013201420152016201720182019202020212022
Reserve for losses, undiscounted and net of reinsurance recoverables$1,860,076$1,825,304$1,812,299$1,730,308$1,681,423$1,659,971$1,709,129$1,878,140$1,945,099$3,059,328$2,973,196
Cumulative net paid, as of:
One Year Later311,835343,197380,508370,973354,526387,389428,940466,904454,902756,601
Two Years Later563,805571,690640,655616,016621,783668,340734,638790,989813,768
Three Years Later704,795732,892798,636799,689800,331857,177952,3091,046,573
Four Years Later800,189826,384910,998898,844930,769990,0231,133,462
Five Years Later852,873891,615964,897974,1041,004,9511,085,267
Six Years Later893,529924,3341,006,2151,018,1481,061,488
Seven Years Later915,730952,1181,030,7821,051,495
Eight Years Later930,375967,9451,045,980
Nine Years Later941,468976,074
Ten Years Later946,993
Re-estimated net liability as of:
End of Year1,860,0761,825,3041,812,2991,730,3081,681,4231,659,9711,709,1291,878,1401,945,0993,059,328
One Year Later1,644,2031,644,5161,651,1171,587,0291,547,8761,565,8671,696,8931,827,1531,902,8133,015,241
Two Years Later1,472,2591,483,3781,511,5421,460,6601,444,6191,487,9051,656,6151,805,4331,885,456
Three Years Later1,331,8281,358,5601,388,6821,356,0751,337,5711,446,5711,647,2831,792,202
Four Years Later1,231,3371,252,6051,288,5641,257,6501,306,2741,432,4771,632,836
Five Years Later1,157,4931,173,9751,221,4631,231,7131,299,0321,415,077
Six Years Later1,108,7161,126,3081,204,6421,230,5621,287,731
Seven Years Later1,078,0571,121,0871,199,6541,217,713
Eight Years Later1,075,2771,119,9841,183,973
Nine Years Later1,070,1611,110,216
Ten Years Later1,064,057
Net cumulative redundancy (deficiency)$796,019$715,088$628,326$512,595$393,692$244,894$76,293$85,938$59,643$44,087
Original gross liability - end of year$2,051,428$2,072,822$2,052,768$1,990,266$1,961,436$1,971,303$2,037,274$2,243,133$2,295,279$3,469,417
Reinsurance recoverables(191,352)(247,518)(240,469)(259,958)(280,013)(311,332)(328,145)(364,993)(350,180)(410,089)
Original net liability - end of year$1,860,076$1,825,304$1,812,299$1,730,308$1,681,423$1,659,971$1,709,129$1,878,140$1,945,099$3,059,328
Gross re-estimated liability - latest$1,186,101$1,252,152$1,344,636$1,422,764$1,522,082$1,672,741$1,914,194$2,098,742$2,197,211$3,425,358
Re-estimated reinsurance recoverables(122,044)(141,936)(160,663)(205,051)(234,351)(257,664)(281,358)(306,540)(311,755)(410,117)
Net re-estimated liability - latest$1,064,057$1,110,216$1,183,973$1,217,713$1,287,731$1,415,077$1,632,836$1,792,202$1,885,456$3,015,241
Gross cumulative redundancy (deficiency)$865,327$820,670$708,132$567,502$439,354$298,562$123,080$144,391$98,068$44,059

See table notes on following page.

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Table Notes

•We have elected to present reserve history for acquired entities on a prospective basis in the table above; therefore, certain items will not agree to the following table which details activity in our net reserve for losses.

•Given the Lloyd's Syndicates segment reserve is relatively small on a standalone basis as compared to our consolidated reserve, we have elected to exclude the segment's reserve history for all periods presented in the table above; therefore, certain items will not agree to the following table which details activity in our net reserve for losses.

•Reserves for 2012 and thereafter include gross and net reserves acquired in 2012 business combinations of $21.8 million and $19.2 million, respectively, which considers reductions of $3.6 million and $3.3 million, respectively, recorded in 2013 due to the re-estimation of the fair value of the acquired reserves.

•Reserves for 2013 include gross and net reserves acquired in 2013 business combinations of $201.1 million and $126.0 million, respectively.

•Reserves for 2014 include gross and net reserves acquired in 2014 business combinations of $153.2 million and $139.5 million, respectively.

•Reserves for 2021 include gross and net reserves acquired in 2021 business combinations of $1.2 billion and $1.1 billion, respectively.

In each year reflected in the table, we have estimated our reserve for losses utilizing the management and actuarial processes discussed under the heading "Reserve for Losses and Loss Adjustment Expenses" in the Critical Accounting Estimates section. Factors that have contributed to the variation in loss development are primarily related to the extended period of time required to resolve professional liability claims and include the following:

•The HCPL legal environment deteriorated in the late 1990’s and severity began to increase at a greater pace than anticipated in our rates and reserve estimates. We addressed the adverse severity trends through increased rates, stricter underwriting and modifications to claims handling procedures, and reflected this adverse severity trend when we established our initial reserves for subsequent years.

•These adverse severity trends later moderated, with that moderation becoming more pronounced beginning in 2009. We were cautious in giving full recognition to indications that the pace of severity increase had slowed, however we gave measured recognition of the improved trend in our reserve estimates. The favorable development was most pronounced for years 2004 to 2008, as the initial reserves for these accident years were established prior to substantial indication that severity trends were moderating. We gave stronger recognition to the lower severity trend as time elapsed and a greater percentage of claims were closed.

•A general decline in claims frequency has also been a contributor to favorable loss development. A significant portion of our policies through 2003 were issued on an occurrence basis, and a smaller portion of our ongoing business results from the issuance of extended reporting endorsements which have occurrence-like exposure. As claims frequency declined, the number of reported claims related to these coverages was less than originally expected.

•Beginning in 2017, we identified potential higher severity trends in the broader HCPL industry. These trends were also reflected in increases in estimates of ultimate losses for open HCPL claims for earlier accident years, which resulted in a lower amount of favorable development recognized in 2018 and 2017 as compared to prior years.

•During 2019 the loss experience in our Specialty line of business in our Specialty P&C segment deteriorated further, particularly in regard to the reserves we established for a large national healthcare account that experienced losses far exceeding the assumptions we made when underwriting the account, beginning in 2016. As a result, we strengthened our Specialty reserves through the recognition of net unfavorable development on prior accident years and a higher current accident year net loss ratio in our Specialty P&C segment in 2019.

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Activity in our net reserve for losses during 2022, 2021 and 2020 is summarized below:

Year Ended December 31
(In thousands)202220212020
Balance, beginning of year$3,579,940$2,417,179$2,346,526
Less reinsurance recoverables on unpaid losses and loss adjustment expenses451,741385,087390,708
Net balance, beginning of year3,128,1992,032,0921,955,818
Net reserves acquired from acquisitions1,089,103
Net losses:
Current year(1)(2)813,515797,732711,846
Favorable development of reserves established in prior years, net(2)(36,753)(45,483)(50,399)
Total776,762752,249661,447
Paid related to:
Current year(108,139)(109,925)(83,204)
Prior years(757,564)(635,320)(501,969)
Total paid(865,703)(745,245)(585,173)
Net balance, end of year3,039,2583,128,1992,032,092
Plus reinsurance recoverables on unpaid losses and loss adjustment expenses431,889451,741385,087
Balance, end of year$3,471,147$3,579,940$2,417,179

(1) During 2020, the aforementioned large national healthcare account did not renew on terms offered by the Company and exercised its contractual option to purchase extended reporting endorsement or "tail" coverage. As a result, we recognized total current year losses of $60.0 million (assumes a full limit loss) within the Specialty P&C segment for the year ended December 31, 2020.

(2) Current year net losses and prior accident year development for the years ended December 31, 2022 and 2021 includes certain purchase accounting adjustments associated with our acquisition of NORCAL. See Note 8 of the Notes to Consolidated Financial Statements for additional information.

At December 31, 2022 our gross reserve for losses included case reserves of approximately $2.3 billion and IBNR reserves of approximately $1.2 billion. Our consolidated gross reserve for losses on a GAAP basis exceeds the combined gross reserves of our insurance subsidiaries on a statutory basis by approximately $0.2 billion, which is principally due to the portion of the GAAP reserve for losses that is reflected for statutory accounting purposes as unearned premiums. These unearned premiums are applicable to extended reporting endorsements (“tail” coverage) issued without a premium charge upon death, disability or retirement of an insured who meets certain qualifications.

Reinsurance

Within our Specialty P&C segment, we use insurance and reinsurance (collectively, “reinsurance”) to provide capacity to write larger limits of liability, to provide reimbursement for losses incurred under the higher limit coverages we offer and to provide protection against losses in excess of policy limits. Within our Workers' Compensation Insurance segment, we use reinsurance to reduce our net liability on individual risks, to mitigate the effect of significant loss occurrences (including catastrophic events), to stabilize underwriting results and to increase underwriting capacity by decreasing leverage. In both our Specialty P&C and Workers' Compensation Insurance segments, we use reinsurance in risk sharing arrangements to align our objectives with those of our strategic business partners and to provide custom insurance solutions for large customer groups. Within our Lloyd's Syndicates segment, Syndicate 1729 utilizes reinsurance to provide capacity to write larger limits of liability on individual risks, to provide protection against catastrophic loss and to provide protection against losses in excess of policy limits. The purchase of reinsurance does not relieve us from the ultimate risk on our policies; however, it does provide reimbursement for certain losses we pay. We pay our reinsurers a premium in exchange for reinsurance of the risk. In certain of our excess of loss arrangements, the premium due to the reinsurer is determined by the loss experience of the business reinsured, subject to certain minimum and maximum amounts. Until all loss amounts are known, we estimate the premium due to the reinsurer. Changes to the estimate of premium owed under reinsurance agreements related to prior periods are recorded in the period in which the change in estimate occurs and can have a significant effect on net premiums earned.

We offer alternative market solutions whereby we cede certain premiums from our Workers' Compensation Insurance and Specialty P&C segments to either the SPCs at Inova Re or Eastern Re, our Cayman Islands reinsurance subsidiaries which are

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reported in our Segregated Portfolio Cell Reinsurance segment or captive insurers unaffiliated with ProAssurance for two programs. The majority of these policies are reinsured to the SPCs at Inova Re or Eastern Re, net of a ceding commission. See further discussion on our SPC operations in the Segment Results - Segregated Portfolio Cell Reinsurance section that follows. The alternative market workers' compensation policies are ceded from our Workers' Compensation Insurance segment to the SPCs under 100% quota share reinsurance agreements. The alternative market healthcare professional liability policies are ceded from our Specialty P&C segment to the SPCs under either excess of loss or quota share reinsurance agreements, depending on the structure of the individual program. The portion of the risk that is not ceded to an SPC is retained in our Specialty P&C segment and may also be reinsured under our standard healthcare professional liability reinsurance program, depending on the policy limits provided. The remaining premium written in our alternative market business is 100% ceded to unaffiliated captive insurers.

Excess of Loss Reinsurance Agreements

We generally reinsure risks under treaties (our excess of loss reinsurance agreements) pursuant to which the reinsurers agree to assume all or a portion of all risks that we insure above our individual risk retention levels, up to the maximum individual limits offered. Generally, these agreements are negotiated and renewed annually. Our HCPL and Medical Technology Liability treaties renew annually on October 1 and our Workers' Compensation treaty renews annually on May 1. Our HCPL and Medical Technology Liability treaties renewed October 1, 2022 at a slightly higher rate than the previous treaties; all other material terms were consistent with the expiring treaties. Our traditional workers' compensation treaty renewed May 1, 2022 at a higher rate than the previous treaty; all other material terms were consistent with the expiring treaty. The significant coverages provided by our current excess of loss reinsurance agreements are depicted in the following table.

Excess of Loss Reinsurance Agreements

Column 1Column 2Column 3Column 4Column 5Column 6
Healthcare Professional LiabilityMedical Technology & Life Sciences ProductsWorkers' Compensation - Traditional

(1) Effective October 1, 2020, one prepaid limit reinstatement of $21M and a second limit reinstatement of up to $21M for the second layer, subject to reinstatement premium, which attaches after the first reinstatement has been completely exhausted. All limit reinstatements thereafter require no additional premium. Effective October 1, 2021, limits can be reinstated a maximum of four times.

(2) Prior to October 1, 2020, retention was $1M.

(3) Historically, retention has ranged from 0% to 32.5%.

(4) Historically, retention has ranged from $1M to $2M.

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(5) Subject to a limit of $20M per individual claimant. If an individual loss were to exceed this level the Company would retain this excess exposure.

(6) Subject to an AAD where retention is 3.5% of subject earned premium in annual losses otherwise recoverable in excess of the $500K retention per loss occurrence.

Large HCPL risks that are above the limits of our basic reinsurance treaties may be reinsured on a facultative basis, whereby the reinsurer agrees to insure a particular risk up to a designated limit. We also have in place a number of risk sharing arrangements that apply to the first $1 million of losses for certain large healthcare systems and other insurance entities, as well as with certain insurance agencies that produce business for us.

Other Reinsurance Arrangements

For the workers' compensation business ceded to Inova Re and Eastern Re; each SPC has in place its own reinsurance arrangements; which are illustrated in the following table.

Segregated Portfolio Cell Reinsurance

Column 1Column 2Column 3
Per Occurrence CoverageAggregate Coverage

(1) The attachment point is based on a percentage of written premium within individual cells, ranges from 85% to 94%, and varies by cell.

Each SPC has participants and the profit or loss of each cell accrues fully to these cell participants. As previously discussed, we participate in certain SPCs to a varying degree. Each SPC maintains a loss fund initially equal to the difference between premium assumed by the cell and the ceding commission. The external participants of each cell provide collateral to us, typically in the form of a letter of credit that is initially equal to the difference between the loss fund of the SPC (amount of funds available to pay losses after deduction of ceding commission) and the aggregate attachment point of the reinsurance. Over time, an SPC's retained profits are considered in the determination of the collateral amount required to be provided by the cell's external participants.

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The level of reinsurance that Syndicate 1729 purchases is dependent on a number of factors, including its underwriting risk appetite for catastrophic exposure, the specific risks inherent in each line or class of business written and the pricing, coverage and terms and conditions available from the reinsurance market. Reinsurance protection by line of business is as follows:

•Reinsurance is utilized on a per risk basis for the property insurance and casualty coverages in order to mitigate risk volatility.

•Catastrophic protection is utilized on both our property insurance and casualty coverages to protect against losses in excess of policy limits as well as natural catastrophes.

•Both quota share reinsurance and excess of loss reinsurance are utilized to manage the net loss exposure on our property reinsurance coverages.

•Property umbrella excess of loss reinsurance is utilized for peak catastrophe and frequency of catastrophe exposures.

Syndicate 1729 may still be exposed to losses that exceed the level of reinsurance purchased as well as to reinstatement premiums triggered by losses exceeding specified levels. Cash demands on Syndicate 1729 can vary significantly depending on the nature and intensity of a loss event. For significant reinsured catastrophe losses, the inability or unwillingness of the reinsurer to make timely payments under the terms of the reinsurance agreement could have an adverse effect on Syndicate 1729's liquidity.

Taxes

We are subject to the tax laws and regulations of the U.S., Cayman Islands and U.K. We file a consolidated U.S. Federal income tax return that includes the parent company and its U.S. subsidiaries, except for ProAssurance American Mutual, a Risk Retention Group. Our filing obligations include a requirement to make quarterly payments of estimated taxes to the IRS using the corporate tax rate effective for the tax year. During the second quarter of 2022, we made a nominal safe harbor quarterly estimated tax payment and also made an income tax extension payment of $1.1 million for the 2021 tax year; we did not make any payments during the year ended December 31, 2021, as we expected NOL carryforwards to offset any income taxes due.

As a result of the CARES Act that was signed into law on March 27, 2020 we were permitted to carryback NOLs generated in tax years 2019 and 2020 for up to five years. See further discussion in the Critical Accounting Estimates section under the heading "U.S. Tax Legislation" and Note 6 of the Notes to Consolidated Financial Statements. We generated an NOL of approximately $33.3 million from the 2020 tax year that was carried back to the 2015 tax year that resulted in a tax refund of approximately $11.7 million received in February 2023.

As a result of our acquisition of NORCAL, we recorded $46.8 million of net deferred tax assets reflecting the remeasurement of NORCAL's historical net deferred tax assets at the acquisition date of May 5, 2021. The net deferred tax assets acquired from NORCAL were subject to recalculation following application of all purchase accounting adjustments and our assessment of the realizability of NORCAL's deferred tax assets. As a result of the NORCAL acquisition, we have U.S. Federal NOL carryforwards, which were approximately $36.1 million as of December 31, 2022. These NOL carryforwards are subject to limitation by Internal Revenue Code Section 382 and will begin to expire in 2035.

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Investing Activities and Related Cash Flows

Our investments at December 31, 2022 and December 31, 2021 are comprised as follows:

December 31, 2022December 31, 2021
($ in thousands)Carrying Value% of Total InvestmentCarrying Value% of Total Investment
Fixed maturities, available for sale:
U.S. Treasury obligations$221,6085%$238,5075%
U.S. Government-sponsored enterprise obligations19,9341%20,2341%
State and municipal bonds439,45010%519,19611%
Corporate debt1,781,45241%1,898,55639%
Residential mortgage-backed securities389,5408%453,9419%
Commercial mortgage-backed securities203,7945%245,6245%
Other asset-backed securities416,6949%457,6649%
Total fixed maturities, available-for-sale3,472,47279%3,833,72279%
Fixed maturities, trading43,4341%43,6701%
Total fixed maturities3,515,90680%3,877,39280%
Equity investments(1)143,7383%214,8074%
Short-term investments245,3136%216,9874%
BOLI81,7462%81,7672%
Investment in unconsolidated subsidiaries305,2107%335,5767%
Other investments95,7702%101,7943%
Total investments$4,387,683100%$4,828,323100%
(1)Includes $112.1 million and $187.1 million of investment grade bond funds as of December 31, 2022 and 2021, respectively, which are not subject to significant equity price risk.

At December 31, 2022, 99% of our investments in available-for-sale fixed maturity securities were rated and the average rating was A+ . The distribution of our investments in available-for-sale fixed maturity securities by rating were as follows:

December 31, 2022December 31, 2021
($ in thousands)Carrying Value% of Total InvestmentCarrying Value% of Total Investment
Rating*
AAA$1,008,23029%$1,129,13629%
AA+113,6593%130,0773%
AA210,2476%254,5707%
AA-190,1065%194,6615%
A+264,9508%221,4736%
A432,44212%521,59814%
A-345,67110%364,1479%
BBB+213,7946%292,9848%
BBB305,9879%300,6508%
BBB-137,5964%127,9823%
Below investment grade249,4007%296,4448%
Not rated3901%%
Total$3,472,472100%$3,833,722100%
*Average of three NRSRO sources, presented as an S&P equivalent. Source: S&P, Copyright ©2023, S&P Global Market Intelligence

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A detailed listing of our investment holdings as of December 31, 2022 is located under the Financial Information heading on the Investor Relations page of our website which can be reached directly at https://investor.proassurance.com/financial-information/quarterly-investment-supplements/default.aspx or through links from the Investor Relations section of our website, investor.proassurance.com.

We manage our investments to ensure that we will have sufficient liquidity to meet our obligations, taking into consideration the timing of cash flows from our investments, including interest payments, dividends and principal payments, as well as the expected cash flows to be generated by our operations. In addition to the interest and dividends we will receive from our investments, we anticipate that between $90 million and $160 million of our portfolio will mature (or be paid down) each quarter over the next twelve months and become available, if needed, to meet our cash flow requirements. The primary outflow of cash at our insurance subsidiaries is related to paid losses and operating costs, including income taxes. The payment of individual claims cannot be predicted with certainty; therefore, we rely upon the history of paid claims in estimating the timing of future claims payments with consideration to current and anticipated industry trends and macroeconomic conditions. To the extent that we may have an unanticipated shortfall in cash, we may either liquidate securities or borrow funds under existing borrowing arrangements through our Revolving Credit Agreement and the FHLB system. Permitted borrowings under our Revolving Credit Agreement are $250 million with the possibility of an additional $50 million accordion feature, if successfully subscribed. Given the duration of our investments, we do not foresee a shortfall that would require us to meet operating cash needs through additional borrowings. Additional information regarding our Revolving Credit Agreement is detailed in Note 11 of the Notes to Consolidated Financial Statements.

At December 31, 2022, our FAL was comprised of fixed maturity securities with a fair value of $23.8 million and cash and cash equivalents of $1.0 million deposited with Lloyd's. See further discussion in Note 4 of the Notes to Consolidated Financial Statements. During the second quarter of 2022, we received a return of approximately $5.5 million of cash from our FAL balances given Syndicate 6131 ceased underwriting on a quota share basis with Syndicate 1729 beginning with the 2022 underwriting year as well as the settlement of our participation in the results of Syndicate 1729 and Syndicate 6131 for the 2019 underwriting year. Further, during the fourth quarter of 2022, we received a return of approximately $5.6 million of cash from our FAL balances due to lower capital requirements for the 2023 underwriting year following Lloyd's of London's review of the 2023 business plan.

Our investment portfolio continues to be primarily composed of high quality fixed income securities with approximately 92% of our fixed maturities being investment grade securities as determined by national rating agencies. The weighted average effective duration of our fixed maturity securities at December 31, 2022 was 3.50 years; the weighted average effective duration of our fixed maturity securities combined with our short-term securities was 3.27 years.

The carrying value and unfunded commitments for certain of our investments were as follows:

Carrying ValueDecember 31, 2022
($ in thousands, except expected funding period)December 31, 2022December 31, 2021Unfunded CommitmentExpected funding period in years
Qualified affordable housing project tax credit partnerships (1)$4,088$12,424$2534
All other investments, primarily investment fund LPs/LLCs301,122323,152120,0434
Total$305,210$335,576$120,296
(1) The carrying value reflects our total commitments (both funded and unfunded) to the partnerships, less any amortization, since our initial investment. We fund these investments based on funding schedules maintained by the partnerships.

Investment fund LPs/LLCs are by nature less liquid and may involve more risk than other investments. We manage our risk through diversification of asset class and geographic location. At December 31, 2022, we had investments in 35 separate investment funds with a total carrying value of $301.1 million which represented approximately 7% of our total investments. Our investment fund LPs/LLCs generate earnings from trading portfolios, secured debt, debt securities, multi-strategy funds and private equity investments, and the performance of these LPs/LLCs is affected by the volatility of equity and credit markets. For our investments in LPs/LLCs, we record our allocable portion of the partnership operating income or loss as the results of the LPs/LLCs become available, typically following the end of a reporting period.

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Financing Activities and Related Cash Flows

Treasury Shares

Treasury share activity for 2022, 2021 and 2020 was as follows:

(In thousands)202220212020
Treasury shares at the beginning of the period9,3259,3259,325
Shares reacquired, at cost of $3.3 million for 2022139
Treasury shares at the end of the period9,4649,3259,325

We did not repurchase any common shares subsequent to December 31, 2022 and as of February 22, 2023 our remaining Board authorization was approximately $106.4 million.

ProAssurance Shareholder Dividends

Our Board declared cash dividends during 2022, 2021 and 2020 as follows:

Quarterly Cash Dividends Declared, per Share
202220212020
First Quarter$0.05$0.05$0.31
Second Quarter$0.05$0.05$0.05
Third Quarter$0.05$0.05$0.05
Fourth Quarter$0.05$0.05$0.05

Each dividend was paid in the month following the quarter in which it was declared. Cash dividends totaling $11 million were paid during each of the years ended December 31, 2022 and 2021 and cash dividends totaling $39 million were paid during the year ended December 31, 2020. Any decision to pay future cash dividends is subject to the Board’s final determination after a comprehensive review of financial performance, future expectations and other factors deemed relevant by the Board.

Debt

At December 31, 2022, our debt included $250 million of outstanding unsecured senior notes. The notes bear interest at 5.3% annually and are due in November 2023, although they may be redeemed in whole or part prior to maturity. There are no financial covenants associated with these notes.

NORCAL Insurance Company, successor to NORCAL Mutual Insurance Company, issued Contribution Certificates, which bear interest at 3.0% annually and are due in 2031, to certain NORCAL policyholders in the conversion. The Contribution Certificates have a principal amount of $191 million and were recorded at their fair value of $175 million at the date of the NORCAL acquisition on May 5, 2021. The difference of $16 million between the recorded acquisition date fair value and the principal balance of the Contribution Certificates will be accreted utilizing the effective interest method over the term of the certificates of ten years as an increase to interest expense. Furthermore, interest payments are subject to deferral if we do not receive permission from the California Department of Insurance prior to payment. We received permission from the California Department of Insurance to pay the first annual interest payment which was paid in April 2022. See Note 2 and Note 11 of the Notes to Consolidated Financial Statements for additional information on the Contribution Certificates issued in the NORCAL acquisition. There are no financial covenants associated with these certificates.

We have a Revolving Credit Agreement, which expires in November 2024, that may be used for general corporate purposes, including, but not limited to, short-term working capital, share repurchases as authorized by the Board and support for other activities. Our Revolving Credit Agreement permits borrowings of up to $250 million as well as the possibility of a $50 million accordion feature, if successfully subscribed. At December 31, 2022, there were no outstanding borrowings on our Revolving Credit Agreement; we are in compliance with the financial covenants of the Revolving Credit Agreement.

Additional information regarding our debt is provided in Note 11 of the Notes to Consolidated Financial Statements.

We utilized an interest rate cap agreement with a notional amount of $35 million to manage our exposure to increases in LIBOR. Per the interest rate cap agreement, we were entitled to receive cash payments if and when the three-month LIBOR exceeds 2.35%. In April 2022, we terminated our interest rate cap agreement that was previously utilized to manage our exposure to increases in LIBOR on Mortgage Loans that were fully repaid in 2021. As a result of the termination, we received $2.1 million in proceeds during the second quarter of 2022.

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Three of our insurance subsidiaries are members of an FHLB. Through membership, those subsidiaries have access to secured cash advances which can be used for liquidity purposes or other operational needs. In order for us to use FHLB proceeds, regulatory approvals may be required depending on the nature of the transaction. To date, those subsidiaries have not materially utilized their membership for borrowing purposes.

Results of Operations - Year Ended December 31, 2022 Compared to Year Ended December 31, 2021

Selected consolidated financial data for each period is summarized in the table below.

Year Ended December 31
($ in thousands, except per share data)20222021Change
Revenues:
Net premiums written$1,014,137$882,721$131,416
Net premiums earned$1,029,581$971,668$57,913
Net investment result100,860119,496(18,636)
Net investment gains (losses)(33,157)24,310(57,467)
Other income9,4048,936468
Total revenues1,106,6881,124,410(17,722)
Expenses:
Net losses and loss adjustment expenses776,762752,24924,513
Underwriting, policy acquisition and operating expenses307,338268,24639,092
SPC U.S. federal income tax expense1,7591,947(188)
SPC dividend expense (income)6,67310,050(3,377)
Interest expense20,37219,719653
Total expenses1,112,9041,052,21160,693
Gain on bargain purchase74,408(74,408)
Income (loss) before income taxes(6,216)146,607(152,823)
Income tax expense (benefit)(5,814)2,483(8,297)
Net income (loss)$(402)$144,124$(144,526)
Non-GAAP operating income (loss)$24,509$75,892$(51,383)
Earnings (loss) per share:
Basic$(0.01)$2.67$(2.68)
Diluted$(0.01)$2.67$(2.68)
Non-GAAP operating income (loss) per share:
Basic$0.45$1.41$(0.96)
Diluted$0.45$1.40$(0.95)
Net loss ratio75.4%77.4%(2.0 pts)
Underwriting expense ratio29.9%27.6%2.3 pts
Combined ratio105.3%105.0%0.3 pts
Operating ratio96.0%97.7%(1.7 pts)
Effective tax rate93.5%1.7%91.8 pts
Return on equity*%5.3%(5.3 pts)
Non-GAAP operating return on equity*1.9%5.6%(3.7 pts)
*See further discussion on this calculation in the Executive Summary of Operations section under the heading "Non-GAAP Operating ROE."
In all tables that follow, the abbreviation "nm" indicates that the information or the percentage change is not meaningful.

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Executive Summary of Operations

The following sections provide an overview of our consolidated and segment results of operations for the year ended December 31, 2022 as compared to the year ended December 31, 2021. See the Segment Results sections that follow for additional information regarding each segment's results. For a full discussion of the changes in the financial condition, results of operations and cash flows for the year ended December 31, 2021 as compared to the year ended December 31, 2020, please refer to Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" section of ProAssurance's December 31, 2021 report on Form 10-K.

Revenues

The following table shows our consolidated and segment net premiums earned:

Year Ended December 31
($ in thousands)20222021Change
Net premiums earned
Specialty P&C$769,773$695,008$74,76510.8%
Workers' Compensation Insurance166,371164,6001,7711.1%
Segregated Portfolio Cell Reinsurance69,81063,6886,1229.6%
Lloyd's Syndicates23,62748,372(24,745)(51.2%)
Consolidated total$1,029,581$971,668$57,9136.0%

For the year ended December 31, 2022, consolidated net premiums earned included earned premium from our acquisition of NORCAL of $289.0 million as compared to $214.6 million in 2021. Excluding NORCAL premiums, our consolidated net premiums earned decreased $16.5 million in 2022 as compared to 2021.

•The decrease in our Lloyd's Syndicates segment for the year ended December 31, 2022 was due to our decreased participation in the results of Syndicate 1729 and Syndicate 6131 for the 2021 underwriting year and, to a lesser extent, our ceased participation in Syndicate 6131 for the 2022 underwriting year.

•Net premiums earned in our Segregated Portfolio Cell Reinsurance segment increased during 2022 driven by tail coverage premiums primarily related to one program in which we do not participate, which resulted in $4.9 million of one-time premium written and fully earned as well as an increase in audit premium billed to policyholders in 2022.

•For our Workers' Compensation Insurance segment, net premiums earned increased for 2022 due to an increase in audit premiums billed to policyholders in 2022 as well as the change in the carried EBUB estimate, which increased $1.5 million in 2022 as compared to a reduction of $1.2 million in 2021, partially offset by the competitive workers' compensation market conditions.

•Net premiums earned in our Specialty P&C segment, excluding NORCAL premiums, remained relatively unchanged during 2022 as compared to 2021.

The following table shows our consolidated net investment result:

Year Ended December 31
($ in thousands)20222021Change
Net investment income$95,972$70,522$25,45036.1%
Equity in earnings (loss) of unconsolidated subsidiaries*4,88848,974(44,086)(90.0%)
Net investment result$100,860$119,496$(18,636)(15.6%)
*Equity in earnings (loss) of unconsolidated subsidiaries includes our share of the operating results of interests we hold in certain LPs/LLCs as well as operating losses associated with our tax credit partnership investments, which are designed to generate returns in the form of tax credits and tax-deductible project operating losses.

The increase in our consolidated net investment income for the year ended December 31, 2022 as compared to 2021 reflected higher average book yields as we continue to reinvest at higher rates as our portfolio matures and the addition of NORCAL's investment portfolio. Furthermore, the increase in net investment income during 2022 reflected the prior year impact of capital planning in anticipation of closing the NORCAL acquisition. Equity in earnings of unconsolidated subsidiaries decreased in 2022 primarily due to the performance of certain LP/LLCs, which are primarily reported to us on a one-quarter lag, and reflected lower market valuations during 2022, partially offset by lower amortization of tax credit partnership operating losses.

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The following table shows our total consolidated net investment gains (losses):

Year Ended December 31
($ in thousands)20222021Change
Net impairment losses recognized in earnings$(1,758)$$(1,758)nm
Other net investment gains (losses)(1)(31,399)24,310(55,709)(229.2%)
Net investment gains (losses)$(33,157)$24,310$(57,467)(236.4%)
(1) Consolidated other net investment gains (losses) in 2022 include a gain of $9.0 million recognized during the fourth quarter of 2022 reflecting the change in the fair value of contingent consideration issued in connection with the NORCAL acquisition (see Note 2 of the Notes to Consolidated Financial Statements). We do not consider this adjustment in assessing the financial performance of any of our operating or reportable segments and therefore, we have excluded it from the Segment Results sections that follow. See Note 16 of the Notes to Consolidated Financial Statements for a reconciliation of our segment results to our consolidated results.

We recognized $33.2 million of net investment losses for the year ended December 31, 2022 driven by unrealized holding losses resulting from changes in the fair value of our equity investments and convertible securities. We recognized $24.3 million of net investment gains for the year ended December 31, 2021, driven primarily by realized gains on the sale of certain available-for-sale fixed maturities and other investments, partially offset by unrealized holding losses resulting from decreases in the fair value on our equity portfolio.

Expenses

The following table shows our consolidated and segment net loss ratios and net prior accident year reserve development.

Year Ended December 31
($ in millions)20222021Change
Current accident year net loss ratio
Consolidated ratio79.0%82.1%(3.1pts)
Specialty P&C83.1%87.5%(4.4pts)
Workers' Compensation Insurance71.8%74.0%(2.2pts)
Segregated Portfolio Cell Reinsurance65.3%67.1%(1.8pts)
Lloyd's Syndicates37.2%51.9%(14.7pts)
Calendar year net loss ratio
Consolidated ratio75.4%77.4%(2.0pts)
Specialty P&C79.2%82.8%(3.6pts)
Workers' Compensation Insurance67.0%69.7%(2.7pts)
Segregated Portfolio Cell Reinsurance56.3%51.1%5.2pts
Lloyd's Syndicates68.3%61.6%6.7pts
Favorable (unfavorable) reserve development, prior accident years
Consolidated$36.8$45.5$(8.7)
Specialty P&C$29.8$32.9$(3.1)
Workers' Compensation Insurance$8.0$7.1$0.9
Segregated Portfolio Cell Reinsurance$6.3$10.2$(3.9)
Lloyd's Syndicates$(7.3)$(4.7)$(2.6)

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The primary drivers of the change in our consolidated current accident year net loss ratio for the year ended December 31, 2022 as compared to 2021 were as follows:

(In percentage points)Increase (Decrease) 2022 versus 2021
Estimated ratio increase (decrease) attributable to:
NORCAL Operations(1.4 pts)
NORCAL Acquisition - Purchase Accounting Adjustment0.2 pts
Change in Estimate of ULAE(2.5 pts)
All other, net0.6 pts
Decrease in the consolidated current accident year net loss ratio(3.1 pts)

•Excluding the impact of the items specifically identified in the table above, our consolidated current accident year net loss ratio increased 0.6 percentage points for the year ended December 31, 2022 driven by our Specialty P&C segment, partially offset by our Workers' Compensation Insurance, Segregated Portfolio Cell Reinsurance and Lloyd's Syndicates segments. As a result of actuarial analyses performed by both internal and consulting actuaries during 2022, we increased our current accident year net loss ratio in our Specialty P&C segment, excluding NORCAL, driven by an increase to certain expected loss ratios in our Standard Physician line of business due to higher than anticipated loss severity trends in select jurisdictions, which emerged primarily in the fourth quarter of 2022. See additional information in the Segment Results - Specialty Property and Casualty section that follows. In our Workers' Compensation Insurance segment, the lower current accident year net loss ratio for 2022 reflected an improvement in loss frequency and severity trends, partially offset by the continuation of intense price competition and the resulting renewal rate decreases. Further, the current accident year net loss ratio in our Workers' Compensation Insurance segment for 2021 reflects workers returning to full employment after the lifting of pandemic-related restrictions and the labor shortage. In our Segregated Portfolio Cell Reinsurance segment, the improvement in the current accident year net loss ratio for 2022 primarily reflects favorable trends in prior accident year workers' compensation claim results and their impact on our analysis of the current year loss estimate. For our Lloyd's Syndicates segment, the lower current accident year net loss ratio was driven by decreases to certain loss estimates during the first quarter of 2022, partially offset by lower reinsurance recoveries as a proportion of gross losses as compared to the prior year period.

•Initial expected loss ratios associated with NORCAL policies are higher than the average for the other books of business in our Specialty P&C segment; however, we reduced certain expected NORCAL loss ratios during the fourth quarter of 2021 and also in the third and fourth quarters of 2022 due to favorable frequency trends some of which, we believe, are primarily attributable to our re-underwriting efforts, leading to a 1.4 percentage point improvement in our consolidated current accident year net loss ratio in 2022. We completed the process of evaluating the NORCAL book of business and implementing ProAssurance's underwriting strategies during the second quarter of 2022. Furthermore, the 1.4 percentage point improvement also reflected a reduction to our reserve related to NORCAL's DDR coverage endorsements in the fourth quarter of 2022.

•Also as a result of our acquisition of NORCAL, our consolidated current accident year net loss ratio in 2022 and 2021 was impacted by the purchase accounting amortization of the negative VOBA associated with NORCAL's assumed unearned premium of $4.9 million and $6.7 million, respectively, which was recorded as a reduction to current accident year net losses. As of June 30, 2022, the negative VOBA was fully amortized which resulted in a 0.2 percentage point increase in 2022.

•Beginning in 2022, we revised our process of estimating ULAE in our Specialty P&C segment as a result of substantially integrating NORCAL into our operations, which accounted for a 2.5 percentage point decrease in our consolidated current accident year net loss ratio for the year ended December 31, 2022 with an offsetting 2.5 percentage point increase in our consolidated expense ratio for the same current period with no impact to our consolidated combined ratio, total expenses or net income (loss). See additional information on this change in ULAE estimate in the Segment Results - Specialty Property and Casualty section that follows.

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In both 2022 and 2021, our consolidated calendar year net loss ratio was lower than our consolidated current accident year net loss ratio due to the recognition of net favorable prior year reserve development, as shown in the previous table. The following table shows the components of our consolidated net prior accident year reserve development:

Year Ended December 31
($ in thousands)20222021Change
Net favorable reserve development$25,934$37,576$(11,642)(31.0%)
NORCAL Acquisition - Purchase Accounting Amortization*10,8197,9072,91236.8%
Total net favorable reserve development$36,753$45,483$(8,730)(19.2%)
*See Note 2 of the Notes to Consolidated Financial Statements for additional information on the purchase accounting adjustments.

•Development recognized in our Specialty P&C segment during 2022 principally related to accident years 2017 and 2020 through 2021. Net favorable prior accident year reserve development recognized in our Specialty P&C segment included favorable development related to NORCAL's 2021 accident year and, to a lesser extent, our Medical Technology Liability line of business. Net favorable prior accident year reserve development recognized in 2022 was partially offset by unfavorable reserve development in our HCPL line of business, excluding NORCAL, driven by higher than anticipated loss severity trends in select jurisdictions, which emerged primarily in the fourth quarter of 2022. We have not recognized any development related to NORCAL's accident years 2020 or prior since the date of acquisition on May 5, 2021.

•We reduced our prior accident year IBNR reserve for COVID-19 by $9.0 million and $1.0 million during 2022 and 2021, respectively, as early first notices of potential claims related to anticipated COVID losses have not turned into claims. As of December 31, 2022, we no longer carry a specific IBNR reserve for potential COVID-19 related losses. See additional discussion on the COVID-19 IBNR reserve in our Critical Accounting Estimates section under the heading "Reserve for Losses and Loss Adjustment Expenses."

•For our Workers' Compensation Insurance and Segregated Portfolio Cell Reinsurance segments, the net favorable development in 2022 reflected overall favorable trends in claim closing patterns.

•We recognized $7.3 million of unfavorable prior year development in our Lloyd's Syndicates segment during the year ended December 31, 2022 driven by higher than expected losses and development on certain large claims, primarily catastrophe related losses.

Our consolidated and segment underwriting expense ratios were as follows:

Year Ended December 31
20222021Change
Underwriting Expense Ratio
Consolidated (1)29.9%27.6%2.3pts
Specialty P&C25.0%18.4%6.6pts
Workers' Compensation Insurance32.9%31.8%1.1pts
Segregated Portfolio Cell Reinsurance29.1%34.0%(4.9pts)
Lloyd's Syndicates31.4%37.1%(5.7pts)
Corporate (2)3.4%2.7%0.7pts
(1) Consolidated underwriting expenses include transaction-related costs for 2022 and 2021 associated with our acquisition of NORCAL that are not included in a segment as we do not consider these costs in assessing the financial performance of any of our operating or reportable segments. See Note 16 of the Notes to Consolidated Financial Statements for a reconciliation of our segment results to our consolidated results.
(2) There are no net premiums earned associated with the Corporate segment. Ratios shown are the contribution of the Corporate segment to the consolidated ratio (Corporate operating expenses divided by consolidated net premiums earned).

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The change in our consolidated underwriting expense ratio for the year ended December 31, 2022 as compared to 2021 was primarily attributable to the following:

(In percentage points)Increase (Decrease) 2022 versus 2021
Estimated ratio increase (decrease) attributable to:
Change in Net Premiums Earned and DPAC amortization0.5 pts
NORCAL DPAC Amortization - Prior Period Purchase Accounting Impact1.4 pts
Change in Estimate of ULAE2.5 pts
Transaction-related Costs(1)(2.4 pts)
One-Time Expenses(2)0.4 pts
All other, net(0.1 pts)
Increase in the underwriting expense ratio2.3 pts
(1) Represents transaction-related costs associated with our acquisition of NORCAL of $1.9 million and $25.0 million for 2022 and 2021, respectively. While these costs are included in our consolidated results, they are not allocated to an individual segment as we do not consider these costs in assessing the financial performance of any or our operating of reportable segments. See Note 16 of the Notes to Consolidated Financial Statements for a reconciliation of our segment results to our consolidated results.
(2) Represents one-time expenses of $3.9 million for 2022 mainly comprised of one-time bonuses, accelerated depreciation associated with a decommissioned IT system, employee severance charges and lease exit costs in our Specialty P&C segment.

•Excluding the impact of items specifically identified in the table above, our consolidated underwriting expense ratio for 2022 remained relatively unchanged as compared to 2021.

•As shown in the previous table, our consolidated underwriting expense ratio for 2022 is higher as compared to 2021 reflecting the impact of lower DPAC amortization than would have otherwise been recognized during 2021 associated with NORCAL policies due to the application of GAAP purchase accounting rules. Under these purchase accounting rules, the capitalized policy acquisition costs for NORCAL policies written prior to the acquisition date were written off through purchase accounting on May 5, 2021 rather than being expensed pro rata over the remaining term of the associated policies (see Note 2 of the Notes to Consolidated Financial Statements in our December 31, 2021 report on Form 10-K for more information). DPAC amortization in our Specialty P&C segment for 2022 was approximately $1.0 million lower than would have otherwise been recognized. Normalizing the prior year amortization would have increased our consolidated underwriting expense ratio for 2021 by 1.4 percentage points.

•As shown in the previous table, the consolidated underwriting expense ratio for 2022 reflected a revision to our process of estimating ULAE in our Specialty P&C segment, as previously discussed, which resulted in approximately $25.4 million of expenses remaining in operating expenses instead of being allocated to net losses and loss adjustment expenses. As a result, this change in ULAE estimate accounted for a 2.5 percentage point increase in our consolidated underwriting expense ratio with an offsetting 2.5 percentage point decrease to our consolidated net loss ratio during the same period with no impact to our consolidated combined ratio, total expenses or net income (loss). See additional discussion on this change in ULAE estimate in the Segment Results - Specialty Property and Casualty section that follows.

Gain on Bargain Purchase

As a result of the NORCAL acquisition, we recognized a gain on bargain purchase of $74.4 million during the second quarter of 2021 representing the excess of the fair value of the identifiable assets acquired and liabilities assumed over the purchase consideration. We do not consider this gain in assessing the financial performance of any of our operating or reportable segments and therefore, we have excluded it from the Segment Results sections that follow. See further discussion around the gain on bargain purchase recognized from the NORCAL acquisition in Note 2 of the Notes to Consolidated Financial Statements.

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Taxes

Our consolidated effective tax rates for the years ended December 31, 2022 and 2021 were as follows:

($ in thousands)Year Ended December 31
20222021Change
Income (loss) before income taxes$(6,216)$146,607$(152,823)(104.2%)
Income tax expense (benefit)(5,814)2,483(8,297)(334.2%)
Net income (loss)$(402)$144,124$(144,526)(100.3%)
Effective tax rate93.5%1.7%91.8 pts

We recognized an income tax benefit in 2022 of $5.8 million and income tax expense of $2.5 million in 2021. Our effective tax rates for the years ended December 31, 2022 and 2021 were different from the statutory federal income tax rate of 21% typically due to the benefit recognized from the tax credits transferred to us from our tax credit partnership investments. Additionally, our effective tax rate for 2022 was impacted by a gain of $9.0 million related to the change in fair value of contingent consideration issued in connection with the NORCAL acquisition, all of which was non-taxable. For 2021, our effective tax rate was also affected by the non-taxable $74.4 million gain on bargain purchase related to the NORCAL acquisition. See further information on other notable items impacting our effective tax rate for the years ended December 31, 2022 and 2021 in the Segment Results - Corporate section that follows under the heading "Taxes."

Operating Ratio

Our operating ratio is our combined ratio, less our investment income ratio. This ratio provides the combined effect of underwriting profitability and investment income. Our operating ratio for the years ended December 31, 2022 and 2021 was as follows:

Year Ended December 31
20222021Change
Combined ratio105.3%105.0%0.3pts
Less: investment income ratio9.3%7.3%2.0pts
Operating ratio96.0%97.7%(1.7pts)
Combined ratio, excluding transaction-related costs*105.1%102.4%2.7pts
*Excludes transaction-related costs of $1.9 million and $25.0 million in 2022 and 2021, respectively, associated with our acquisition of NORCAL which are included in consolidated results and do not reflect normal operating expenses. See previous discussion under the heading "Expenses."

The primary drivers of the change in our operating ratio were as follows:

(In percentage points)Increase (Decrease) 2022 versus 2021
Estimated ratio increase (decrease) attributable to:
Investment Results(2.0 pts)
Transaction-related Costs(2.4 pts)
NORCAL DPAC Amortization - Prior Period Purchase Accounting Impact1.4 pts
All other, net1.3 pts
Decrease in the operating ratio(1.7 pts)

Excluding the impact of the items specifically identified in the table above, our operating ratio for 2022 increased as compared to 2021 driven by lower favorable prior year development, partially offset by an improvement in our Specialty P&C segment's current accident year net loss ratio. The improvement in our Specialty P&C segment's current accident year net loss ratio in 2022 was primarily attributable to a decrease to certain expected NORCAL loss ratios during the third and fourth quarters of 2022 due to favorable frequency trends, partially offset by an increase to certain expected loss ratios in our Standard Physician line of business due to higher than anticipated loss emergence in select jurisdictions. See previous discussion in this section under the heading "Expenses" and further discussion in our Segment Operating Results sections that follow.

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Non-GAAP Financial Measures

Non-GAAP Operating Income (Loss)

Non-GAAP operating income (loss) is a financial measure that is widely used to evaluate performance within the insurance sector. In calculating Non-GAAP operating income (loss), we have excluded the effects of the items listed in the following table that do not reflect normal results. We believe Non-GAAP operating income (loss) presents a useful view of the performance of our insurance operations, however it should be considered in conjunction with net income (loss) computed in accordance with GAAP.

The following table is a reconciliation of net income (loss) to Non-GAAP operating income (loss):

Year Ended December 31
(In thousands, except per share data)20222021
Net income (loss)$(402)$144,124
Items excluded in the calculation of Non-GAAP operating income (loss):
Net investment (gains) losses(1)33,157(24,310)
Net investment gains (losses) attributable to SPCs which no profit/loss is retained (2)(2,138)3,253
Transaction-related costs (3)1,86224,977
Guaranty fund assessments (recoupments)541228
Gain on bargain purchase (4)(74,408)
Pre-tax effect of exclusions33,422(70,260)
Tax effect, at 21% (5)(8,511)2,028
After-tax effect of exclusions24,911(68,232)
Non-GAAP operating income (loss)$24,509$75,892
Per diluted common share:
Net income (loss)$(0.01)$2.67
Effect of exclusions0.46(1.27)
Non-GAAP operating income (loss) per diluted common share$0.45$1.40

(1) Net investment gains (losses) in 2022 include a gain of $9.0 million related to the change in the fair value of contingent consideration issued in connection with the NORCAL acquisition. We have excluded this adjustment as it does not reflect normal operating results. See further discussion around the contingent consideration in Note 2 and Note 4 of the Notes to Consolidated Financial Statements.

(2) Net investment gains (losses) on investments related to SPCs are recognized in our Segregated Portfolio Cell Reinsurance segment. SPC results, including any net investment gain or loss, that are attributable to external cell participants are reflected in the SPC dividend expense (income). To be consistent with our exclusion of net investment gains (losses) recognized in earnings, we are excluding the portion of net investment gains (losses) that is included in the SPC dividend expense (income) which is attributable to the external cell participants.

(3) Transaction-related costs associated with our acquisition of NORCAL. We are excluding these costs as they do not reflect normal operating results and are unique and non-recurring in nature.

(4) Gain on bargain purchase associated with our acquisition of NORCAL which is considered unusual, infrequent and non-recurring in nature. As such, we have excluded the gain on bargain purchase as it does not reflect normal operating results.

(5) The 21% rate is the statutory tax rate associated with the taxable or tax deductible items listed above. The taxes associated with the net investment gains (losses) related to SPCs in our Segregated Portfolio Cell Reinsurance segment are paid by the individual SPCs and are not included in our consolidated tax provision or net income (loss); therefore, both the net investment gains (losses) from our Segregated Portfolio Cell Reinsurance segment and the adjustment to exclude the portion of net investment gains (losses) included in the SPC dividend expense (income) in the table above are not tax effected. The 2021 gain on bargain purchase and the 2022 gain related to the change in the fair value of contingent consideration are non-taxable and therefore had no associated income tax impact.

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Non-GAAP Operating ROE

Non-GAAP operating ROE is a financial measure that is calculated as Non-GAAP operating income (loss) for the period divided by the average of beginning and ending total GAAP shareholders’ equity. As previously discussed, in calculating Non-GAAP operating income (loss), we have excluded the effects of certain items that do not reflect normal results. Non-GAAP operating ROE measures the overall after-tax profitability of our insurance operations and shows how efficiently capital is being used; however, it should be considered in conjunction with ROE computed in accordance with GAAP. The following table is a reconciliation of ROE to Non-GAAP operating ROE for the years ended December 31, 2022 and 2021:

Year Ended December 31
20222021Change
ROE(1)%5.3%(5.3pts)
Pre-tax effect of items excluded in the calculation of Non-GAAP operating ROE2.6%0.2%2.4pts
Tax effect, at 21%(2)(0.7%)0.1%(0.8pts)
Non-GAAP operating ROE1.9%5.6%(3.7pts)
(1) The $74.4 million gain on bargain purchase recognized during the second quarter of 2021 was excluded in our calculation of ROE for the year ended December 31, 2021 consistent with our treatment of gains on bargain purchases from previous acquisitions.
(2) The 21% rate is the statutory tax rate associated with the taxable or tax deductible items. See further discussion in footnote 5 in this section under the heading "Non-GAAP Operating Income."

Non-GAAP operating ROE for 2022 decreased by 3.7 percentage points largely due to a decrease in our investment results from our portfolio of investments in LPs/LLCs (see previous discussion under the heading "Revenues"). Furthermore, the decrease in ROE for 2022 reflected a lower amount of prior year DPAC amortization associated with NORCAL policies than would have otherwise been recognized during 2021 due to the application of GAAP purchase accounting rules and a lower amount of favorable development as compared to 2021. See previous discussion in this section under the heading "Expenses" and further discussion in our Segment Operating Results sections that follow.

Non-GAAP Adjusted Book Value per Share

Book value per share is calculated as total GAAP shareholders’ equity divided by the total number of common shares outstanding at the balance sheet date. This ratio measures the net worth of the Company to shareholders on a per share basis.

Non-GAAP adjusted book value per share is a Non-GAAP measure widely used within the insurance sector and is calculated as shareholders’ equity, excluding AOCI, divided by the total number of common shares outstanding at the balance sheet date. This Non-GAAP calculation measures the net worth of the Company to shareholders on a per share basis excluding AOCI to eliminate the temporary and potentially significant effects of fluctuations in interest rates on our fixed income portfolio; however, it should be considered in conjunction with book value per share computed in accordance with GAAP. The increase in interest rates during 2022 lead to significant unrealized holding losses on our available-for-sale fixed maturity investments resulting in volatility in AOCI. See Note 12 of the Notes to Consolidated Financial Statements for additional information.

The following table is a reconciliation of our book value per share to Non-GAAP adjusted book value per share at December 31, 2022 and December 31, 2021:

Book Value Per Share
Book Value Per Share at December 31, 2021$26.46
Less: AOCI Per Share(1)0.30
Non-GAAP Adjusted Book Value Per Share at December 31, 202126.16
Increase (decrease) to Non-GAAP Adjusted Book Value Per Share during the year ended December 31, 2022 attributable to:
Dividends declared(0.20)
Net income (loss)(0.01)
Other(2)0.04
Non-GAAP Adjusted Book Value Per Share at December 31, 202225.99
Add: AOCI Per Share(1)(5.53)
Book Value Per Share at December 31, 2022$20.46
(1)Primarily the impact of accumulated unrealized investment gains (losses) on our available-for-sale fixed maturity investments. See Note 12 of the Notes to Consolidated Financial Statements for additional information.
(2) Includes the impact of share-based compensation and shares repurchased conducted through a 10b5-1 stock repurchase plan.

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Segment Results - Specialty Property & Casualty

Our Specialty P&C segment focuses on professional liability insurance and medical technology liability insurance as discussed in Note 16 of the Notes to Consolidated Financial Statements. On May 5, 2021, we completed our acquisition of NORCAL, an underwriter of healthcare professional liability insurance (Note 2 of the Notes to Consolidated Financial Statements provides additional information regarding this acquisition). Segment results reflected pre-tax underwriting profit or loss from these insurance lines and included the amortization of certain purchase accounting adjustments. Segment results for the years ended December 31, 2022 and 2021 exclude transaction-related costs and, for 2021, a $74.4 million gain on bargain purchase associated with our acquisition of NORCAL as we do not consider these items in assessing the financial performance of the segment. Segment results included the following:

Year Ended December 31
($ in thousands)20222021Change
Net premiums written$765,444$626,147$139,29722.2%
Net premiums earned$769,773$695,008$74,76510.8%
Other income5,0033,3701,63348.5%
Net losses and loss adjustment expenses(609,915)(575,164)(34,751)6.0%
Underwriting, policy acquisition and operating expenses(192,397)(127,709)(64,688)50.7%
Segment results$(27,536)$(4,495)$(23,041)(512.6%)
Net loss ratio79.2%82.8%(3.6pts)
Underwriting expense ratio25.0%18.4%6.6pts

Premiums Written

Changes in our premium volume within our Specialty P&C segment are generally driven by three primary factors: (1) the amount of new business written, (2) our retention of existing business and (3) the premium charged for business that is renewed, which is affected by rates charged and by the amount and type of coverage an insured chooses to purchase. In addition, premium volume may periodically be affected by shifts in the timing of renewals between periods. For the year ended December 31, 2022, our premium volume was primarily affected by our acquisition of NORCAL.

The medical professional liability market, which accounts for a majority of the revenues in this segment, remains challenging as physicians continue joining hospitals or larger group practices and, therefore, are no longer purchasing individual or group policies in the standard market. In addition, some competitors have chosen to compete primarily on price. Both factors may impact our ability to write new business and retain existing business. Furthermore, the insurance and reinsurance markets have historically been cyclical, characterized by extended periods of intense price competition and other periods of reduced capacity. The medical professional liability market has been particularly affected by these cycles. Underwriting cycles are driven, among other reasons, by excess capacity available to compete for the business. Changes in the frequency and severity of losses may also affect the cycles of the insurance and reinsurance markets significantly. During “soft markets” where price competition is high and underwriting profits are poor, growth and retention of business become challenging which may result in reduced premium volumes.

Gross, ceded and net premiums written were as follows:

Year Ended December 31
($ in thousands)20222021Change
Gross premiums written$836,628$681,509$155,11922.8%
Less: Ceded premiums written71,18455,36215,82228.6%
Net premiums written$765,444$626,147$139,29722.2%

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Gross Premiums Written

Gross premiums written by component were as follows:

Year Ended December 31
($ in thousands)20222021Change
Professional Liability
HCPL
Standard Physician(1)(12)$205,271$209,938$(4,667)(2.2%)
NORCAL Standard Physician(2)240,391111,673128,718115.3%
Total Standard Physician445,662321,611124,05138.6%
Specialty
Custom Physician(3)(12)49,93146,2103,7218.1%
NORCAL Custom Physician(4)30,14616,39413,75283.9%
Hospitals and Facilities(5)(12)56,12151,3104,8119.4%
NORCAL Hospitals and Facilities(6)12,8609,9552,90529.2%
Senior Care(7)(12)6,3546,708(354)(5.3%)
Reinsurance assumed(8)43,44937,7555,69415.1%
Total Specialty198,861168,33230,52918.1%
Total HCPL644,523489,943154,58031.6%
Small Business Unit(9)102,524103,083(559)(0.5%)
Tail Coverages(10)(12)29,00930,637(1,628)(5.3%)
NORCAL Tail Coverages(10)18,64616,0922,55415.9%
Total Professional Liability794,702639,755154,94724.2%
Medical Technology Liability(11)41,06540,997680.2%
Other86175710413.7%
Total Gross Premiums Written$836,628$681,509$155,11922.8%

(1) Standard Physician premium, exclusive of NORCAL, decreased in 2022 as compared to 2021 driven by retention losses and, to a lesser extent, the shifting of certain policies totaling $4.2 million from our Standard Physician line to our Custom Physician line of business during the second quarter of 2022. Partially offsetting these factors during 2022 was an increase in renewal pricing and, to a lesser extent, new business written. Retention losses during 2022 generally reflect our underwriting strategy as we emphasize careful risk selection, rate adequacy, improved contract terms and a willingness to walk away from business that does not fit our goal of achieving a long-term underwriting profit. Our underwriting and strategic planning process includes a continual evaluation of venues, specialties and other areas to improve our underwriting results. Renewal pricing increases during 2022 reflect the rising loss cost environment and new business written reflects the competitive market conditions.

(2) NORCAL Standard Physician premium represents premium contributed by NORCAL since the date of acquisition and is comprised of twelve month term policies and, to a lesser extent, three month term policies. NORCAL Standard Physician premium increased during 2022 driven by approximately four months of additional premium in 2022 as compared to 2021 due to the timing of our acquisition of NORCAL on May 5, 2021. The remaining increase in NORCAL Standard Physician premium during 2022 was due to an increase in renewal pricing, the conversion of a majority of the three month term policies to twelve month term policies and, to a lesser extent, new business written, partially offset by retention losses. Retention losses in 2022 were primarily attributable to price competition and the process of evaluating the NORCAL book of business and implementing ProAssurance's underwriting strategies.

(3) Custom Physician premium includes large physician groups, multi-state physician groups and non-standard physicians and is written primarily on an excess and surplus lines basis. Exclusive of NORCAL, the increase in Custom Physician premium in 2022 as compared to 2021 primarily reflected the shifting of certain policies totaling $4.2 million from our Standard Physician line of business. In addition, the increase reflected new business written, an increase in renewal pricing and, to a lesser extent, net timing differences of $1.3 million primarily related to the prior year renewal of a few policies, partially offset by retention losses. Renewal pricing increases for 2022 reflect pricing actions taken in response to a rising loss cost environment and new business written

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reflects the competitive market conditions. The retention rate in our Custom Physician book in 2022 reflects the impact of the loss of two large policies totaling $9.0 million due to the willingness of competitors to offer pricing and terms that did not meet our underwriting criteria during the first quarter of 2022, which resulted in a decrease to our Specialty retention rate of 5.4 percentage points.

(4) NORCAL Custom Physician premium represents premium contributed by NORCAL since the date of acquisition and includes large physician groups, multi-state physician groups and non-standard physicians and is written primarily on an excess and surplus lines basis. NORCAL Custom Physician premium increased during 2022 as compared to 2021 driven by approximately four months of additional premium during 2022 as compared to 2021 due to the timing of our acquisition of NORCAL on May 5, 2021. In addition, the increase in NORCAL Custom Physician premium during 2022 reflected an increase in renewal pricing and, to a lesser extent, new business written, partially offset by retention losses. Retention losses during 2022 reflect the loss of a $2.2 million policy during the second quarter of 2022 due to price competition as well as our evaluation of the NORCAL book of business and implementing ProAssurance's underwriting strategies.

(5) Hospitals and Facilities premium, exclusive of NORCAL, (which includes hospitals, surgery centers and miscellaneous medical facilities) increased in 2022 as compared to 2021 driven by new business written, primarily miscellaneous medical facilities, and, to a lesser extent, an increase in renewal pricing, partially offset by retention losses. Retention losses in 2022 were largely attributable to the loss of a $1.4 million policy due to the insured entering into a captive arrangement and our non-renewal of a $1.2 million policy during the first quarter of 2022 due to our focus on underwriting discipline. Renewal pricing increases in 2022 reflect rate increases and contract modifications that we believe are appropriate given the current loss environment and new business written reflects the competitive market conditions.

(6) NORCAL Hospitals and Facilities premium represents premium contributed by NORCAL since the date of acquisition and includes hospitals, surgery centers and miscellaneous medical facilities. NORCAL Hospitals and Facilities premium increased in 2022 as compared to 2021 driven by approximately four months of additional premium during 2022 as compared to 2021 due to the timing of our acquisition of NORCAL on May 5, 2021. In addition, the increase in NORCAL Hospitals and Facilities premium in 2022 as compared to 2021 reflected new business written and, to a lesser extent, an increase in renewal pricing, partially offset by retention losses. Retention losses in 2022 are largely attributable to the process of evaluating the NORCAL book of business and implementing ProAssurance's underwriting strategies.

(7) Senior Care premium includes facilities specializing in long term residential care primarily for the elderly ranging from independent living through skilled nursing. Our Senior Care premium remained relatively unchanged in 2022 as compared to 2021 as retention losses were offset by new business written and, to a lesser extent, an increase in renewal pricing. The lower premium retention in 2022 was primarily due to a large account renewing with a meaningful reduction in exposure driven by a reduction in the number of facilities.

(8) We offer custom alternative risk solutions including assumed reinsurance. The increase in premium in 2022 reflected an increase in premiums assumed on a quota share basis through a strategic partnership in place since 2016 with an international medical professional liability insurer. In 2021, we increased our participation in the original program and entered into another program with this insurer in a new international territory. We anticipate the volume of premium assumed through this partnership will continue to grow going forward. In addition, the increase in 2022 reflected an assumed reinsurance arrangement with a regional hospital group entered into during the third quarter of 2022 totaling $1.3 million. The increase in premium in 2022 as compared to 2021 was partially offset by the impact of a prior year assumed reinsurance arrangement with a regional hospital group which resulted in $4.5 million of premium written, comprised of $2.3 million of retroactive premium written and fully earned and $2.2 million of prospective premium written. Furthermore, premium in both 2022 and 2021 reflected the annual renewal of this arrangement during the third quarter.

(9) Our Small Business Unit is comprised of premium associated with podiatrists, legal professionals, dentists and chiropractors. Our Small Business Unit premium remained relatively unchanged in 2022 as compared to 2021 as an increase in renewal pricing and new business written were offset by retention losses. The increase in renewal pricing in 2022 was primarily the result of an increase in the rate charged for certain renewed policies in select states.

(10) We offer extended reporting endorsement or "tail" coverage to insureds who discontinue their claims-made coverage with us, and we also periodically offer tail coverage through stand-alone policies. Tail coverage premiums are generally 100% earned in the period written because the policies insure only incidents that occurred in prior periods and are not cancellable. The amount of tail coverage premium written can vary significantly from period to period.

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(11) Our Medical Technology Liability business is marketed throughout the U.S.; coverage is typically offered on a primary basis, within specified limits, to manufacturers and distributors of medical technology and life sciences products including entities conducting human clinical trials. In addition to the previously listed factors that affect our premium volume, our Medical Technology Liability premium is also impacted by the sales volume of insureds. Our Medical Technology Liability premium remained relatively unchanged in 2022 as compared to 2021 as retention losses were more than offset by new business written and an increase in renewal pricing. Renewal pricing increases in 2022 are primarily due to changes in the sales volume and changes in exposure of certain insureds. Retention losses in 2022 are primarily attributable to insureds no longer needing coverage, an increase in competition on terms and pricing, as well as merger activity within the industry.

(12) Certain components of our gross premiums written include alternative market premiums. We currently cede either all or a portion of the alternative market premium, net of reinsurance, to three SPCs of our wholly owned Cayman Islands reinsurance subsidiaries, Inova Re and Eastern Re, which are reported in our Segregated Portfolio Cell Reinsurance segment (see further discussion in the Ceded Premiums Written section that follows). The portion not ceded to the SPCs is retained within our Specialty P&C segment.

Year Ended December 31
($ in millions)20222021Change
Standard Physician$$2.0$(2.0)nm
Custom Physician2.02.0nm
Hospitals and Facilities0.10.1%
Senior Care4.85.2(0.4)(7.7%)
Tail Coverages4.90.84.1512.5%
Total$11.8$8.1$3.745.7%

Alternative market gross premiums written increased in 2022 as compared to 2021 driven by an increase in tail coverage premium, primarily related to one program. Additionally, alternative market gross premiums during 2022 reflected a $2.0 million expiring Standard Physician policy in one program renewed as a Custom Physician policy during the second quarter of 2022.

We are committed to a rate structure that will allow us to fulfill our obligations to our insureds, while generating competitive long-term returns for our shareholders. Our pricing continues to be based on expected losses as indicated by our historical loss data and available industry loss data. In recent years, this practice has resulted in rate increases and we anticipate further rate increases due to indications of increasing projected loss severity. Additionally, the pricing of our business includes the effects of filed rates, surcharges and discounts. Renewal pricing reflects changes in our exposure base, deductibles, self-insurance retention limits and other policy terms and conditions. See further explanation of changes in renewal pricing above under the heading "Gross Premiums Written".

The change in renewal pricing for our Specialty P&C segment, including by major component, was as follows:

Year Ended December 31
2022
Specialty P&C segment7%
HCPL
Standard Physician7%
Specialty10%
Total HCPL8%
Small Business Unit6%
Medical Technology Liability3%

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New business written by major component on a direct basis was as follows:

Year Ended December 31
(In millions)20222021
HCPL
Standard Physician$9.8$4.7
Specialty19.128.2
Total HCPL28.932.9
Small Business Unit3.83.9
Medical Technology Liability4.66.5
Total$37.3$43.3

For our Specialty P&C segment, we calculate retention as annualized renewed premium divided by all annualized premium subject to renewal. Retention is affected by a number of factors. We may lose insureds to competitors or to alternative insurance mechanisms such as risk retention groups, captive arrangements or self-insurance entities (often when physicians join hospitals or large group practices) or due to pricing or other issues. We may choose not to renew an insured as a result of our underwriting evaluation. Insureds may also terminate coverage because they have left the practice of medicine for various reasons, principally for retirement, death or disability, but also for personal reasons. See further explanation of changes in retention above under the heading "Gross Premiums Written".

Retention for our Specialty P&C segment, including by major component, was as follows:

Year Ended December 31
20222021
Specialty P&C segment84%80%
HCPL
Standard Physician88%86%
Specialty69%58%
Total HCPL82%77%
Small Business Unit91%91%
Medical Technology Liability90%90%

Ceded Premiums Written

Ceded premiums represent the amounts owed to our reinsurers for their assumption of a portion of our losses. Our HCPL and Medical Technology Liability excess of loss reinsurance arrangements renew annually on October 1. Through our current excess of loss reinsurance arrangements which renewed effective October 1, 2022, we generally retain the first $2 million in risk insured by us and cede coverages in excess of this amount. For our HCPL coverages in excess of $2 million, we generally retain from 0% to 5% of the next $24 million of risk. There were no significant changes in the cost or structure of our HCPL treaty upon the October 2022 renewal. Our HCPL excess of loss reinsurance arrangement that renewed on October 1, 2021 renewed at a lower gross rate and prospectively incorporated NORCAL policies. Prior to October 1, 2021, NORCAL policies were reinsured under separate reinsurance agreements, primarily excess of loss, which have historically renewed annually on January 1. For the NORCAL excess of loss reinsurance arrangement that renewed on January 1, 2021, retention was generally the first $2 million in risk and coverages in excess of this amount were ceded up to $24 million. For our Medical Technology Liability treaty which also renewed effective October 1, 2022, we do not retain any of the next $8 million of risk for coverages in excess of $2 million.

We pay our reinsurers a ceding premium in exchange for their accepting the risk, and in certain of our excess of loss arrangements, the ultimate amount of which is determined by the loss experience of the business ceded, subject to certain minimum and maximum amounts. Given the length of time that it takes to resolve our claims, many years may elapse before all losses recoverable under a reinsurance arrangement are known. As a part of the process of estimating our loss reserve we also make estimates regarding the amounts recoverable under our reinsurance arrangements. As a result, we may have an adjustment to our estimate of expected losses and associated recoveries for prior year ceded losses under certain loss sensitive reinsurance agreements. Any changes to estimates of premiums ceded related to prior accident years are fully earned in the period the changes in estimates occur.

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Ceded premiums written were as follows:

Year Ended December 31
($ in thousands)20222021Change
Excess of loss reinsurance arrangements (1)$38,005$30,622$7,38324.1%
Other shared risk arrangements (2)19,04916,1122,93718.2%
Premium ceded to SPCs (3)10,9027,2113,69151.2%
NORCAL premiums ceded since acquisition (4)2,253(2,253)nm
Other ceded premiums written (5)6,0563,1002,95695.4%
Adjustment to premiums owed under reinsurance agreements, prior accident years, net (6)(2,828)(3,936)1,108(28.2%)
Total ceded premiums written$71,184$55,362$15,82228.6%

(1)We generally reinsure risks under our excess of loss reinsurance arrangements pursuant to which the reinsurers agree to assume all or a portion of all risks that we insure above our individual risk retention levels. Premium due to reinsurers is based on a rate factor applied to gross premiums written subject to cession under the arrangement. The increase in ceded premiums written under our excess of loss reinsurance arrangements was driven by the incorporation of NORCAL policies into our existing HCPL excess of loss reinsurance arrangements with the October 1, 2021 renewal, as previously discussed, which contributed $11.2 million of ceded premiums in 2022 as compared to $1.9 million in 2021. Excluding NORCAL, ceded premiums written under our excess of loss reinsurance arrangements decreased by approximately $1.9 million in 2022 as compared to 2021 primarily due to a decrease in the overall volume of gross premiums written subject to cession and, to a lesser extent, the higher retention and reduced rate on the treaty year effective October 1, 2021.

(2)We have entered into various shared risk arrangements, including quota share, fronting and captive arrangements, with certain large healthcare systems and other insurance entities. While we cede a large portion of the premium written under these arrangements, they provide us an opportunity to grow net premium through strategic partnerships. These arrangements primarily include our Ascension Health program. The increase in ceded premiums written under our shared risk arrangements in 2022 as compared to 2021 was primarily due to an increase in premium ceded to our Ascension Health Program.

(3)As previously discussed, as a part of our alternative market solutions, all or a portion of certain healthcare premium written is ceded to SPCs in our Segregated Portfolio Cell Reinsurance segment under either excess of loss or quota share reinsurance agreements, depending on the structure of the individual program. See the Segment Results - Segregated Portfolio Cell Reinsurance section for further discussion on the cession to the SPCs from our Specialty P&C segment. Premiums ceded to SPCs in 2022 increased as compared to 2021 driven by the impact of tail coverages, primarily related to one program (see previous discussion in footnote 12 under the heading "Gross Premiums Written").

(4)NORCAL policies written prior to October 1, 2021 were reinsured under separate reinsurance agreements, primarily excess of loss; however, these policies were incorporated into our existing HCPL excess of loss reinsurance arrangements with the October 1, 2021 renewal, as previously discussed. For NORCAL's previous excess of loss agreement, deposit ceded premium, as defined in the contract, was initially estimated and recorded at the inception date of the treaty, generally January 1, as an estimate of ceded premiums written for the full contract year based on information provided by brokers and reinsurers. As a result, the majority of ceded premiums for NORCAL's excess of loss reinsurance arrangement were recorded by NORCAL before the acquisition in their first quarter 2021 results and were expensed pro rata throughout the contract year. However, these initial estimates of ceded premiums were periodically adjusted as new information was received and were fully earned in the period the changes in estimates occurred. NORCAL's ceded premiums written in 2021 related almost entirely to an increase in the estimate of premiums owed in excess of the deposit ceded premium initially recorded by NORCAL prior to acquisition and, to a lesser extent, premium related to cyber liability coverages.

(5)The increase in other ceded premiums written in 2022 as compared to 2021 was primarily driven by the incorporation of NORCAL's cyber liability coverages into our existing HCPL cyber liability arrangement with the January 1, 2022 renewal.

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(6)Given the length of time that it takes to resolve our claims, many years may elapse before all losses recoverable under a reinsurance arrangement are known. As a part of the process of estimating our loss reserve we also make estimates regarding the amounts recoverable under our reinsurance arrangements. As previously discussed, the premiums ultimately ceded under certain of our swing rated excess of loss reinsurance arrangements are subject to the losses ceded under the arrangements. As part of the review of our reserves for 2022 and 2021, we recorded a net decrease in our estimate of expected losses and associated recoveries for prior year ceded losses, as well as our estimate of ceded premiums owed to reinsurers. Changes to estimates of premiums ceded related to prior accident years are fully earned in the period the changes in estimates occur.

Ceded Premiums Ratio

As shown in the table below, our ceded premiums ratio was affected in both 2022 and 2021 by revisions to our estimate of premiums owed to reinsurers related to coverages provided in prior accident years. The ceded premiums ratio was as follows:

Year Ended December 31
20222021Change
Ceded premiums ratio8.5%8.1%0.4pts
Less the effect of adjustments in premiums owed under reinsurance agreements, prior accident years (as previously discussed)(0.3%)(0.6%)0.3pts
Ratio, current accident year8.8%8.7%0.1pts

The above table reflects ceded premiums written, excluding the effect of prior year ceded premium adjustments, as previously discussed, as a percent of gross premiums written. Our ceded premiums ratio remained relatively unchanged for 2022 as compared to 2021. See additional discussion above under the heading "Ceded Premiums Written."

Net Premiums Earned

Net premiums earned consist of gross premiums earned less the portion of earned premiums that we cede to our reinsurers for their assumption of a portion of our losses. Because premiums are generally earned pro rata over the entire policy period, fluctuations in premiums earned tend to lag those of premiums written. The majority of our policies carry a term of one year; however, some of our Medical Technology Liability policies have a multi-year term and some of our NORCAL Standard Physician policies have a three-month term. In addition, prior to the third quarter of 2020, we wrote certain Standard Physician policies with a twenty-four month term. Tail coverage premiums are generally 100% earned in the period written because the policies insure only incidents that occurred in prior periods and are not cancellable. Retroactive coverage premiums are 100% earned at the inception of the contract, as all of the associated underlying loss events occurred in the past. Additionally, any ceded premium changes due to changes to estimates of premiums owed under reinsurance agreements for prior accident years are fully earned in the period of change.

Net premiums earned were as follows:

Year Ended December 31
($ in thousands)20222021Change
Gross premiums earned$834,500$761,411$73,0899.6%
Less: Ceded premiums earned64,72766,403(1,676)(2.5%)
Net premiums earned$769,773$695,008$74,76510.8%

Gross premiums earned included earned premium from our acquisition of NORCAL of approximately $296.5 million in 2022 as compared to $226.0 million in 2021. Excluding NORCAL premiums, gross premiums earned increased $2.6 million in 2022 as compared to 2021 driven by our focus on rate adequacy.

Ceded premiums earned during both 2022 and 2021 included prior accident year ceded premium adjustments under swing rated reinsurance agreements (see previous discussion in footnote 6 under the heading "Ceded Premiums Written"). After removing the effect of prior accident year ceded premium adjustments from both years, ceded premiums earned decreased $2.8 million in 2022 as compared to 2021 driven by a decrease in premium ceded under our shared risk arrangements during the preceding twelve months, partially offset by the pro rata effect of an increase in premium ceded under our excess of loss arrangements during the preceding twelve months.

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Losses and Loss Adjustment Expenses

The determination of calendar year losses involves the actuarial evaluation of incurred losses for the current accident year and the actuarial re-evaluation of incurred losses for prior accident years.

Accident year refers to the accounting period in which the insured event becomes a liability of the insurer. For claims-made policies, which represent the majority of the premiums written in our Specialty P&C segment, the insured event generally becomes a liability when the event is first reported to us and the policy that is in effect at that time covers the claim. For occurrence policies, the insured event becomes a liability when the event takes place even though the claim may be reported to us at a later date. For retroactive coverages, the insured event becomes a liability at inception of the underlying contract. We believe that measuring losses on an accident year basis is the best measure of the underlying profitability of the premiums earned in that period, since it associates policy premiums earned with the estimate of the losses incurred related to those policy premiums.

The following table summarizes calendar year net loss ratios for our Specialty P&C segment by separating losses between the current accident year and all prior accident years. The net loss ratios for our Specialty P&C segment were as follows:

Net Loss Ratios (1)
Year Ended December 31
20222021Change
Calendar year net loss ratio79.2%82.8%(3.6pts)
Less impact of prior accident years on the net loss ratio(3.9%)(4.7%)0.8pts
Current accident year net loss ratio(2)83.1%87.5%(4.4pts)

(1)Net losses, as specified, divided by net premiums earned.

(2)For the year ended December 31, 2022, our current accident year net loss ratio (as shown in the table above), improved 4.4 percentage points as compared to 2021. The change in our current accident year net loss ratio was primarily attributable to the following:

(In percentage points)Increase (Decrease) 2022 versus 2021
Estimated ratio increase (decrease) attributable to:
NORCAL Operations(2.2 pts)
NORCAL Acquisition - Purchase Accounting Amortization0.3 pts
Change in Estimate of ULAE(3.3 pts)
Ceded Premium Adjustments, Prior Accident Years0.2 pts
All other, net0.6 pts
Decrease in current accident year net loss ratio(4.4 pts)

•Excluding the impact of the items specifically identified in the table above, our current accident year net loss ratio increased 0.6 percentage points during 2022 as compared to 2021 driven by actuarial analyses performed by both internal and consulting actuaries during 2022. We update and review the data underlying the estimation of our current accident year reserve each reporting period and make adjustments to current accident year net loss ratios that we believe best reflect emerging data. Both our internal and consulting actuaries perform an in-depth review of our current accident year reserve on at least a semiannual basis. As a result of these analyses in 2022, we increased our current accident year net loss ratio, excluding NORCAL, driven by an increase to certain expected loss ratios in our Standard Physician line of business due to higher than anticipated loss severity trends in select jurisdictions, which emerged primarily in the fourth quarter of 2022. The increase in our current accident year net loss ratio was partially offset by our reduction to certain expected loss ratios during the first quarter of 2022 in our Standard Physician and Specialty lines of business primarily reflecting the improvement in pricing and terms that we have obtained in our estimate of expected losses.

•Initial expected loss ratios associated with NORCAL policies are higher than the average for our other books of business in this segment; however, we reduced certain expected NORCAL loss ratios during the fourth quarter of 2021 and also in the third and fourth quarters of 2022 due to favorable frequency trends, some of which, we believe, are attributable to our re-underwriting efforts, leading to a 2.2 percentage point improvement in our segment current accident year net loss ratio in 2022. We completed the process of evaluating the NORCAL book of business and implementing ProAssurance's underwriting strategies during the second quarter of 2022. Furthermore, the 2.2

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percentage point improvement also reflected a reduction to our reserve related to NORCAL's DDR coverage endorsements in the fourth quarter of 2022.

•Also as a result of our acquisition of NORCAL, our current accident year net loss ratio in 2022 and 2021 was impacted by the purchase accounting amortization of the negative VOBA associated with NORCAL's assumed unearned premium of $4.9 million and $6.7 million, respectively, which is recorded as a reduction to current accident year net losses. As of June 30, 2022, the negative VOBA was fully amortized which resulted in a 0.3 percentage point increase in our current period ratio as compared to the prior year period.

•Beginning in 2022, we revised our process of estimating ULAE as a result of substantially integrating NORCAL into our Specialty P&C segment operations, which accounted for a 3.3 percentage point decrease in our current accident year net loss ratio in 2022 with an offsetting 3.3 percentage point increase in our current period expense ratio with no impact to our combined ratio or segment results during the year ended December 31, 2022 (see discussion on our expense ratio in the following section under the heading "Underwriting, Policy Acquisition and Operating Expenses").

•In 2022 and 2021, we decreased our estimate of premiums owed under reinsurance agreements related to prior accident years which increased net premium earned (the denominator of the current accident year net loss ratio) and accounted for a 0.2 percentage point increase in our current period ratio. See the previous discussion under the heading "Ceded Premiums Written" for additional information.

We re-evaluate our previously established reserve each quarter based upon the most recently completed actuarial analysis supplemented by any new analysis, information or trends that have emerged since the date of that study. We also take into account currently available industry trend information.

The following table shows the components of our net prior accident year reserve development:

Year Ended December 31
($ in thousands)20222021Change
Net favorable reserve development$19,000$25,035$(6,035)(24.1%)
NORCAL Acquisition - Purchase Accounting Amortization*10,8197,9072,91236.8%
Total net favorable reserve development$29,819$32,942$(3,123)(9.5%)
*See Note 2 of the Notes to Consolidated Financial Statements for additional information on the amortization of the NORCAL acquisition purchase accounting adjustments.

•Development recognized during 2022 principally related to accident years 2017 and 2020 through 2021. Net favorable prior accident year reserve development recognized in 2022 included favorable development related to NORCAL's 2021 accident year and, to a lesser extent, our Medical Technology Liability line of business. Net favorable prior accident year reserve development recognized in 2022 was partially offset by unfavorable reserve development in our HCPL line of business, excluding NORCAL, driven by higher than anticipated loss severity trends in select jurisdictions, which emerged primarily in the fourth quarter of 2022. We have not recognized any development related to NORCAL's accident years 2020 or prior since the date of acquisition on May 5, 2021 based on our comparison of expected loss emergence to actual loss emergence.

•Development recognized in 2021 primarily reflected lower than anticipated loss emergence, principally related to accident years 2015 through 2020.

•We reduced our prior accident year IBNR reserve for COVID-19 by $9.0 million and $1.0 million during 2022 and 2021, respectively, as early first notices of potential claims related to anticipated COVID losses have not turned into claims. As of December 31, 2022, we no longer carry a specific IBNR reserve for potential COVID-19 related losses. See additional discussion on the COVID-19 IBNR reserve in our Critical Accounting Estimates section under the heading "Reserve for Losses and Loss Adjustment Expenses."

•Net favorable development recognized in 2022 included an increase of $4.0 million and $1.0 million in our reserve for potential ECO/XPL claims in 2022 and 2021, respectively.

A detailed discussion of factors influencing our recognition of loss development is included in our Critical Accounting Estimates section under the heading "Reserve for Losses and Loss Adjustment Expenses." Assumptions used in establishing our reserve are regularly reviewed and updated by management as new data becomes available. Any adjustments necessary are reflected in the then current operations. Due to the size of our reserve, even a small percentage adjustment to the assumptions can have a material effect on our results of operations for the period in which the change is made, as was the case in both 2022 and 2021.

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Underwriting, Policy Acquisition and Operating Expenses

Our Specialty P&C segment underwriting, policy acquisition and operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20222021Change
DPAC amortization$91,660$61,662$29,99848.6%
Management fees4,7633,78198226.0%
Other underwriting and operating expenses95,97462,26633,70854.1%
Total$192,397$127,709$64,68850.7%

DPAC amortization for 2022 increased due to a higher amount of premiums written driven by our 2021 acquisition of NORCAL. Due to the NORCAL acquisition and application of GAAP purchase accounting rules, the level of DPAC amortization in 2021 was approximately $13.4 million lower than would have otherwise been recognized. Under these purchase accounting rules, the capitalized policy acquisition costs for policies written prior to the acquisition date were written off through purchase accounting on May 5, 2021 rather than being expensed pro rata over the remaining term of the associated policies. DPAC amortization associated with NORCAL policies in 2022 is approximately $1.0 million lower than would have otherwise been recognized for the period. The remaining increase in DPAC amortization for 2022 as compared to 2021 reflected an increase in agency commissions due to a higher volume of commissionable premium driven by NORCAL and an increase in compensation-related expenses driven by an increase in headcount due to the addition of NORCAL employees.

Management fees are charged pursuant to a management agreement by the Corporate segment to the operating subsidiaries within our Specialty P&C segment for services provided based on the extent to which services are provided to the subsidiary and the amount of premium written by the subsidiary. Fluctuations in the amount of premium written by each subsidiary can result in corresponding variations in the management fee charged to each subsidiary during a particular period. Due to continued organizational structure enhancements in our Specialty P&C segment during 2021 as well as operational alignments as a result of the integration of NORCAL, the extent to which services are provided exclusively by the Corporate segment to the operating subsidiaries within the segment decreased further effective January 1, 2022. Accordingly, we reduced the fee charged to the operating subsidiaries in 2022. Also effective January 1, 2022, the management agreement included the wholly owned operating subsidiaries of NORCAL contributing to $1.3 million of additional management fees in 2022.

Other underwriting and operating expenses increased in 2022 primarily due to a revision to our process of estimating ULAE which resulted in approximately $25.4 million of expenses remaining in operating expenses instead of being allocated to net losses and loss adjustment expenses. As a result, this change in ULAE estimate had offsetting impacts to our loss and expense ratios during 2022 with no impact to our combined ratio or segment results. See additional discussion on this change in ULAE estimate in the previous section under the heading "Losses and Loss Adjustment Expenses." Excluding the impact of the change in ULAE, other underwriting and operating expenses increased in 2022 as compared to 2021. The increase in 2022 was primarily attributable to higher amounts accrued for performance-related incentive plans due to our improved performance metrics, an increase in professional fees, as well as certain one-time expenses of $3.9 million, partially offset by the benefits from prior organizational restructurings and proactive expense management as well as expense synergies recognized from the NORCAL acquisition. The increase in professional fees in 2022 was primarily attributable to an increase in IT consulting fees. One-time expenses in 2022 were mainly comprised of one-time bonuses, accelerated depreciation associated with a decommissioned IT system, employee severance charges and lease exit costs.

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Underwriting Expense Ratio (the Expense Ratio)

Our expense ratio for the Specialty P&C segment was as follows:

Year Ended December 31
20222021Change
Underwriting expense ratio25.0%18.4%6.6pts

The change in our expense ratio in 2022 as compared to 2021 was primarily attributable to the following:

(In percentage points)Increase (Decrease) 2022 versus 2021
Estimated ratio increase (decrease) attributable to:
Change in Net Premiums Earned and DPAC amortization1.5 pts
NORCAL DPAC Amortization - Prior Period Purchase Accounting Impact1.9 pts
Change in Estimate of ULAE3.3 pts
One-Time Expenses0.5 pts
All other, net(0.6 pts)
Increase in the underwriting expense ratio6.6 pts

Excluding the impact of the items specifically identified in the table above, our expense ratio improved in 2022 by 0.6 percentage points primarily due to the benefits from prior organizational restructurings and proactive expense management as well as expense synergies recognized from the NORCAL acquisition, partially offset by higher amounts accrued for performance-related incentive plans and, to a lesser extent, an increase in professional fees, as previously discussed. As shown in the table above, the higher expense ratio for 2022 as compared to 2021 reflects the impact of purchase accounting on prior year DPAC amortization, the current year change in estimate of ULAE and the impact of one-time expenses, as previously discussed. The increase in the expense ratio from higher DPAC amortization, excluding the prior year purchase accounting impact, in relation to net premiums earned for 2022 of 1.5 percentage points primarily reflects an increase in agency commissions due to a higher volume of commissionable premium driven by NORCAL.

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Segment Results - Workers' Compensation Insurance

Our Workers' Compensation Insurance segment includes workers' compensation products provided to employers generally with 1,000 or fewer employees, as discussed in Note 16 of the Notes to Consolidated Financial Statements. Workers' compensation products offered include guaranteed cost policies, policyholder dividend policies, retrospectively-rated policies, deductible policies and alternative market programs. Alternative market programs include services related to program design, fronting, claims administration, risk management, SPC rental, asset management and SPC management services. Alternative market program premiums are 100% ceded to either the SPCs within our Segregated Portfolio Cell Reinsurance segment or captive insurers unaffiliated with ProAssurance for two programs. Our Workers' Compensation Insurance segment results reflect pre-tax underwriting profit or loss from these workers' compensation products, exclusive of investment results, which are included in our Corporate segment. Segment results included the following:

Year Ended December 31
($ in thousands)20222021Change
Net premiums written$160,760$161,865$(1,105)(0.7%)
Net premiums earned$166,371$164,600$1,7711.1%
Other income2,2012,211(10)(0.5%)
Net losses and loss adjustment expenses(111,407)(114,704)3,297(2.9%)
Underwriting, policy acquisition and operating expenses(54,737)(52,418)(2,319)4.4%
Segment results$2,428$(311)$2,739(880.7%)
Net loss ratio67.0%69.7%(2.7 pts)
Underwriting expense ratio32.9%31.8%1.1 pts

Premiums Written

Our workers’ compensation premium volume is driven by five primary factors: (1) the amount of new business written, (2) retention of our existing book of business, (3) premium rates charged on our renewal book of business, (4) changes in payroll exposure and (5) audit premium.

Gross, ceded and net premiums written were as follows:

Year Ended December 31
($ in thousands)20222021Change
Gross premiums written$247,132$240,546$6,5862.7%
Less: Ceded premiums written86,37278,6817,6919.8%
Net premiums written$160,760$161,865$(1,105)(0.7%)

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Gross Premiums Written

Gross premiums written by product were as follows:

Year Ended December 31
($ in thousands)20222021Change
Traditional business:
Guaranteed cost$135,847$138,756$(2,909)(2.1%)
Policyholder dividend21,54721,468790.4%
Deductible4,7054,613922.0%
Retrospective(1)3,1232,74138213.9%
Other7,2866,35792914.6%
Change in EBUB estimate1,450(1,210)2,660219.8%
Total traditional business173,958172,7251,2330.7%
Alternative market business(2)73,17467,8215,3537.9%
Total$247,132$240,546$6,5862.7%

(1) The change in retrospectively-rated policies included an adjustment that decreased premium by $1.7 million and $1.1 million during the years ended December 31, 2022 and 2021, respectively.

(2) A majority of alternative market premiums are ceded to SPCs in our Segregated Portfolio Cell Reinsurance segment. See further discussion on alternative market gross premiums written in our Segment Operating Results - Segregated Portfolio Cell Reinsurance section under the heading "Gross Premiums Written" that follows.

Gross premiums written increased during the year ended December 31, 2022 as compared to 2021, primarily reflecting higher audit premium and changes in the carried EBUB estimate, partially offset by lower renewal and new business premium. Policy audits processed in 2022 resulted in audit premium billed to policyholders totaling $13.6 million as compared to audit premium returned to policyholders totaling $0.8 million in 2021. The 2022 audit premium results reflect higher payrolls related to an increased workforce, as well as wage inflation, in our policyholders' businesses. Additionally, the carried EBUB estimate was increased $1.5 million in 2022 as compared to a reduction of $1.2 million in 2021. The increase in the carried EBUB estimate during 2022 reflects management's expectation of higher audited payrolls related to wage inflation. Our new business premium, renewal retention and rate change results in 2022 were reflective of the competitive workers' compensation market conditions. Renewal retention in our traditional business was impacted by the loss of a large account with expiring premium totaling $3.8 million, which decreased the renewal retention 2.2 percentage points.

We retained 100% of the twenty-three workers' compensation alternative market programs that were up for renewal during the year ended December 31, 2022. We wrote one new workers' compensation alternative market program with an unaffiliated captive insurer during 2022 with premiums written totaling $1.9 million. The policies in this program were written in our traditional book of business during 2021; therefore, there was no impact to gross premiums written in 2022.

New business, audit premium, renewal retention and renewal price changes for our traditional business and the alternative market business are shown in the table below:

Year Ended December 31
20222021
($ in millions)Traditional BusinessAlternative Market BusinessSegment ResultsTraditional BusinessAlternative Market BusinessSegment Results
New business$14.1$3.6$17.7$17.8$3.3$21.1
Audit premium (excluding EBUB)$8.2$5.4$13.6$(1.9)$1.1$(0.8)
Retention rate (1)82%87%83%86%89%87%
Change in renewal pricing (2)(5%)(4%)(5%)(1%)(4%)(2%)
(1) We calculate our workers' compensation retention rate as annualized expiring renewed premium divided by all annualized expiring premium subject to renewal. Our retention rate can be impacted by various factors, including price or other competitive issues, insureds being acquired, or a decision not to renew based on our underwriting evaluation.
(2) The pricing of our business includes an assessment of the underlying policy exposure and market conditions. We continue to base our pricing on expected losses, as indicated by our historical loss data.

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Ceded Premiums Written

Ceded premiums written were as follows:

Year Ended December 31
($ in thousands)20222021Change
Premiums ceded to SPCs(1)$68,035$64,639$3,3965.3%
Premiums ceded to external reinsurers(2)14,17712,7681,40911.0%
Premiums ceded to unaffiliated captive insurers(1)5,1393,1821,95761.5%
Change in return premium estimate under external reinsurance(3)297(605)902(149.1%)
Estimated revenue share under external reinsurance(4)(1,276)(1,303)27(2.1%)
Total ceded premiums written$86,372$78,681$7,6919.8%
(1) Represents alternative market business that is ceded under 100% quota share reinsurance agreements to the SPCs in our Segregated Portfolio Cell Reinsurance segment. Premiums ceded to unaffiliated captive insurers represent alternative market business for two programs that are ceded under 100% quota share reinsurance agreements. See further discussion on alternative market gross premiums written in our Segment Operating Results - Segregated Portfolio Cell Reinsurance section under the heading "Gross Premiums Written" that follows.
(2) Under our external reinsurance treaty for traditional business, we retain the first $0.5 million in risk insured by us and cede losses in excess of this amount on each loss occurrence, subject to an AAD, equal to 3.5% of subject earned premium for the treaty year effective May 1, 2022. Premiums ceded under our traditional reinsurance treaty are based on premiums earned during the treaty period.
(3) Changes in the return premium estimate reflect adjustments to our estimate of expected future recovery of ceded premium based on the underlying loss experience of our reinsurance treaties that include a provision for return premium.
(4) We are party to a revenue sharing agreement with our reinsurance broker under which we participate in the broker's revenue earned under our reinsurance treaties based on the volume of premium ceded. We estimate the amount of revenue we expect to receive under this agreement as premiums are recognized and ceded to the reinsurers.

Ceded premiums written increased during the year ended December 31, 2022 as compared to the year ended December 31, 2021, primarily reflecting higher alternative market premiums ceded to the Segregated Portfolio Cell Reinsurance segment and unaffiliated captive insurers as well as an increase in reinsurance rates under our external reinsurance treaty. The increase in premiums ceded to unaffiliated captive insurers in 2022 as compared to 2021 reflects the new alternative market program written in 2022 (see previous discussion under the heading "Gross Premiums Written").

Ceded Premiums Ratio

Ceded premiums ratio was as follows:

Year Ended December 31
20222021Change
Ceded premiums ratio, as reported34.1%32.4%1.7pts
Less the effect of:
Premiums ceded to SPCs (100%)24.6%24.6%pts
Premiums ceded to unaffiliated captive insurers (100%)2.2%1.7%0.5pts
Estimated revenue share(0.7%)(0.7%)pts
Assumed premiums earned (not ceded to external reinsurers)(0.3%)(0.2%)(0.1pts)
Ceded premiums ratio (related to external reinsurance), less the effects of above8.3%7.0%1.3pts

The above table reflects traditional ceded premiums earned as a percent of traditional gross premiums earned. As discussed above, premiums ceded under our traditional reinsurance treaty are based on premiums earned during the treaty period. The increase in the ceded premiums ratio in 2022 as compared to 2021 primarily reflected the higher reinsurance rates and a decrease in the estimated return premium.

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Net Premiums Earned

Net premiums earned consist of gross premiums earned less the portion of earned premiums that we cede to SPCs in our Segregated Portfolio Cell Reinsurance segment, external reinsurers (including changes related to the return premium and revenue share estimates) and the unaffiliated captive insurers. Because premiums are generally earned pro rata over the entire policy period, fluctuations in premiums earned tend to lag those of premiums written. Our workers’ compensation policies are twelve month term policies, and premiums are earned on a pro rata basis over the policy period. Net premiums earned also include premium adjustments related to the audit of our insureds' payrolls and changes in our estimates related to EBUB and premium adjustments related to retrospectively-rated policies. Payroll audits are conducted subsequent to the end of the policy period and any related premium adjustments processed are recorded as fully earned in the current period. We evaluate our estimates related to EBUB and retrospectively-rated premium adjustments on a quarterly basis with any adjustments being included in written and earned premium in the current period.

Net premiums earned were as follows:

Year Ended December 31
($ in thousands)20222021Change
Gross premiums earned$252,452$243,665$8,7873.6%
Less: Ceded premiums earned86,08179,0657,0168.9%
Net premiums earned$166,371$164,600$1,7711.1%

Net premiums earned increased during the year ended December 31, 2022 as compared to 2021 primarily reflecting higher audit premium and the change in the carried EBUB estimate, partially offset by the continuation of competitive market conditions.

Losses and Loss Adjustment Expenses

We estimate our current accident year loss and loss adjustment expenses by developing actual reported losses using historical loss development factors, adjusted to reflect current and expected trends based on various internal analyses and supplemental information. The following table summarizes calendar year net loss ratios by separating losses between the current accident year and all prior accident years. Calendar year and current accident year net loss ratios by component were as follows:

Year Ended December 31
20222021Change
Calendar year net loss ratio67.0%69.7%(2.7pts)
Less impact of prior accident years on the net loss ratio(4.8%)(4.3%)(0.5pts)
Current accident year net loss ratio71.8%74.0%(2.2pts)

The current accident year net loss ratio decreased in 2022 as compared to 2021 primarily reflecting an improvement in loss frequency and severity trends, partially offset by the continuation of intense price competition and the resulting renewal rate decreases. The current accident year net loss ratio in 2021 reflected higher claim activity as workers returned to employment with the easing of pandemic-related restrictions in our operating territories, including the impact of labor shortages on the existing workforce.

Calendar year incurred losses (excluding IBNR) in excess of our per occurrence reinsurance retention, before consideration of the AAD (see previous discussion under the heading "Ceded Premiums Written"), decreased $8.5 million in 2022 as compared to 2021. We retained losses in excess of our per occurrence retention totaling $5.0 million for the year ended December 31, 2022 as compared to $6.6 million in 2021 which reflected losses within the AAD.

We recognized net favorable prior year development of $8.0 million for the year ended December 31, 2022 as compared to $7.1 million for 2021. The net favorable prior year reserve development for the years ended December 31, 2022 and 2021 reflected overall favorable trends in claim closing patterns. Net favorable development for the year ended December 31, 2022 primarily related to accident years 2017 through 2020. Net favorable development for the year ended December 31, 2021 primarily related to accident years 2012 through 2017.

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Underwriting, Policy Acquisition and Operating Expenses

Underwriting, policy acquisition and operating expenses include the amortization of commissions, premium taxes and underwriting salaries, which are capitalized and deferred over the related workers’ compensation policy period, net of ceding commissions earned. The capitalization of underwriting salaries can vary as they are subject to the success rate of our contract acquisition efforts. These expenses also include a management fee charged by our Corporate segment, which represents intercompany charges pursuant to a management agreement, and the amortization of intangible assets, primarily related to the acquisition of Eastern by ProAssurance. The management fee is based on the extent to which services are provided to the subsidiary and the amount of premium written by the subsidiary.

Our Workers' Compensation Insurance segment underwriting, policy acquisition and operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20222021Change
DPAC amortization$29,585$29,092$4931.7%
Management fees1,8531,804492.7%
Other underwriting and operating expenses37,14634,3592,7878.1%
Policyholder dividend expense9021,155(253)(21.9%)
SPC ceding commission offset(14,749)(13,992)(757)5.4%
Total$54,737$52,418$2,3194.4%

The increase in DPAC amortization for the year ended December 31, 2022 as compared to 2021 primarily reflected the increase in gross premiums earned.

The increase in other underwriting and operating expenses for the year ended December 31, 2022 as compared to 2021 primarily reflected an increase in costs related to compensation and business-related travel as well as planned higher marketing costs related to advertising and website-related activities in 2022. The increase in compensation-related costs primarily reflected a higher headcount. The increase in travel-related costs reflected the easing of pandemic-related restrictions and the return to more normal business activity.

As previously discussed, alternative market premiums written by our Workers' Compensation Insurance segment are 100% ceded, less a ceding commission, to either the SPCs in our Segregated Portfolio Cell Reinsurance segment or unaffiliated captive insurers. The ceding commission charged to the SPCs consists of an amount for fronting fees, cell rental fees, commissions, premium taxes, claims administration fees and risk management fees. The fronting fees, commissions, premium taxes and risk management fees are recorded as an offset to underwriting, policy acquisition and operating expenses. Cell rental fees are recorded as a component of other income and claims administration fees are recorded as ceded ULAE. The increase in SPC ceding commissions earned for the year ended December 31, 2022 as compared to 2021, primarily reflected the increase in alternative market ceded earned premium.

Underwriting Expense Ratio (the Expense Ratio)

The underwriting expense ratio included the impact of the following:

Year Ended December 31
20222021Change
Underwriting expense ratio, as reported32.9%31.8%1.1pts
Less estimated ratio increase (decrease) attributable to:
Impact of ceding commissions received from SPCs3.9%3.3%0.6pts
Impact of audit premium(1.2%)0.4%(1.6pts)
Underwriting expense ratio, less listed effects30.2%28.1%2.1pts

Excluding the items noted in the table above, the expense ratio increased for the year ended December 31, 2022, primarily reflecting the increase in other underwriting and operating expenses, as previously discussed.

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Segment Results - Segregated Portfolio Cell Reinsurance

The Segregated Portfolio Cell Reinsurance segment includes the results (underwriting profit or loss, plus investment results, net of U.S. federal income taxes) of SPCs at Inova Re and Eastern Re, our Cayman Islands SPC operations, as discussed in Note 17 of the Notes to Consolidated Financial Statements. SPCs are segregated pools of assets and liabilities that provide an insurance facility for a defined set of risks. Assets of each SPC are solely for the benefit of that individual cell and each SPC is solely responsible for the liabilities of that individual cell. Assets of one SPC are statutorily protected from the creditors of the others. Each SPC is owned, fully or in part, by an individual company, agency, group or association and the results of the SPCs are attributable to the participants of that cell. We participate to a varying degree in the results of selected SPCs and, for the SPCs in which we participate, our participation interest ranges from a low of 15% to a high of 85%. SPC results attributable to external cell participants are reported as an SPC dividend (expense) income in our Segregated Portfolio Cell Reinsurance segment. In addition, our Segregated Portfolio Cell Reinsurance segment includes the investment results of the SPCs as the investments are solely for the benefit of the cell participants and investment results attributable to external cell participants are reflected in the SPC dividend (expense) income. As of December 31, 2022, there were 27 (4 inactive) SPCs. The SPCs assume workers' compensation insurance, healthcare professional liability insurance or a combination of the two from our Workers' Compensation Insurance and Specialty P&C segments. As of December 31, 2022, there were two SPCs that assumed both workers' compensation insurance and healthcare professional liability insurance and one SPC that assumed only healthcare professional liability insurance.

Segment results reflects our share of the underwriting and investment results of the SPCs in which we participate, and included the following:

Year Ended December 31
($ in thousands)20222021Change
Net premiums written$69,357$63,042$6,31510.0%
Net premiums earned$69,810$63,688$6,1229.6%
Net investment income1,02981421526.4%
Net investment gains (losses)(3,067)4,080(7,147)(175.2%)
Other income23(1)(33.3%)
Net losses and loss adjustment expenses(39,310)(32,569)(6,741)20.7%
Underwriting, policy acquisition and operating expenses(20,316)(21,635)1,319(6.1%)
SPC U.S. federal income tax expense (1)(1,759)(1,947)188(9.7%)
SPC net results6,38912,434(6,045)(48.6%)
SPC dividend (expense) income (2)(6,673)(10,050)3,377(33.6%)
Segment results (3)$(284)$2,384$(2,668)(111.9%)
Net loss ratio56.3%51.1%5.2 pts
Underwriting expense ratio29.1%34.0%(4.9 pts)
(1) Represents the provision for U.S. federal income taxes for SPCs at Inova Re, which have elected to be taxed as a U.S. corporation under Section 953(d) of the Internal Revenue Code. U.S. federal income taxes are included in the total SPC net results and are paid by the individual SPCs.
(2) Represents the net (profit) loss attributable to external cell participants.
(3) Represents our share of the net profit (loss) and OCI of the SPCs in which we participate.

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Premiums Written

Premiums in our Segregated Portfolio Cell Reinsurance segment are assumed from either our Workers' Compensation Insurance or Specialty P&C segments. Premium volume is driven by five primary factors: (1) the amount of new business written, (2) retention of the existing book of business, (3) premium rates charged on the renewal book of business and, for workers' compensation business, (4) changes in payroll exposure and (5) audit premium.

Gross, ceded and net premiums written were as follows:

Year Ended December 31
($ in thousands)20222021Change
Gross premiums written$78,937$71,850$7,0879.9%
Less: Ceded premiums written9,5808,8087728.8%
Net premiums written$69,357$63,042$6,31510.0%

Gross Premiums Written

Gross premiums written reflected reinsurance premiums assumed by component as follows:

Year Ended December 31
($ in thousands)20222021Change
Workers' compensation$68,035$64,639$3,3965.3%
Healthcare professional liability10,9027,2113,69151.2%
Gross Premiums Written$78,937$71,850$7,0879.9%

Gross premiums written for the years ended December 31, 2022 and 2021 were primarily comprised of workers' compensation coverages assumed from our Workers' Compensation Insurance segment. Workers' compensation gross premiums written increased during the year ended December 31, 2022 as compared to 2021 reflecting higher audit premium, partially offset by a decrease in renewal premium. The increase in healthcare professional liability gross premiums written in 2022 as compared to 2021 primarily reflected the impact of tail coverage premium related to one program in which we do not participate. See further discussion in our Segment Results - Specialty Property & Casualty section under the heading "Premiums Written." We retained 100% of the twenty-two workers' compensation and three healthcare professional liability alternative market programs up for renewal for the year ended December 31, 2022.

New business, audit premium, retention and renewal price changes for the assumed workers' compensation premium is shown in the table below:

Year Ended December 31
($ in millions)20222021
New business$3.6$3.3
Audit premium$5.4$1.1
Retention rate (1)87%89%
Change in renewal pricing (2)(4%)(4%)
(1) We calculate our workers' compensation retention rate as annualized expiring renewed premium divided by all annualized expiring premium subject to renewal. Our retention rate can be impacted by various factors, including price or other competitive issues, insureds being acquired, or a decision not to renew based on our underwriting evaluation.
(2) The pricing of our business includes an assessment of the underlying policy exposure and market conditions. We continue to base our pricing on expected losses, as indicated by our historical loss data.

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Ceded Premiums Written

Ceded premiums written were as follows:

Year Ended December 31
($ in thousands)20222021Change
Ceded premiums written$9,580$8,808$7728.8%

For the workers' compensation business, each SPC has in place its own external reinsurance coverage. The healthcare professional liability business is assumed net of reinsurance from our Specialty P&C segment; therefore, there are no ceded premiums related to the healthcare professional liability business reflected in the table above. The risk retention for each loss occurrence for the workers' compensation business ranges from $0.3 million to $0.4 million based on the program, with limits up to $119.7 million. In addition, each program has aggregate reinsurance coverage between $1.1 million and $2.1 million on a program year basis. Premiums ceded under our SPC reinsurance treaty are based on premiums written during the treaty period. The change in ceded premiums written in 2022 as compared to 2021 primarily reflected the increase in workers' compensation gross premiums written and the impact of rate increases under the external reinsurance treaty. External reinsurance rates vary based on the alternative market program.

Ceded Premiums Ratio

Ceded premiums ratio was as follows:

Year Ended December 31
20222021Change
Ceded premiums ratio14.1%13.6%0.5pts

The above table reflects ceded premiums as a percent of gross premiums written for the workers' compensation business only; healthcare professional liability business is assumed net of reinsurance, as discussed above. The ceded premiums ratio reflects the weighted average reinsurance rates of all SPC programs. The increase in the ceded premiums ratio for the year ended December 31, 2022 reflects an increase in reinsurance rates.

Net Premiums Earned

Net premiums earned consist of gross premiums earned less the portion of earned premiums that the SPCs cede to external reinsurers. Because premiums are generally earned pro rata over the entire policy period, fluctuations in premiums earned tend to lag those of premiums written. Policies ceded to the SPCs are twelve month term policies and premiums are earned on a pro rata basis over the policy period. Net premiums earned also include premium adjustments related to the audit of workers' compensation insureds' payrolls. Payroll audits are conducted subsequent to the end of the policy period and any related adjustments are recorded as fully earned in the current period.

Gross, ceded and net premiums earned were as follows:

Year Ended December 31
($ in thousands)20222021Change
Gross premiums earned$79,347$72,359$6,9889.7%
Less: Ceded premiums earned9,5378,67186610.0%
Net premiums earned$69,810$63,688$6,1229.6%

The increase in net premiums earned during the year ended December 31, 2022 as compared to 2021, primarily reflected the aforementioned impact of healthcare professional liability tail premium written and fully earned and the increase in workers' compensation audit premium billed to policyholders.

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Losses and Loss Adjustment Expenses

The following table summarizes the calendar year net loss ratios by separating losses between the current accident year and all prior accident years. The current accident year net loss ratio reflects the aggregate loss ratio for all programs. Loss reserves and associated reinsurance are estimated for each program on a quarterly basis. Each SPC has in place its own reinsurance agreement, and the attachment point of aggregate reinsurance coverage varies by program. Due to the size of some of the programs, quarterly loss results, including changes in estimated aggregate reinsurance, can create volatility in the current accident year net loss ratio from period to period.

Calendar year and current accident year net loss ratios for the years ended December 31, 2022 and 2021 were as follows:

Year Ended December 31
20222021Change
Calendar year net loss ratio56.3%51.1%5.2pts
Less impact of prior accident years on the net loss ratio(9.0%)(16.0%)7.0pts
Current accident year net loss ratio65.3%67.1%(1.8pts)
Less estimated ratio increase (decrease) attributable to:
Change in estimated aggregate reinsurance0.9%(2.2%)3.1pts
Current accident year net loss ratio, excluding the effect of the change in estimated aggregate reinsurance64.4%69.3%(4.9pts)

During the year ended December 31, 2022, we decreased our estimate of aggregate reinsurance which increased our current accident year net loss ratios as compared to 2021. The decrease in the estimated aggregate reinsurance reflected an improvement in expected ultimate program year losses in certain programs. See additional information regarding the SPC's aggregate reinsurance agreements in our Liquidity section under the heading "Operating Activities and Related Cash Flows."

The current accident year net loss ratio, excluding the effect of changes in estimated aggregate reinsurance, decreased in 2022 as compared to 2021, reflecting a lower workers' compensation current accident year net loss ratio, partially offset by a higher healthcare professional liability current accident year net loss ratio. The improvement in the workers' compensation current accident year net loss ratio for 2022 primarily reflects favorable trends in prior accident year workers' compensation claim results and their impact on our analysis of the current year loss estimate, and the impact of audit premium, partially offset by the continuation of intense price competition and the resulting renewal rate decreases in the workers' compensation business. The increase in the healthcare professional liability current accident year loss ratio for 2022 primarily reflected an increase in expected claim frequency related to one program in which we do not participate.

Calendar year incurred losses (excluding IBNR) ceded to our external reinsurers increased $2.9 million for the year ended December 31, 2022 as compared to 2021. Current accident year ceded incurred losses (excluding IBNR) increased $5.1 million for the year ended December 31, 2022 as compared to 2021.

We recognized net favorable prior year reserve development of $6.3 million and $10.2 million for the years ended December 31, 2022 and 2021, respectively.

Net favorable prior year reserve development in the workers' compensation business totaled $7.0 million in 2022 as compared to $7.6 million in 2021. The 2022 net favorable prior year reserve development in the workers' compensation business reflected overall favorable trends in claim closing patterns primarily in accident years 2016 through 2021. The 2021 net favorable development related primarily to accident year 2015 and accident years 2018 through 2020.

Net unfavorable prior year reserve development in the healthcare professional liability business totaled $0.7 million in 2022 as compared to $2.5 million of favorable development in 2021. The 2022 net unfavorable prior year reserve development primarily reflected higher than expected claim frequency in one program in which we do not participate. The 2021 net favorable prior year reserve development related primarily to accident years 2018 through 2020.

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Underwriting, Policy Acquisition and Operating Expenses

Our Segregated Portfolio Cell Reinsurance segment underwriting, policy acquisition and operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20222021Change
DPAC amortization$20,068$18,730$1,3387.1%
Policyholder dividend expense167508(341)(67.1%)
Other underwriting and operating expenses812,397(2,316)(96.6%)
Total$20,316$21,635$(1,319)(6.1%)

DPAC amortization primarily represents ceding commissions, which vary by program and are paid to our Workers' Compensation Insurance and Specialty P&C segments for premiums assumed. Ceding commissions include an amount for fronting fees, commissions, premium taxes and risk management fees, which are reported as an offset to underwriting, policy acquisition and operating expenses within our Workers' Compensation Insurance and Specialty P&C segments. In addition, ceding commissions paid to our Workers' Compensation Insurance segment include cell rental fees which are recorded as other income and claims administration fees which are recorded as ceded ULAE within our Workers' Compensation Insurance segment.

Other underwriting and operating expenses primarily include bank fees, professional fees and changes in the allowance for expected credit losses. The decrease in other underwriting and operating expenses for the year ended December 31, 2022 as compared to 2021 primarily reflects changes in the allowance for expected credit losses related to the collection of customer accounts that were previously written off.

The decrease in policyholder dividend expense for the year ended December 31, 2022 as compared to 2021, primarily reflects changes in estimated dividends for one SPC program, in which we do not participate.

Underwriting Expense Ratio (the Expense Ratio)

The underwriting expense ratio included the impact of the following:

Year Ended December 31
20222021Change
Underwriting expense ratio, as reported29.1%34.0%(4.9pts)
Less: impact of audit premium on expense ratio(2.3%)(0.5%)(1.8pts)
Underwriting expense ratio, excluding the effect of audit premium31.4%34.5%(3.1pts)

Excluding the effect of audit premium, the underwriting expense ratio decreased for the year ended December 31, 2022. The decrease in the underwriting expense ratio in 2022 primarily reflected the change in the allowance for expected credit losses and policyholder dividend expense, as discussed above.

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Segment Results - Lloyd's Syndicates

Our Lloyd's Syndicates segment includes the results from our participation in Syndicate 1729 and Syndicate 6131 at Lloyd's of London. In addition to our participation in Syndicate results, we have investments in and other obligations to our Lloyd's Syndicates consisting of a Syndicate Credit Agreement and FAL requirements. For the 2022 underwriting year, our FAL was comprised of investment securities and cash and cash equivalents deposited with Lloyd's which at December 31, 2022 had a fair value of approximately $24.8 million, as discussed in Note 4 of the Notes to Consolidated Financial Statements. During the second quarter of 2022 we received a return of approximately $5.5 million of cash from our FAL balances given Syndicate 6131 ceased underwriting on a quota share basis with Syndicate 1729 as Syndicate 6131's business is retained within Syndicate 1729 beginning with the 2022 underwriting year. The return of FAL during the second quarter of 2022 also related to the settlement of our participation in the results of Syndicate 1729 and Syndicate 6131 for the 2019 underwriting year. Further, during the fourth quarter of 2022, we received a return of approximately $5.6 million of cash from our FAL balances due to lower capital requirements for the 2023 underwriting year following Lloyd's of London's review of Syndicate 1729's 2023 business plan.

We normally report results from our involvement in Lloyd's Syndicates on a quarter lag, except when information is available that is material to the current period. Furthermore, the investment results associated with our FAL investments and certain U.S. paid administrative expenses are reported concurrently as that information is available on an earlier time frame.

We provide capital to Syndicate 1729, which covers a range of property and casualty insurance and reinsurance lines in both the U.S. and international markets. The remaining capital for Syndicate 1729 is provided by unrelated third parties, including private names and other corporate members. For each of the 2023 and 2022 underwriting years our participation in the results of Syndicate 1729 is approximately 5%. Syndicate 1729 had a maximum underwriting capacity of £210 million (approximately $254 million at December 31, 2022) for the 2022 underwriting year, of which £11 million (approximately $14 million at December 31, 2022) is our allocated underwriting capacity. Effective January 1, 2022, Syndicate 6131 ceased underwriting on a quota share basis with Syndicate 1729, as previously discussed; the results from our participation in Syndicate 6131 from open underwriting years prior to 2022 will continue to earn out pro rata over the entire policy period of the underlying business. Due to the quarter lag, our ceased participation in Syndicate 6131 was not reflected in our results until the second quarter of 2022. Syndicate 1729's maximum underwriting capacity for the 2023 underwriting year is £280 million (approximately $338 million at December 31, 2022), of which £15 million (approximately $18 million at December 31, 2022) is our allocated underwriting capacity.

In addition to the results of our participation in Lloyd's Syndicates, as discussed above, our Lloyd's Syndicates segment also includes 100% of the results of our wholly owned subsidiaries that support our operations at Lloyd's. For the years ended December 31, 2022 and 2021, the results of our Lloyd's Syndicates segment were as follows:

Year Ended December 31
($ in thousands)20222021Change
Gross premiums written$20,233$37,969$(17,736)(46.7%)
Less: Ceded premiums written(1,657)(6,302)4,645(73.7%)
Net premiums written$18,576$31,667$(13,091)(41.3%)
Net premiums earned$23,627$48,372$(24,745)(51.2%)
Net investment income5681,961(1,393)(71.0%)
Net investment gains (losses)(964)249(1,213)(487.1%)
Other income119912(793)(87.0%)
Net losses and loss adjustment expenses(16,130)(29,812)13,682(45.9%)
Underwriting, policy acquisition and operating expenses(7,412)(17,957)10,545(58.7%)
Segment results$(192)$3,725$(3,917)(105.2%)
Net loss ratio68.3%61.6%6.7 pts
Underwriting expense ratio31.4%37.1%(5.7 pts)

Premiums

Changes in premium volume within our Lloyd's Syndicates segment are driven by five primary factors: (1) changes in our participation in the Syndicates, (2) the amount of new business and the channels in which the business is written, (3) the retention of existing business, (4) the premium charged for business that is renewed, which is affected by rates charged and by the amount and type of coverage an insured chooses to purchase and (5) the timing of premium written through multi-period policies. Gross premiums written in 2022 consisted of property insurance coverages (30% of total gross premiums written), casualty coverages (24%), catastrophe reinsurance coverages (16%), contingency coverages (14%), specialty property

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coverages (13%) and property reinsurance coverages (3%). The decrease in net premiums written in 2022 as compared to 2021 was primarily driven by the impact of our decreased participation in the results of Syndicates 1729 and 6131 for the 2021 underwriting year and our ceased participation in Syndicate 6131 for the 2022 underwriting year. The decrease in net premiums written in 2022 was partially offset by volume increases on renewal business and renewal pricing increases, primarily on property and specialty insurance coverages, as well as new business written, primarily on property insurance and casualty coverages.

Net premiums earned consist of gross premiums earned less the portion of earned premiums that the Syndicates cede to reinsurers for their assumption of a portion of losses. Premiums written through open-market channels are generally earned pro rata over the entire policy period, which is predominantly twelve months, whereas premiums written through delegated underwriting authority arrangements are generally earned over the policy period plus twelve months. Therefore, net premiums earned is affected by shifts in the mix of policies written between the open-market and delegated underwriting authority arrangements. Additionally, net premiums earned consists of a mix of policies earned from different open underwriting years. As previously discussed, we participate to a varying degree in each open underwriting year which may cause fluctuations in premiums earned. Furthermore, fluctuations in premiums earned tend to lag those of premiums written. Premiums for certain policies and assumed reinsurance contracts are reported subsequent to the coverage period and/or may be subject to adjustment based on loss experience. These premium adjustments are earned when reported, which can result in further fluctuation in earned premium. Net premiums earned decreased during the year ended December 31, 2022 as compared to 2021 primarily attributable to the pro rata effect of a reduction in net premiums written during the preceding twelve months.

Net Losses and Loss Adjustment Expenses

Losses for the year were primarily recorded using the loss assumptions by risk category incorporated into the business plan submitted to Lloyd's for Syndicate 1729 with consideration given to loss experience incurred to date. The assumptions used in the business plan were consistent with loss results reflected in Lloyd's historical data for similar risks. The loss ratios may fluctuate due to the mix of earned premium and the timing of earned premium adjustments (see discussion in this section under the heading "Premiums"). Premium and exposure for some of Syndicate 1729's insurance policies and reinsurance contracts are initially estimated and subsequently adjusted over an extended period of time as underlying premium reports are received from cedents and insureds. When reports are received, the premium, exposure and corresponding loss estimates are revised accordingly. Changes in loss estimates due to premium or exposure fluctuations are incurred in the accident year in which the premium is earned.

The following table summarizes calendar year net loss ratios by separating losses between the current accident year and all prior accident years. Net loss ratios for the period were as follows:

Year Ended December 31
20222021Change
Calendar year net loss ratio68.3%61.6%6.7pts
Less: impact of prior accident years on the net loss ratio31.1%9.7%21.4pts
Current accident year net loss ratio37.2%51.9%(14.7pts)

The current accident year net loss ratio decreased in 2022 as compared to 2021 driven by decreases to certain loss estimates during the first quarter of 2022, partially offset by lower reinsurance recoveries as a proportion of gross losses as compared to the prior year period and, to a lesser extent, certain catastrophe losses in the current period.

We recognized $7.3 million and $4.7 million of unfavorable prior year development for the years ended December 31, 2022 and 2021, respectively. The unfavorable prior year development for the year ended December 31, 2022 was driven by higher than expected losses and development on certain large claims, primarily catastrophe related losses.

Underwriting, Policy Acquisition and Operating Expenses

For the year ended December 31, 2022, the underwriting expense ratio decreased by 5.7 percentage points as compared to 2021, which primarily reflected the impact of our ceased participation in Syndicate 6131 for the 2022 underwriting year. Syndicate 6131 incurred nominal operating expenses during 2022, whereas the net premiums earned during the same period also includes premium from open underwriting years prior to 2022. The decrease in the underwriting expense ratio in 2022 also reflected the impact of our reduced participation in the results of Syndicate 1729 and Syndicate 6131 for the 2021 underwriting year.

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Segment Results - Corporate

Our Corporate segment includes our investment operations excluding those reported in our Segregated Portfolio Cell Reinsurance and Lloyd's Syndicates segments as discussed in Note 16 of the Notes to Consolidated Financial Statements. In addition, this segment includes corporate expenses, interest expense, U.S. income taxes and non-premium revenues generated outside of our insurance entities. Segment results for the year ended December 31, 2022 and 2021 exclude transaction-related costs as well as the associated income tax benefit and, for 2022, the change in fair value of contingent consideration related to the NORCAL acquisition as we do not consider these items in assessing the financial performance of the segment. For additional information on the NORCAL acquisition see Note 2 of the Notes to Consolidated Financial Statements. Segment results for our Corporate segment were net earnings of $17.7 million and $91.2 million for the years ended December 31, 2022 and 2021, respectively, and included the following:

Year Ended December 31
($ in thousands)20222021Change
Net investment income$94,375$67,747$26,62839.3%
Equity in earnings (loss) of unconsolidated subsidiaries$4,888$48,974$(44,086)(90.0%)
Net investment gains (losses)$(38,126)$19,981$(58,107)(290.8%)
Other income$6,198$5,531$66712.1%
Operating expense$34,733$26,641$8,09230.4%
Interest expense$20,372$19,719$6533.3%
Income tax expense (benefit)$(5,423)$4,651$(10,074)(216.6%)

Net Investment Income, Equity in Earnings (Loss) of Unconsolidated Subsidiaries, Net Investment Gains (Losses)

Net Investment Income

Net investment income is primarily derived from the income earned by our fixed maturity securities and also includes dividend income from equity securities, income from our short-term and cash equivalent investments, earnings from other investments and increases in the cash surrender value of BOLI contracts, net of investment fees and expenses.

Net investment income (loss) by investment category was as follows:

Year Ended December 31
($ in thousands)20222021Change
Fixed maturities$92,034$71,451$20,58328.8%
Equities3,7062,5391,16746.0%
Short-term investments, including Other5,4141,8603,554191.1%
BOLI1,1412,699(1,558)(57.7%)
Investment fees and expenses(7,920)(10,802)2,882(26.7%)
Net investment income$94,375$67,747$26,62839.3%

Fixed Maturities

Income from our fixed maturities increased in 2022 as compared to 2021 driven by higher average book yields as we continue to reinvest at higher rates as our portfolio matures. In addition, the increase in income from our fixed maturities during 2022 reflected higher average investment balances primarily attributable to the addition of fixed maturity securities valued at $1.1 billion to our portfolio on May 5, 2021 as a result of the NORCAL acquisition. As a result of the NORCAL acquisition, average investment balances over a twelve month period were approximately 17% higher for 2022 as compared to 2021; excluding the impact of the acquisition, average investment balances were approximately 2% higher.

Average yields for our fixed maturity portfolio were as follows:

Year Ended December 31
20222021
Average income yield2.5%2.3%
Average tax equivalent income yield2.5%2.3%

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Equities

Income from our equity portfolio increased in 2022 as compared to 2021 which reflected changes in the mix of equities owned.

Short-term Investments and Other Investments

Short-term investments, which have a maturity at purchase of one year or less are carried at fair value, which approximates their cost basis, and are primarily composed of investments in U.S. treasury obligations, commercial paper and money market funds. Income from our short-term and other investments increased during 2022 primarily due to higher yields given the increase in interest rates.

BOLI

We hold BOLI policies that are carried at the current cash surrender value of the policies, which includes the BOLI policies acquired from NORCAL. All insured individuals were members of ProAssurance or NORCAL management at the time the policies were acquired. Income from our BOLI policies decreased in 2022 as compared to 2021 primarily attributable to a decrease in the cash surrender value of policies acquired from NORCAL.

Investment Fees and Expenses

Investment fees and expenses decreased in 2022 as compared to 2021 primarily due to no longer paying an incentive fee on convertibles and the renegotiation of our contract due to the addition of NORCAL.

Equity in Earnings (Loss) of Unconsolidated Subsidiaries

Equity in earnings (loss) of unconsolidated subsidiaries was comprised as follows:

Year Ended December 31
($ in thousands)20222021Change
All other investments, primarily investment fund LPs/LLCs$11,954$64,031$(52,077)(81.3%)
Tax credit partnerships(7,066)(15,057)7,991(53.1%)
Equity in earnings (loss) of unconsolidated subsidiaries$4,888$48,974$(44,086)(90.0%)

We hold interests in certain LPs/LLCs that generate earnings from trading portfolios, secured debt, debt securities, multi-strategy funds and private equity investments. The performance of the LPs/LLCs is affected by the volatility of equity and credit markets. For our investments in LPs/LLCs, we record our allocable portion of the partnership operating income or loss as the results of the LPs/LLCs become available, typically following the end of a reporting period. Our investment results from our portfolio of investments in LPs/LLCs for 2022 as compared to 2021 decreased primarily due to the performance of certain LP/LLCs which reflected lower market valuations during 2022.

Our tax credit partnership investments are designed to generate returns in the form of tax credits and tax-deductible project operating losses and are comprised of qualified affordable housing project tax credit partnerships and a historic tax credit partnership. We account for our tax credit partnership investments under the equity method and record our allocable portion of the operating losses of the underlying properties based on estimates provided by the partnerships. For our qualified affordable housing project tax credit partnerships, we adjust our estimates of our allocable portion of operating losses periodically as actual operating results of the underlying properties become available. The primary benefit of credits and losses from our historic tax credit partnership are earned in a short period with potential for additional cash flows extending over several years. The results from our tax credit partnership investments for the year ended December 31, 2022 reflected lower partnership operating losses as compared to 2021, partially offset by an increase in our estimate of operating losses by $1.0 million and $1.9 million for the years ended December 31, 2022 and 2021, respectively.

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The tax benefits received from our tax credit partnerships, which are not reflected in our investment results, reduced our tax expense in 2022 and 2021 as follows:

Year Ended December 31
(In millions)20222021
Tax credits recognized during the period$4.8$13.2
Tax benefit of tax credit partnership operating losses$1.5$3.2

The tax credits generated from our tax credit partnership investments of $4.8 million for 2022 were deferred for use in future periods due to our expected consolidated loss calculated on a tax basis. For the year ended December 31, 2021, the tax credits generated from our tax credit partnership investments of $13.2 million were deferred to be utilized in future periods. Not included in the table above is $0.5 million of tax credits recaptured from the 2019 tax year during the year ended December 31, 2022 due to the carryback of our estimated NOL for the year ended December 31, 2022 to the 2021 tax year. The recaptured tax credits were earned in 2019 but not utilized until 2021 due to NOL's generated in both 2019 and 2020. As of December 31, 2022, we had approximately $51.2 million of available tax credit carryforwards generated from our investments in tax credit partnerships which we expect to utilize in future years. See further discussion in Note 6 of the Notes to Consolidated Financial Statements.

Tax credits provided by the underlying projects of our historic tax credit partnership are typically available in the tax year in which the project is put into active service, whereas the tax credits provided by qualified affordable housing project tax credit partnerships are provided over approximately a ten year period.

Net Investment Gains (Losses)

The following table provides detailed information regarding our net investment gains (losses).

Year Ended December 31
(In thousands)20222021
Total impairment losses
Corporate debt$(1,331)$
Asset-backed securities(441)
Portion of impairment losses recognized in other comprehensive income before taxes:
Asset-backed securities14
Net impairment losses recognized in earnings(1,758)
Gross realized gains, available-for-sale fixed maturities1,64913,047
Gross realized (losses), available-for-sale fixed maturities(3,041)(1,133)
Net realized gains (losses), equity investments(5,928)5,394
Net realized gains (losses), other investments(222)8,660
Change in unrealized holding gains (losses), equity investments(18,483)(4,697)
Change in unrealized holding gains (losses), convertible securities, carried at fair value as a part of other investments(10,557)(1,701)
Other214411
Net investment gains (losses)$(38,126)$19,981

For the year ended December 31, 2022, we recognized $1.8 million of credit-related impairment losses in earnings and a nominal amount of non-credit impairment losses in OCI. The credit-related impairment losses recognized during the year ended December 31, 2022 related to a corporate bond in the consumer sector as well as certain mortgage-backed and other asset-backed securities. We did not recognize any credit-related impairment losses in earnings or non-credit impairment losses in OCI for the year ended December 31, 2021.

We recognized $38.1 million of net investment losses for the year ended December 31, 2022 driven by unrealized holding losses resulting from changes in the fair value of our equity investments and convertible securities and, to a lesser extent, realized losses from the sale of equity investments. We recognized $20.0 million of net investment gains for the year ended December 31, 2021, driven primarily by realized gains on the sale of certain available-for-sale fixed maturities and other investments, partially offset by unrealized holding losses resulting from decreases in the fair value on our equity portfolio.

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Operating Expenses

Corporate segment operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20222021Change
Operating expenses$41,350$36,007$5,34314.8%
Management fee offset(6,617)(9,366)2,749(29.4%)
Total$34,733$26,641$8,09230.4%

Operating expenses increased during the year ended December 31, 2022 as compared to 2021 primarily due to an increase in compensation-related costs, professional fees, business-related travel and share-based compensation expenses. The increase in professional fees in 2022 was primarily driven by an increase in consulting fees and, to a lesser extent, an increase in recruiting and employee placement fees as a result of filling open positions across the organization. Prior to 2022, recruiting and employee placement fees were allocated to the operating segments. The increase in compensation-related costs during 2022 was driven by an increase in segment headcount due to the addition of Corporate NORCAL employees. Subsequent to acquisition on May 5, 2021, compensation-related costs of all NORCAL employees were reported in our Specialty P&C segment. Beginning in 2022, compensation-related costs for Corporate NORCAL employees are reported in our Corporate segment. In addition, the increase in compensation-related costs also reflected higher amounts accrued for performance-related incentive plans due to our improved performance metrics. The increase in share-based compensation expenses in 2022 was attributable to the effect of the incorporation of certain NORCAL employees into our share-based compensation plans beginning in 2022.

Operating subsidiaries within our Specialty P&C segment and our Workers' Compensation Insurance segment are charged a management fee by the Corporate segment for services provided to these subsidiaries. The management fee is based on the extent to which services are provided to the subsidiary and the amount of premium written by the subsidiary. Under the arrangement, the expenses associated with such services are reported as expenses of the Corporate segment, and the management fees charged are reported as an offset to Corporate operating expenses. Fluctuations in the amount of premium written by each subsidiary can result in corresponding variations in the management fee charged to each subsidiary during a particular period. Due to continued organizational structure enhancements in our Specialty P&C segment during 2021 as well as operational alignments as a result of the integration of NORCAL, the extent to which services are provided exclusively by the Corporate segment to the operating subsidiaries within the Specialty P&C segment decreased further effective January 1, 2022. Accordingly, we reduced the fee charged to the operating subsidiaries within the Specialty P&C segment during the first quarter of 2022. Also effective January 1, 2022, the management agreement included the wholly owned operating subsidiaries of NORCAL contributing to $1.3 million of additional management fees during 2022. There were no changes to the extent to which services are provided exclusively by the Corporate segment to the operating subsidiaries within our Workers' Compensation Insurance segment in 2022.

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Interest Expense

Consolidated interest expense for the years ended December 31, 2022 and 2021 was comprised as follows:

Year Ended December 31
($ in thousands)20222021Change
Senior Notes due 2023$13,429$13,429$%
Contribution Certificates (including accretion)(1)7,3325,0462,28645.3%
Revolving Credit Agreement (including fees and amortization) (2)1,0161,120(104)(9.3%)
Mortgage Loans (including amortization)444(444)nm
(Gain)/loss on interest rate cap(1,405)(320)(1,085)(339.1%)
Interest expense$20,372$19,719$6533.3%
(1) Includes accretion of approximately $1.8 million and $1.2 million for the years ended December 31, 2022 and 2021, respectively, which is recorded as an increase to interest expense as a result of the difference between the recorded acquisition date fair value and the principal balance of the Contribution Certificates associated with our acquisition of NORCAL.
(2) There were no outstanding borrowings on our Revolving Credit Agreement during the year ended December 31, 2022. During the third quarter of 2021, we repaid the balance outstanding on the Revolving Credit Agreement of $15.0 million. Interest expense in both 2022 and 2021 primarily reflected unused commitment fees.

Consolidated interest expense increased during 2022 as compared to 2021 driven by the Contribution Certificates associated with our acquisition of NORCAL on May 5, 2021 (see Note 2 and Note 11 of the Notes to Consolidated Financial Statements), partially offset by the change in the fair value of our interest rate cap which was terminated in the second quarter of 2022. See further discussion of our interest rate cap agreement in Note 3 and further discussion on our outstanding debt in Note 11 of the Notes to Consolidated Financial Statements.

Taxes

Tax expense allocated to our Corporate segment includes U.S. tax only, which would include U.S. tax expense incurred from our corporate membership in Lloyd's of London. Any U.K. tax expense incurred by the U.K. based subsidiaries of our Lloyd's Syndicates segment is allocated to that segment. The SPCs at Inova Re, one of our Cayman Islands reinsurance subsidiaries, have each made a 953(d) election under the U.S. Internal Revenue Code and are subject to U.S. federal income tax; therefore, tax expense allocated to our Corporate segment also includes tax expense incurred from any SPC at Inova Re in which we have a participation interest of 80% or greater as those SPCs are required to be included in our consolidated tax return. Consolidated tax expense (benefit) reflects the tax expense (benefit) of both segments and the tax impact of items excluded from segment reporting, as shown in the table below:

Year Ended December 31
(In thousands)20222021
Corporate segment income tax expense (benefit)$(5,423)$4,651
Income tax expense (benefit) - transaction-related costs*(391)(2,168)
Consolidated income tax expense (benefit)$(5,814)$2,483
*Represents the income tax benefit associated with the transaction-related costs related to our acquisition of NORCAL that are not included in a segment as we do not consider these costs in assessing the financial performance of any of our operating or reportable segments. See Note 16 of the Notes to Consolidated Financial Statements for a reconciliation of our segment results to our consolidated results.

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Listed below are the primary factors affecting our consolidated effective tax rate for the years ended December 31, 2022 and 2021. The comparability of each factor's impact on our effective tax rate is affected by the consolidated pre-tax loss recognized during 2022 as compared to the consolidated pre-tax income recognized during 2021. Factors that have the same directional impact on income tax expense (benefit) in each period have an opposite impact on our effective tax rate due to the effective tax rate being calculated based upon a pre-tax loss during the year ended December 31, 2022 versus the pre-tax income during the year ended December 31, 2021. These factors include the following:

Year Ended December 31
20222021
($ in thousands)Income tax (benefit) expenseRate ImpactIncome tax (benefit) expenseRate Impact
Computed "expected" tax expense (benefit) at statutory rate$(1,305)21.0%$30,78721.0%
Tax-exempt income (1)(1,072)17.2%(1,298)(0.9%)
Tax credits(4,805)77.3%(13,160)(9.0%)
Non-U.S. operating results(411)6.6%(1,322)(0.9%)
Tax deficiency (excess tax benefit) on share-based compensation309(5.0%)2860.2%
Non-taxable gain on bargain purchase (2)%(15,626)(10.7%)
Non-taxable contingent consideration(3)(1,890)30.4%%
Provision-to-return and other differences1,112(17.9%)3,5742.4%
Change in uncertain tax positions780(12.5%)(1,909)(1.3%)
Change in limitation of future deductibility of certain executive compensation708(11.4%)3030.3%
GILTI and subpart F income556(8.9%)7210.6%
State income taxes105(1.7%)4600.3%
Other99(1.6%)(333)(0.3%)
Total income tax expense (benefit)$(5,814)93.5%$2,4831.7%

(1) Includes tax-exempt interest, dividends received deduction and change in cash surrender value of BOLI.

(2) Represents the tax impact of the non-taxable gain on bargain purchase as a result of our acquisition of NORCAL on May 5, 2021. See further discussion on the gain on bargain purchase in Note 2 of the Notes to Consolidated Financial Statements.

(3) Represents the tax impact of the change in the fair value of contingent consideration issued in connection with the NORCAL acquisition, all of which is non-taxable. See further discussion on the contingent consideration in Note 2 and Note 3 of the Notes to Consolidated Financial Statements.

Our consolidated effective tax rates for 2022 and 2021, as shown in the table above, differed from the statutory federal income tax rate of 21% in each respective year typically due to the benefit recognized from the tax credits transferred to us from our tax credit partnership investments. Tax credits recognized for the year ended December 31, 2022 were $4.8 million as compared to $13.2 million in 2021. While projected tax credits for 2022 are less than 2021, they continue to have a significant impact on the effective tax rate for 2022. Additionally, our effective tax rate for 2022 was impacted by a gain of $9.0 million related to the change in fair value of contingent consideration issued in connection with the NORCAL acquisition, all of which was non-taxable. Our effective tax rate for 2021 was also affected by the gain on bargain purchase of $74.4 million related to the NORCAL acquisition, all of which was non-taxable. See further discussion on the contingent consideration and the gain on bargain purchase in Note 2 of the Notes to Consolidated Financial Statements. There were no other individually significant items impacting our effective tax rates for 2022 or 2021.

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FY 2021 10-K MD&A

SEC filing source: 0001875246-22-000003.

Extracted structurally from real Item 7 body heading to real Item 7A/8 boundary. Confidence: high. Filing date: 2022-02-22. Report date: 2021-12-31.

ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

The following discussion generally focuses on the change in financial condition, results of operation and cash flows for the year ended December 31, 2021 as compared to the year ended December 31, 2020 and should be read in conjunction with the Consolidated Financial Statements and Notes to those statements which accompany this report. For a full discussion of the changes in the financial condition, results of operations and cash flows for the year ended December 31, 2020 as compared to the year ended December 31, 2019, please refer to Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" section of ProAssurance's December 31, 2020 report on Form 10-K.

Throughout the discussion we use certain terms and abbreviations, which can be found in the Glossary of Terms and Acronyms at the beginning of this report. In addition, a glossary of insurance terms and phrases is available on the investor section of our website. Throughout the discussion, references to "ProAssurance," "PRA," "Company," "organization," "we," "us" and "our" refer to ProAssurance Corporation and its consolidated subsidiaries. The discussion contains certain forward-looking information that involves significant risks, assumptions and uncertainties. As discussed under the heading "Caution Regarding Forward-Looking Statements," our actual financial condition and results of operations could differ significantly from these forward-looking statements.

ProAssurance Overview

ProAssurance Corporation is a holding company for property and casualty insurance companies. Our wholly owned insurance subsidiaries provide professional liability insurance, liability insurance for medical technology and life sciences risks and workers' compensation insurance. We also provide capital to Syndicate 1729 at Lloyd's of London.

We operate in five segments which are based on our internal management reporting structure for which financial results are regularly evaluated by our CODM to determine resource allocation and assess operating performance. Descriptions of ProAssurance's five operating and reportable segments are as follows:

•Specialty P&C - This segment includes our professional liability business and medical technology liability business. Our professional liability insurance is primarily comprised of medical professional liability products offered to healthcare providers and institutions and includes the business acquired through the NORCAL transaction that closed on May 5, 2021. To a lesser extent, we also offer professional liability insurance to attorneys and their firms. Medical technology liability insurance is offered to medical technology and life sciences companies that manufacture or distribute products including entities conducting human clinical trials. We also offer custom alternative risk solutions including loss portfolio transfers, assumed reinsurance and captive cell programs for healthcare professional liability insureds. For our alternative market captive cell programs, we cede either all or a portion of the premium to certain SPCs in our Segregated Portfolio Cell Reinsurance segment.

•Workers' Compensation Insurance - This segment includes our workers' compensation insurance business which is provided primarily to employers with 1,000 or fewer employees. Our workers' compensation products include guaranteed cost policies, policyholder dividend policies, retrospectively-rated policies, deductible policies and alternative market solutions. Alternative market program premiums are 100% ceded to either SPCs in our Segregated Portfolio Cell Reinsurance segment or, to a limited extent, an unaffiliated captive insurer.

•Segregated Portfolio Cell Reinsurance - This segment includes the results (underwriting profit or loss, plus investment results, net of U.S. federal income taxes) of SPCs at Inova Re and Eastern Re, our Cayman Islands SPC operations. Each SPC is owned, fully or in part, by an individual company, agency, group or association, and the results of the SPCs are attributable to the participants of that cell. We participate to a varying degree in the results of selected SPCs and, for the SPCs in which we participate, our participation interest ranges from a low of 20% to a high of 85%. SPC results attributable to external cell participants are reflected as an SPC dividend expense (income) in our Segregated Portfolio Cell Reinsurance segment. The SPCs assume workers' compensation insurance, healthcare professional liability insurance or a combination of the two from our Workers' Compensation Insurance and Specialty P&C segments.

•Lloyd's Syndicates - This segment includes the results from our participation in Lloyd's of London Syndicate 1729 (5% for the 2021 underwriting year) and Syndicate 6131 (50% for the 2021 underwriting year). The results of this segment are normally reported on a quarter lag, except when information is available that is material to the current period. Syndicate 1729 underwrites risks over a wide range of property and casualty insurance and reinsurance lines in both the U.S. and international markets. Effective January 1, 2022, Syndicate 6131 ceased underwriting on a quota share basis with Syndicate 1729 as Syndicate 6131's business is retained within Syndicate 1729 beginning with the 2022 underwriting year. Premium from our participation in the results of Syndicate 6131 from open underwriting years prior to 2022 will continue to earn out pro rata over the entire policy period of the underlying business. Prior to January 1, 2022, Syndicate 6131 was an SPA which focused on contingency and specialty

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property business. For the 2022 underwriting year, our participation in the results of Syndicate 1729 remains unchanged at 5%.

•Corporate - This segment includes our investment operations, including the investment operations of NORCAL since the date of acquisition and excludes those reported in our Segregated Portfolio Cell Reinsurance and Lloyd's Syndicates segments. In addition, this segment includes corporate expenses, interest expense, U.S. income taxes and non-premium revenues generated outside of our insurance entities.

Additional information regarding our segments is included in Note 19 of the Notes to Consolidated Financial Statements, Part I and in the Segment Results sections that follow.

Growth Opportunities and Outlook

Over the long-term we expect our growth to come primarily through controlled expansion of our existing operations. In addition, we may identify opportunities for growth through the acquisition of other insurers, service providers or books of business. On May 5, 2021, we completed our acquisition of NORCAL Insurance Company. The addition of NORCAL broadens our geographic reach allowing us to create a truly national platform for our Healthcare Professional Liability Business. Through this greater scale, we believe we can create operating efficiencies and increase our product offerings that will allow us to deliver value to our customers, business partners and other stakeholders. See further discussion on the NORCAL acquisition in Note 2 of the Notes to Consolidated Financial Statements and under the heading "Business Combinations and Ventures" in the Liquidity and Capital Resources and Financial Condition section that follows. We continue to see new opportunities from each of our acquisitions and believe each will provide organic growth through expansion in their existing markets and relationships.

We operate in very competitive markets and face strong competition from other insurance companies for all of our insurance products. Our Specialty P&C segment includes our HCPL insurance which represents the largest product line in our consolidated gross premiums written (51% in 2021). The Specialty P&C segment also includes our Medical Technology Liability (4% in 2021) and Small Business Unit (11% in 2021) lines of business. The healthcare market in the U.S. is continuing to consolidate, which brings competitive challenges. This consolidation initially took the form of hospitals acquiring physician practices and later the growth of physician groups owned by outside investors. As these trends continue most physicians no longer practice medicine as owners of an independent practice. Large single and multi-specialty practices often operate in many states. Healthcare delivery settings are changing with the growth of retail delivery by allied healthcare professionals as well as physicians in distributed clinics, pharmacies, large consumer stores and online. These larger commercial enterprises have differing risk management needs from those in the traditional small physician practices. In response to these trends, we have enhanced our coverage offerings to fit the needs of combined hospital/physician entities, multi-state medical groups, telemedicine companies, miscellaneous facilities, allied healthcare professionals and self-insured entities even as we continue to service that portion of the market maintaining more traditional practice structures. Our Medical Technology Liability and Small Business Unit lines of business are less affected by these consolidation trends.

Our operations at Eastern, a provider of workers' compensation insurance, represents the second largest product line in our consolidated gross premiums written (25% in 2021, including alternative market premiums). The workers’ compensation market is highly competitive in our operating territories and multi-line insurers continue to leverage workers’ compensation in their product offerings, which has resulted in a reduction of new business writings. We believe our workers' compensation product offerings allow us to provide flexibility in offering solutions to our customers at a competitive price. In addition, we believe that our claims handling and risk management services are attractive to our customers and provide us with a competitive advantage even when our pricing is higher than our competitors, which has contributed to strong renewal retention.

Our Lloyd's Syndicates segment represents 4% of our consolidated gross premiums written in 2021. Effective January 1, 2022, Syndicate 6131 ceased underwriting on a quota share basis with Syndicate 1729 as Syndicate 6131's business is retained within Syndicate 1729 beginning with the 2022 underwriting year. Our participation in Syndicate 1729 for the 2014 through 2021 underwriting years has ranged from a low of 5% to a high of 62%. For the 2022 underwriting year, our participation in the results of Syndicate 1729 remains unchanged at 5%. Our participation in Syndicate 6131 ranged from a low of 50% to a high of 100% for the 2018 through 2021 underwriting years.

We believe our emphasis on the fair treatment of our insureds and other important stakeholders through our commitment to “Treated Fairly” has enhanced our market position and differentiated us from other insurers. We will continue to uphold our values of integrity, leadership, relationships and enthusiasm in all of our activities. We will honor these values in the execution of “Treated Fairly” to perform our Mission and realize our Vision. We believe that as we reach more customers with this message we will continue to improve retention and add new insureds.

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Key Performance Measures

We are committed to disciplined underwriting, pricing and loss reserving practices as well as conservative investment practices, even during difficult market conditions. We are also committed to maintaining prudent operating and financial leverage. We recognize the importance that our customers and producers place on the financial strength of our insurance subsidiaries, and we manage our business to protect our financial security.

In evaluating our performance, we consider a number of performance measures, including the following:

•The net loss ratio which is calculated as net losses and loss adjustment expenses incurred divided by net premiums earned and is a component of underwriting profitability.

•The underwriting expense ratio which is calculated as underwriting, policy acquisition and operating expenses incurred divided by net premiums earned and is a component of underwriting profitability.

•The combined ratio which is the sum of the net loss ratio and the underwriting expense ratio and measures underwriting profitability.

•The investment income ratio which is calculated as net investment income divided by net premiums earned and measures the contribution investment earnings provide to our overall profitability.

•The operating ratio which is the combined ratio, less the investment income ratio. This ratio provides the combined effect of underwriting profitability and investment income.

•The tax ratio which is calculated as total income tax expense (benefit) divided by income (loss) before income taxes and measures our effective tax rate.

•ROE which is calculated as net income (loss) divided by the average of beginning and ending shareholders’ equity. This ratio measures our overall after-tax profitability and shows how efficiently capital is being used.

•Book value per share which is calculated as total shareholders’ equity at the balance sheet date divided by the total number of common shares outstanding. This ratio measures the net worth of the Company to shareholders on a per-share basis. The declaration of dividends decreases book value per share. Growth in book value per share, adjusted for dividends declared, is an indicator of overall profitability.

In particular, we focus on our combined ratio and investment returns, both of which directly affect our ROE and growth in our book value. Currently, we target a dynamic long-term ROE of 700 basis points above the 10-year U.S. Treasury rate, which at December 31, 2021 was approximately 8.5%.

To achieve our long-term ROE target, we emphasize rate adequacy, selective underwriting, effective claims management, operational efficiency gained by leveraging our enhanced scope and scale and prudent investment management. We closely monitor premium revenues, losses and loss adjustment expenses, and underwriting and policy acquisition expenses. Our overall investment strategy is to focus on maximizing current income from our investment portfolio while maintaining appropriate credit risk, liquidity, duration, portfolio diversification and capital efficiency. While we engage in activities that generate other income, these activities, such as insurance agency services, do not constitute a significant use of our resources or a significant source of revenues or profits.

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Critical Accounting Estimates

Our Consolidated Financial Statements are prepared in conformity with GAAP. Preparation of these financial statements requires us to make estimates and assumptions that affect the amounts we report on those statements. We evaluate these estimates and assumptions on an ongoing basis based on current and historical developments, market conditions, industry trends and other information that we believe to be reasonable under the circumstances, including the potential impacts of the COVID-19 pandemic (see "Item 1A, Risk Factors" included in this report for additional information). We can make no assurance that actual results will conform to our estimates and assumptions; reported results of operations may be materially affected by changes in these estimates and assumptions.

Management considers the following accounting estimates to be critical because they involve significant judgment by management and those judgments could result in a material effect on our financial statements.

Reserve for Losses and Loss Adjustment Expenses

The largest component of our liabilities is our reserve for losses and loss adjustment expenses ("reserve for losses" or "reserve"), and the largest component of expense for our operations is incurred losses and loss adjustment expenses (also referred to as “losses and loss adjustment expenses,” “incurred losses,” “losses incurred” and “losses”). Incurred losses reported in any period reflect our estimate of losses incurred related to the premiums earned in that period as well as any changes to our previous estimate of the reserve required for prior periods.

As of December 31, 2021, our reserve is comprised almost entirely of long-tail exposures. The estimation of long-tailed losses is inherently difficult and is subject to significant judgment on the part of management. Due to the nature of our claims, our loss costs, even for claims with similar characteristics, can vary significantly depending upon many factors, including but not limited to the specific characteristics of the claim and the manner in which the claim is resolved. Long-tailed insurance is characterized by the extended period of time typically required both to assess the viability of a claim and potential damages, if any, and to reach a resolution of the claim. The claims resolution process may extend to more than five years. The combination of continually changing conditions and the extended time required for claim resolution results in a loss cost estimation process that requires actuarial skill and the application of significant judgment, and such estimates require periodic modification.

Our reserve is established by management after taking into consideration a variety of factors including premium rates, historical paid and incurred loss development trends and our evaluation of the current loss environment including frequency, severity, expected effect of inflation, general economic and social trends, and the legal and political environment. We also take into consideration the conclusions reached by our internal and consulting actuaries. We update and review the data underlying the estimation of our reserve for losses each reporting period and make adjustments to loss estimation assumptions that we believe best reflect emerging data. Both our internal and consulting actuaries perform an in-depth review of our reserve for losses on at least a semi-annual basis using the loss and exposure data of our insurance subsidiaries.

We partition our reserves by accident year, which is the year in which the claim becomes our liability. For claims-made policies, the insured event generally becomes a liability when the event is first reported to us. For occurrence policies, the insured event becomes a liability when the event takes place. For retroactive coverages, the insured event becomes a liability at inception of the underlying contract. As claims are incurred (reported) and claim payments are made, they are aggregated by accident year for analysis purposes. We also partition our reserves by reserve type: case reserves and IBNR reserves. Case reserves are established by our claims departments based upon the particular circumstances of each reported claim and represent our estimate of the future loss costs (often referred to as expected losses) that will be paid on reported claims. Case reserves are decremented as claim payments are made and are periodically adjusted upward or downward as estimates regarding the amount of future losses are revised; reported loss for an individual claim is the case reserve at any point in time plus the claim payments that have been made to date. IBNR reserves are estimated by accident year and represent our estimate in the aggregate of future development on losses that have been reported to us and our estimate of losses that have been incurred but not reported to us.

Our reserving process can be broadly grouped into three areas: the establishment of the reserve for the current accident year (the initial reserve), the re-estimation of the reserve for prior accident years (development of prior accident years) and the establishment of the initial reserve for risks assumed in business combinations, applicable only in periods in which acquisitions occur (the acquired reserve). A summary of the activity in our net reserve for losses during 2021 and 2020 is provided under the heading "Losses" in the Liquidity and Capital Resources and Financial Condition section that follows.

Current Accident Year - Initial Reserve

Considerable judgment is required in establishing our initial reserve for any current accident year period, as there is limited data available upon which to base our estimate (see further discussion that follows under the heading "Use of Judgment"). Our process for setting an initial reserve considers the unique characteristics of each product, but in general we rely heavily on the loss assumptions that were used to price business, as our pricing reflects our analysis of loss costs that we expect to incur relative to the insurance product being priced.

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Specialty P&C Segment. Loss costs within this segment are impacted by many factors including but not limited to the nature of the claim, including whether or not the claim is an individual or a mass tort claim, the personal situation of the claimant or the claimant's family, the outcome of jury trials, the legislative and judicial climate where any potential litigation may occur, general economic and social trends and, for claims involving bodily injury, the trend of healthcare costs. Within our Specialty P&C segment, for our professional liability business (88% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2021; predominately comprised of our HCPL products), we set an initial reserve based upon our evaluation of the current loss environment including frequency, severity, economic inflation, social inflation and legal trends.

The current accident year net loss ratio in the Specialty P&C segment has ranged from 87% to 106% in recent years, excluding the effect of a single large national healthcare account that generated outsized losses and distorted results for 2019 and 2020. We observed a reduction in claims frequency in 2020 that continued into 2021, some of which is due to our re-underwriting efforts while some of which we believe is associated with the COVID-19 pandemic including the disruption of the court systems. Given the consistent and prolonged nature of these favorable trends, we recognized some of these favorable frequency trends in our HCPL current accident year reserve during the third and fourth quarters of 2021. We continue to remain cautious in recognizing the full impact of these favorable trends due to the long-tailed nature of our HCPL claims as well as the uncertainty surrounding the length and severity of the pandemic. See further discussion in our Segment Results - Specialty Property & Casualty section that follows under the heading "Losses and Loss Adjustment Expenses."

The risks insured in our Medical Technology Liability business (2% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2021) are more varied, and policies are individually priced based on the risk characteristics of the policy and the account. The insured risks range from startup operations to large multinational entities, and the larger entities often have significant deductibles or self-insured retentions. Reserves are established using our most recently developed actuarial estimates of losses expected to be incurred based on factors which include results from prior analysis of similar business, industry indications, observed trends and judgment. Claims in this line of business primarily involve bodily injury to individuals and are affected by factors similar to those of our HCPL line of business. For the Medical Technology Liability business, we also establish an initial reserve using a loss ratio approach, including a provision in consideration of historical loss volatility that this line of business has exhibited.

Workers' Compensation Insurance Segment. Many factors affect the ultimate losses incurred for our workers' compensation coverages (5% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2021) including but not limited to the type and severity of the injury, the age, health and occupation of the injured worker, the estimated length of disability, medical treatment and related costs, and the jurisdiction and workers' compensation laws of the state of the injury occurrence.

We use various actuarial methodologies in developing our workers’ compensation reserve, combined with a review of the payroll exposure base. For the current accident year, given the lack of seasoned information, the different actuarial methodologies produce results with significant variability; therefore, more emphasis is placed on supplementing results from the actuarial methodologies with trends in exposure base, medical expense inflation, general inflation, severity, and claim counts, among other things, to select an ultimate loss indication.

As in our Specialty P&C segment, we observed a reduction in claims frequency in 2020. Claims frequency in 2021 continues to be below pre-pandemic levels in our Workers' Compensation Insurance segment, some of which is likely associated with the COVID-19 pandemic. While claims frequency is down, we have experienced an increase in 2021 accident year reported losses through December 31, 2021, including increased severity-related claim activity, reflecting workers returning to full employment in 2021 after the lifting of pandemic-related restrictions and the labor shortage. The increase in reported claim activity is attributable to workers being out of “work shape” as they returned to employment in 2021 as well as the lack of training, alternative work arrangements and employee fatigue due to the labor shortage.

Segregated Portfolio Cell Reinsurance Segment. The factors that affect the ultimate losses incurred for the workers' compensation and HCPL coverages assumed by the SPCs at Inova Re and Eastern Re (2% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2021) are consistent with that of our Workers’ Compensation Insurance and Specialty P&C segments, respectively.

Lloyd's Syndicates Segment. Initial reserves for Syndicate 1729 and Syndicate 6131 are primarily recorded using the loss assumptions by risk category incorporated into each Syndicate's business plan submitted to Lloyd's with consideration given to loss experience incurred to date (3% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2021). The assumptions used in each business plan are consistent with loss results reflected in Lloyd's historical data for similar risks. The loss ratios may also fluctuate due to the mix of earned premium from different open underwriting years which we participate in to varying degrees, as well as the timing of earned premium adjustments. Such adjustments may be the result of premiums for certain policies and assumed reinsurance contracts being reported subsequent to the coverage period and may be subject to adjustment based on loss experience. Premium and exposure for some of Syndicate 1729's insurance policies and reinsurance contracts are initially estimated and subsequently recorded over an extended period of time

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as reports are received under delegated underwriting authority programs. When reports are received, the premium, exposure and corresponding loss estimates are revised accordingly. Changes in loss estimates due to premium or exposure fluctuations are incurred in the accident year in which the premium is earned.

For significant property catastrophe exposures, Syndicate 1729 uses third-party catastrophe models to accumulate a listing of potentially affected policies. Each identified policy is given an estimate of loss severity based upon a combination of factors including the probable maximum loss of each policy, market share analytics, underwriting judgment, client/broker estimates and historical loss trends for similar events. These models are inherently uncertain, reliant upon key assumptions and management judgment and are not always a representation of actual events and ensuing potential loss exposure. Determination of actual losses may take an extended period of time until claims are reported and resolved, including coverage litigation.

Development of Prior Accident Years

In addition to setting the initial reserve for the current accident year, we reassess the amount of reserve required for prior accident years each period.

The foundation of our reserve re-estimation process is an actuarial analysis that is performed by both our internal and consulting actuaries. This very detailed analysis projects ultimate losses based on partitions which include line of business, geography, coverage layer and accident year. The procedure uses the most representative data for each partition, capturing its unique patterns of development and trends. We believe that the use of consulting actuaries provides an independent view of our loss data as well as a broader perspective on industry loss trends.

For the Specialty P&C, Workers' Compensation Insurance and Segregated Portfolio Cell Reinsurance segments, the analysis performed by the consulting actuaries analyzes each partition of our business in a variety of ways and uses multiple actuarial methodologies in performing these analyses, including:

•Bornhuetter-Ferguson (Paid and Reported) Method

•Paid Development Method

•Reported (Incurred) Development Method

•Average Paid Value Method

•Average Reported Value Method

A brief description of each method follows.

Bornhuetter-Ferguson Method. We use both the Paid and the Reported Bornhuetter-Ferguson Methods. The Paid Method assigns partial weight to initial expected losses for each accident year (initial expected losses being the first established case and IBNR reserves for a specific accident year) and partial weight to paid to date losses. The Reported Method assigns partial weight to the initial expected losses and partial weight to current expected losses. The weights assigned to the initial expected losses decrease as the accident year matures.

Paid Development and Reported (Incurred) Development Methods. These methods use historical, cumulative losses (paid losses for the Paid Development Method, reported losses for the Reported (Incurred) Development Method) by accident year and develop those actual losses to estimated ultimate losses based upon the assumption that each accident year will develop to estimated ultimate cost in a manner that is analogous to prior years, adjusted as deemed appropriate for the expected effects of known changes in the claim payment environment (and case reserving environment for the Reported (Incurred) Development Method); and to the extent necessary, supplemented by analyses of the development of broader industry data.

Average Paid Value and Average Reported Value Methods. In these methods, average claim cost data (paid claim cost for the Average Paid Value Method and reported claim cost for the Reported Value Method) is developed to an ultimate average cost level by report year based on historical data. Claim counts are similarly developed to an ultimate count level. The average claim cost (after rounding and adjustment, if necessary, to accommodate report year data that is not considered to be predictive) is then multiplied by the ultimate claim counts by report year to derive ultimate loss and ALAE.

Generally, methods such as the Bornhuetter-Ferguson Method are used on more recent accident years where we have less data on which to base our analysis. As time progresses and we have an increased amount of data for a given accident year, we begin to give more confidence to the development and average methods, as these methods typically rely more heavily on our own historical data. These methods emphasize different aspects of loss reserve estimation and provide a variety of perspectives for our decisions.

Certain of the methodologies utilized to estimate the ultimate losses for each partition of our reserves consider the actual amounts paid. Paid data is particularly influential when a large portion of known claims have been closed, as is the case for older accident years. In selecting a point estimate for each partition, management considers the extent to which trends are emerging consistently for all partitions and known industry trends. Thus, actual, rather than estimated severity trends are given more consideration. If actual severity trends are lower than those estimated at the time that reserves were previously

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established, the recognition of favorable development is indicated. This is particularly true for older accident years where our actuarial methodologies give more weight to actual loss costs (severity).

The various actuarial methods discussed above are applied in a consistent manner from period to period. In addition, we perform statistical reviews of claims data such as claim counts, average settlement costs and severity trends when establishing our reserves.

We utilize the selected point estimates of ultimate losses to develop estimates of ultimate losses recoverable from reinsurers, based on the terms and conditions of our reinsurance agreements. An overall estimate of the amount receivable from reinsurers is determined by combining the individual estimates. Our net reserve estimate is the gross reserve point estimate less the estimated reinsurance recovery.

For our Workers’ Compensation Insurance segment and for the workers' compensation exposures in our Segregated Portfolio Cell Reinsurance segment, we utilize the Reported (Incurred) Development Method, Paid Development Method and Bornhuetter-Ferguson Method, to develop our reserve for each accident year. The actuarial review includes the stratification of claims data (lost time claims, medical only claims) using different variations that allow us to identify trends that may not be readily identifiable if the data was evaluated only in the aggregate. Reported and paid loss development factors are key assumptions in the reserve estimation process and are based on our historical reported and paid loss development patterns. As accident years mature, the various actuarial methodologies produce more consistent loss estimates.

For our Lloyd's Syndicates segment we rely on the analysis of actual loss experience on the book of business written by Syndicate 1729 to determine loss development by accident year.

Acquired Reserve

The acquisition of NORCAL increased our gross reserves by $1.2 billion which was the fair value of NORCAL's gross loss reserve at the time of acquisition. The fair value estimate of NORCAL's gross reserve for losses and loss adjustment expenses was based on three components: an actuarial estimate of the expected future net cash flows, a reduction to those cash flows for the time value of money determined utilizing the U.S. Treasury Yield Curve and a risk margin adjustment to reflect the net present value of profit that an investor would demand in return for the assumption of the development risk associated with the reserve. The fair value of NORCAL's gross reserve, including the risk margin adjustment, exceeded the actuarial estimate of NORCAL’s undiscounted gross loss reserve by approximately $42.2 million as of May 5, 2021. This fair value adjustment was recorded to the reserve for losses and loss adjustment expenses and will be amortized over a period utilizing loss payment patterns as a reduction to prior accident year net losses and loss adjustment expenses. We also recorded other adjustments to NORCAL’s reserve as a result of purchase accounting including negative VOBA on NORCAL’s assumed unearned premium and assumed DDR reserve. See further discussion on these other purchase accounting adjustments in this section under the heading “Business Combinations” or in Note 2 of the Notes to Consolidated Financial Statements for more information.

The acquisition of Eastern on January 1, 2014 increased our loss reserve by $153.2 million which represented the fair value of Eastern's loss reserve at the time of the acquisition. The fair value of the reserve for losses and loss adjustment expenses and related reinsurance recoverables was based on an actuarial estimate of the expected future net cash flows, a reduction of those cash flows for the time value of money determined utilizing the U.S. Treasury Yield Curve, and a risk adjustment to reflect the net present value of profit that an investor would demand in return for the assumption of the associated risks. Expected net cash flows were derived from the expected loss payment patterns included in an actuarial analysis of Eastern's reserve performed as of December 31, 2013. The fair value of the reserve, including the risk margin discussed above, exceeded the undiscounted loss reserve previously established by Eastern by $9.3 million; this fair value adjustment was amortized over the average expected life of the reserve of 6 years. The fair value adjustment was fully amortized as of December 31, 2019.

Use of Judgment

The process of estimating reserves involves a high degree of judgment and is subject to a number of variables. These variables can be affected by both views of internal and external events, such as changes in views of economic inflation, legal trends and legislative changes, as well as differentiating views of individuals involved in the reserve estimation process, among others. We continually refine our estimates in a regular, ongoing process as historical loss experience develops and additional claims are reported and settled. Our objective is to consider all significant facts and circumstances known at the time.

Changes in economic conditions and steps taken by the federal government and the Federal Reserve in response to COVID-19 could lead to inflation trends that are different from those we anticipated when establishing our reserves, which could in turn lead to an increase or decrease in our loss costs and the need to strengthen or reduce reserves.

We use various actuarial methods in the process of setting reserves. Each actuarial method generally returns a different value, and for the more recent accident years the variations among the various methodologies can be significant. In order to

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project ultimate losses, we partition our reserves for analysis such as by line of business, geography, coverage layer or accident year. For each partition of our reserves, we evaluate the results of the various methods, along with the supplementary statistical data regarding such factors as closed with and without indemnity ratios, claim severity trends, the expected duration of such trends, changes in the legal and legislative environment and the current economic environment to develop a point estimate based upon management's judgment and past experience. The series of selected point estimates is then combined to produce an overall point estimate for ultimate losses.

HCPL. Over the past several years the most influential factor affecting the analysis of our HCPL reserves and the related development recognized has been an observed increase in claim severity for the broader medical professional liability industry as well as higher initial loss expectations on incurred claims. The severity trend is an explicit component of our pricing models and directly impacts the reserving process. Our estimate of this trend and our expectations about changes in this trend impact a variety of factors, from the selection of expected loss ratios to the ultimate point estimates established by management.

Because of the implicit and wide-ranging nature of severity trend assumptions on the loss reserving process, it is not practical to specifically isolate the impact of changing severity trends. However, because severity is an explicit component of our HCPL pricing process we can better isolate the impact that changing severity can have on our loss costs and loss ratios in regards to our pricing models for this business component. Our current HCPL pricing models assume severity trends in the range of 2% to 5% depending on state, territory and specialty. In some portions of our HCPL business we have observed and reflected higher severity trends in our estimates of losses and loss adjustment expenses.

Due to the long-tailed nature of our claims and the previously discussed historical volatility of loss costs, selection of a severity trend assumption is a subjective process that is inherently likely to prove inaccurate over time. Given the long tail and volatility, we are generally cautious in making changes to the severity assumptions within our pricing models. All open claims and accident years are generally impacted by a change in the severity trend, which compounds the effect of such a change.

Although the future degree and impact of the ultimate severity trend remains uncertain due to the long-tailed nature of our business, we have given consideration to observed loss costs in setting our rates. For our HCPL business, this practice had generally resulted in rate reductions as claim frequency declined and remained at historically low levels. However, from early 2017 to the current period, the average pricing on renewed business has steadily increased reflective of the rising loss cost environment, and we anticipate further renewal pricing increases due to increasing loss severity.

More recently, another factor affecting our analysis of our HCPL reserves and the related development recognized is the reduction in claims frequency in 2020, some of which is likely associated with the COVID-19 pandemic, as previously discussed. In 2020, we established a $10 million IBNR reserve related to COVID-19. Given the consistent and prolonged nature of the favorable claims frequency trend and the fact that early first notices have not materialized into claims, we recognized net favorable prior accident year reserve development of $1 million associated with our COVID-19 IBNR reserve during the third quarter of 2021. Similar to our views on our current accident year reserve, we continue to remain cautious in recognizing the full impact of these favorable frequency trends in our prior accident year reserve due to the long-tailed nature of our HCPL claims as well as the uncertainty surrounding the length and severity of the pandemic. At December 31, 2021, we maintain a $9 million IBNR reserve related to COVID-19 which represents our best estimate of future COVID-19 related losses not already captured by our claims process based on currently available information and reported incidents.

Workers' Compensation. The projection of changes in claim severity trend has not historically been an influential factor affecting our analysis of workers' compensation reserves, as claims are typically resolved more quickly than the industry norm. As previously mentioned, the determination and calculation of loss development factors, in particular, the selection of tail factors which are used to extend the projection of losses beyond historical data, requires considerable judgment.

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Loss Development by Line of Business

Professional Liability

Our professional liability line of business includes both our HCPL and Small Business Unit lines, with our HCPL line representing the largest component of our reserve. Our HCPL line of business also includes the business acquired through the NORCAL transaction that closed on May 5, 2021. In support of our concern that the decline in frequency will result in a higher severity trend for our HCPL claims, we saw our closed-with-indemnity-payment ratio (i.e., the number of claims closed with an indemnity or loss payment as compared to the total number of closed claims) for our claims increase from 15% in 2012 to 18% in 2021 (ratios exclude NORCAL claims).

The following table presents additional information about the loss development for our professional liability line of business, excluding loss development for HCPL coverages assumed by the SPCs at Inova Re and Eastern Re. Furthermore, loss development for our professional liability line of business for the year ended December 31, 2021 includes the business acquired through the NORCAL transaction since the date of acquisition, excluding the amortization of the purchase accounting fair value adjustment:

($ in thousands)202120202019
Accident YearsEstimated Ultimate Losses, Net of Reinsurance, December 31, 2021Reserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims Closed
2021$397,814N/A25.9%N/AN/AN/AN/A
2020$480,001$(4,947)54.1%N/A22.0%N/AN/A
2019$493,573$(20,426)73.7%$1,36148.7%N/A25.3%
2018$527,420$9,41881.0%$1,21865.1%$69,51846.9%
2017$433,764$(2,342)88.4%$(2,741)77.9%$35,59167.8%
2016$400,534$(2,739)89.5%$(1,760)88.8%$1,84882.1%
2015$369,185$6,01197.1%$(4,489)93.7%$(27,495)89.6%
2014$325,486$(1,017)98.5%$(8,930)96.6%$(17,412)93.9%
2013$358,696$(260)98.9%$(133)98.0%$(12,799)96.9%
2012$374,938$(2,999)99.5%$(1,835)99.2%$(9,173)98.7%
Prior to 2012$8,282,412$2,389$(1,578)$(21,572)

Development recognized during 2021 principally related to accident years 2015 through 2020. In addition, we recognized favorable prior year reserve development of $1 million in 2021 related to the 2020 accident year associated with our COVID-19 IBNR reserve, as previously discussed, due to the fact that early first notices have not materialized into claims. We continue to remain cautious in our evaluation of our prior accident year reserve due to the long-tailed nature of our HCPL claims as well as the uncertainty surrounding the length and severity of the pandemic. Not included in the table above, is $7.9 million of amortization of the purchase accounting fair value adjustment on NORCAL's assumed net reserve and amortization of the negative VOBA associated with NORCAL's DDR reserve which is recorded as a reduction to prior accident year net losses and loss adjustment expenses in 2021. We have not recognized any development related to NORCAL's prior accident year reserves since the date of acquisition. See Note 2 of the Notes to Consolidated Financial Statements for additional information on the NORCAL acquisition and the related purchase accounting adjustments. Development recognized during 2020 principally related to accident years 2014 through 2017. Not included in the above table, as previously discussed, is $2.5 million and $4.4 million of favorable development recognized during 2021 and 2020, respectively, in our Segregated Portfolio Cell Reinsurance segment related to the HCPL coverages assumed by the SPCs at Inova Re and Eastern Re. During 2019 the loss experience in our Specialty line of business deteriorated further, particularly in regard to the reserves we established for a large national healthcare account. This deterioration is the primary driver of the unfavorable development we recognized in 2019 for accident years 2016 through 2018.

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This can also be seen in looking at both the absolute amount of reserve development recognized for the less developed accident years as well as the size of such development when compared to established ultimates for those same accident years at the end of the preceding calendar year. The following table provides this information for years ended December 31, 2021, 2020 and 2019 with respect to the three then most recent prior accident years:

($ in millions)202120202019
Prior accident years2018-20202017-20192016-2018
Net favorable (unfavorable) development recognized for the specified years$16.0$0.2$(107.0)
Development as a % of established ultimates, prior calendar year end1.1%%(8.5%)

Medical Technology Liability

Our Medical Technology Liability line of business has not experienced the change in claims frequency previously described for HCPL. However, the nature of the risks insured and volatility of the loss experience in this line of business has produced more variable loss development, as presented in the following table:

($ in thousands)202120202019
Accident YearsEstimated Ultimate Losses, Net of Reinsurance, December 31, 2021Reserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims Closed
2021$16,929N/A32.0%N/AN/AN/AN/A
2020$14,489$(248)59.2%N/A41.0%N/AN/A
2019$13,584$72247.5%$(1,047)41.8%N/A13.4%
2018$8,807$(3,091)85.1%$(352)75.2%$(1,856)68.2%
2017$6,017$(2,192)94.1%$(3,854)90.1%$(2,166)85.6%
2016$8,611$(2,126)97.3%$(486)96.7%$(1,249)65.9%
2015$7,983$(638)97.0%$(663)96.3%$(1,548)85.8%
2014$9,374$(317)99.6%$(458)98.9%$(1,823)94.3%
2013$4,600$(128)100.0%$(294)100.0%$(291)98.7%
2012$8,423$(12)99.2%$(69)99.2%$(1,362)99.2%
Prior to 2012$585,081$(94)$(1,370)$(2,470)

Approximately $7.6 million of the $8.1 million total net favorable development recognized in 2021 related to the 2015 through 2020 accident years. The development for the 2015 through 2020 accident years represents an 11.3% reduction to the ultimates established for those reserves at December 31, 2020. Approximately $5.3 million of the $8.6 million total net favorable development recognized in 2020 related to the 2017 through 2019 accident years. The development for the 2017 through 2019 accident years represents a 13.7% reduction to the ultimates established for those reserves at December 31, 2019. Approximately $6.8 million of the $12.8 million total net favorable development recognized in 2019 related to the 2014 through 2017 accident years. The development for the 2014 through 2017 accident years represents a 13.7% reduction to the ultimates established for those reserves at December 31, 2018.

In 2021, 2020 and 2019 the development was largely attributable to favorable results from claims closed during the year. As time has elapsed we have recognized that actual loss experience has on average been better than estimated. We have been cautious in recognizing the improvement, but as claims have matured and claims are closed or have become more certain for the remaining open claims, we have revised reserve estimates. We believe the need for a cautious approach is required as outcomes are uncertain and results can be significantly affected by outcomes for a small number of cases.

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Workers' Compensation

Claims in our workers’ compensation line of business have historically closed at a faster rate than in our HCPL or Medical Technology Liability lines of business. This faster disposition rate, along with a lower net retention after the application of reinsurance, has resulted in less volatility in loss estimates on a net basis. However, a change in the number of individually-severe claims can create volatility in a given accident year. The following table presents additional information about the loss development for our workers' compensation line of business:

($ in thousands)202120202019
Accident YearsEstimated Ultimate Losses, Net of Reinsurance, December 31, 2021Reserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims ClosedReserve Development (favorable) unfavorable% of Known Claims Closed
2021$145,232N/A45.4%N/AN/AN/AN/A
2020$141,076$(1,493)85.1%N/A41.6%N/AN/A
2019$154,166$(4,030)92.1%$(6,160)81.6%N/A43.0%
2018$159,563$(1,503)95.2%$58491.7%$(2,561)81.8%
2017$129,533$(2,375)97.3%$(3,372)96.0%$(4,349)91.4%
2016$110,633$(1,230)97.8%$(3,048)97.1%$(8,923)95.2%
2015$117,792$(1,538)98.4%$(3,919)98.0%$(2,128)96.9%
2014$117,939$(873)99.3%$(2,136)98.9%$(363)98.9%
2013$114,460$(646)99.5%$(592)99.5%$2,40599.4%
2012$94,295$(383)99.7%$(126)99.7%$(72)99.7%
Prior to 2012$563,334$(649)$(403)$(399)

In 2021, we recognized $7.6 million of net favorable development in our Segregated Portfolio Cell Reinsurance segment related to workers' compensation business and $7.1 million of net favorable development in our Workers' Compensation Insurance segment. In 2020, we recognized $12.1 million of net favorable development in our Segregated Portfolio Cell Reinsurance segment related to workers' compensation business and $7.0 million of net favorable development in our Workers' Compensation Insurance segment. In 2019, we recognized $10.1 million of net favorable development in our Segregated Portfolio Cell Reinsurance segment, all related to workers' compensation business, and $7.8 million of net favorable development in our Workers' Compensation Insurance segment. Not included in the table above, net favorable development in our Workers' Compensation Insurance segment in 2019 included $1.6 million related to the amortization of the purchase accounting fair value adjustment. As previously discussed, this fair value adjustment has been fully amortized as of December 31, 2019.

Variability of Loss Reserves

As previously noted, the number of data points and variables considered and the subjective process followed in establishing our loss reserve makes it impractical to isolate individual variables and demonstrate their impact on our estimate of loss reserves. However, to provide a better understanding of the potential variability in our reserves, we have modeled implied reserve ranges around our single point net reserve estimates for our various lines of business assuming different confidence levels. The ranges have been developed by aggregating the expected volatility of losses across partitions of our business to obtain a consolidated distribution of potential reserve outcomes. The aggregation of this data takes into consideration correlations among our geographic and specialty mix of business. The result of the correlation approach to aggregation is that the ranges are narrower than the sum of the ranges determined for each partition.

We have used this modeled statistical distribution to calculate an 80% and 60% confidence interval for the potential outcome of our consolidated net reserve for losses. The high and low end points of the distributions are as follows:

Low End PointCarried Net ReserveHigh End Point
80% Confidence Level$2.327 billion$3.128 billion$4.051 billion
60% Confidence Level$2.540 billion$3.128 billion$3.651 billion

Any change in our estimate of net ultimate losses for prior years is reflected in net income (loss) in the period in which such changes are made.

Due to the size of our consolidated reserve for losses and the large number of claims outstanding at any point in time, even a small percentage adjustment to our total reserve estimate could have a material effect on our results of operations for the period in which the adjustment is made, as was the case in 2021, 2020 and 2019.

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Reinsurance

We use insurance and reinsurance (collectively, “reinsurance”) to provide capacity to write larger limits of liability, to provide reimbursement for losses incurred under the higher limit coverages we offer, to provide protection against losses in excess of policy limits and, in the case of risk sharing arrangements, to align our objectives with those of our strategic business partners and to provide custom insurance solutions for large customer groups. The purchase of reinsurance does not relieve us from the ultimate risk on our policies; however, it does provide reimbursement for certain losses we pay.

We make a determination of the amount of insurance risk we choose to retain based upon numerous factors, including our risk tolerance and the capital we have to support it, the price and availability of reinsurance, the volume of business, our level of experience with a particular set of exposures and our analysis of the potential underwriting results. We purchase excess of loss reinsurance to limit the amount of risk we retain and we do so from a number of companies to mitigate concentrations of credit risk. As of December 31, 2021, there is no reinsurer, on an individual basis, for which our recoverables for both paid and unpaid claims (net of amounts due to the reinsurer) and our prepaid balances are more than $52 million, in aggregate. We utilize reinsurance brokers to assist us in the placement of these reinsurance programs and in the analysis of the credit quality of our reinsurers. The determination of which reinsurers we choose to do business with is based upon an evaluation of their then current financial strength, rating, stability and claims payment practices.

We evaluate each of our ceded reinsurance contracts at inception to confirm that there is sufficient risk transfer to allow the contract to be accounted for as reinsurance under current accounting guidance. At December 31, 2021, all ceded contracts were accounted for as risk transferring contracts.

Our receivable from reinsurers on unpaid losses and loss adjustment expenses represents our estimate of the amount of our reserve for losses that will be recoverable under our reinsurance programs. We base our estimate of funds recoverable upon our expectation of ultimate losses and the portion of those losses that we estimate to be allocable to reinsurers based upon the terms and conditions of our reinsurance agreements. Our assessment of the collectability of the recorded amounts receivable from reinsurers considers the payment history of the reinsurer, publicly available financial and rating agency data, our interpretation of the underlying contracts and policies and responses by reinsurers.

Given the uncertainty inherent in our estimates of losses and related amounts recoverable from reinsurers, these estimates may vary significantly from the ultimate outcome.

Under the terms of certain of our reinsurance agreements, the amount of premium that we cede to our reinsurers is based in part on the losses we recover under the agreements. Therefore, we make an estimate of premiums ceded under these reinsurance agreements subject to certain minimums and maximums. Any adjustments to our estimates of losses recoverable under our reinsurance agreements or the premiums owed under our agreements are reflected in current operations. Due to the size of our reinsurance balances, an adjustment to these estimates could have a material effect on our results of operations for the period in which the adjustment is made.

Our reinsurance receivables are exposed to credit losses but to date have not experienced any significant amount of credit losses. To partially mitigate our exposure to credit losses, reinsurance receivables totaling approximately $97.9 million were collateralized by letters of credit or funds withheld as of December 31, 2021. We measure expected credit losses on our reinsurance receivables on a collective basis when similar risk characteristics exist or on an individual basis if we determine a receivable does not share similar risk characteristics. We measure expected credit losses associated with our reinsurance receivables (related to both paid and unpaid losses) at the consolidated level as our reinsurance receivables share similar risk characteristics including type of financial asset, type of industry and similar historical and expected credit loss patterns. We measure expected credit losses over the average contractual term of our reinsurance receivables utilizing a loss rate method. Historical internal credit loss experience is the basis for our assessment of expected credit losses; however, we may also consider historical credit loss information from external sources. We also consider reasonable and supportable forecasts of future economic conditions in our estimate of expected credit losses. Expected credit losses associated with our reinsurance receivables (related to both paid and unpaid losses) were nominal in amount as of December 31, 2021 and 2020. No reinsurance balances were written off for credit reasons during the years ended December 31, 2021 or 2020. Should our expected credit loss analysis or other facts or circumstances lead us to believe that any reinsurer may not meet its obligations to us, adjustments to the allowance for expected credit losses or to reinsurance receivables would be reflected in current operations. Such an adjustment has the potential to be material to the results of operations in the period in which it is recorded; however, we would not expect such an adjustment to have a material effect on our capital position or our liquidity. For further information on our allowance for expected credit losses related to our receivables from reinsurers see Note 1 of the Notes to Consolidated Financial Statements.

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Investment Valuations

We record the majority of our investments at fair value as shown in the table below. At December 31, 2021, the distribution of our investments based on GAAP fair value hierarchies (levels) was as follows:

Distribution by GAAP Fair Value Hierarchy
Level 1Level 2Level 3Not CategorizedTotal Investments
Investments recorded at:
Fair value8%82%1%6%97%
Other valuations3%
Total Investments100%

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. All of our fixed maturity and equity investments are carried at fair value. The fair value of our short-term securities approximates the cost of the securities due to their short-term nature.

Because of the number of securities we own and the complexity of developing accurate fair values, we utilize multiple independent pricing services to assist us in establishing the fair value of individual securities. The pricing services provide fair values based on exchange-traded prices, if available. If an exchange-traded price is not available, the pricing services, if possible, provide a fair value that is based on multiple broker/dealer quotes or that has been developed using pricing models. Pricing models vary by asset class and utilize currently available market data for securities comparable to ours to estimate a fair value for our securities. The pricing services scrutinize market data for consistency with other relevant market information before including the data in the pricing models. The pricing services disclose the types of pricing models used and the inputs used for each asset class. Determining fair values using these pricing models requires the use of judgment to identify appropriate comparable securities and to choose a valuation methodology that is appropriate for the asset class and available data.

The pricing services provide a single value per instrument quoted. We review the values provided for reasonableness each quarter by comparing market yields generated by the supplied value versus market yields observed in the marketplace. We also compare yields indicated by the provided values to appropriate benchmark yields and review for values that are unchanged or that reflect an unanticipated variation as compared to prior period values. We utilize a primary pricing service for each security type and compare provided information for consistency with alternate pricing services, known market data and information from our own trades, considering both values and valuation trends. We also review weekly trades versus the prices supplied by the services. If a supplied value appears unreasonable, we discuss the valuation in question with the pricing service and make adjustments if deemed necessary. Historically our review has not resulted in any material changes to the values supplied by the pricing services. The pricing services do not provide a fair value unless an exchange-traded price or multiple observable inputs are available. As a result, the pricing services may provide a fair value for a security in some periods but not others, depending upon the level of recent market activity for the security or comparable securities.

Level 1 Investments

Fair values for a majority of our equity securities and portions of our short-term and convertible securities are determined using exchange-traded prices. There is little judgment involved when fair value is determined using an exchange-traded price. In accordance with GAAP, we classify securities valued using an exchange-traded price as Level 1 securities.

Level 2 Investments

Most fixed income securities do not trade daily; thus, exchange-traded prices are generally not available for these securities. However, market information (often referred to as observable inputs or market data, including but not limited to, last reported trade, non-binding broker quotes, bids, benchmark yield curves, issuer spreads, two-sided markets, benchmark securities, offers and recent data regarding assumed prepayment speeds, cash flow and loan performance data) is available for most of our fixed income securities. We determine fair value for a large portion of our fixed income securities using available market information. In accordance with GAAP, we classify securities valued based on multiple market observable inputs as Level 2 securities.

Level 3 Investments

When a pricing service does not provide a value for one of our fixed maturity securities, management estimates fair value using either a single non-binding broker quote or pricing models that utilize market based assumptions which have limited observable inputs. The process involves significant judgment in selecting the appropriate data and modeling techniques to use in the valuation process. In accordance with GAAP, we classify securities valued using limited observable inputs as Level 3 securities.

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Fair Values Not Categorized

We hold interests in certain investment funds, primarily LPs/LLCs, which measure fund assets at fair value on a recurring basis and provide us with a NAV for our interest. As a practical expedient, we consider the NAV provided to approximate the fair value of the interest. In accordance with GAAP, we do not categorize these investments within the fair value hierarchy.

Nonrecurring Fair Value Measurements

We measure the fair value of certain assets on a nonrecurring basis when events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. These assets include investments carried principally at cost, investments in tax credit partnerships, fixed assets, goodwill and other intangible assets. These assets would also include any equity method investments that do not provide a NAV. During the third quarter of 2020, we recognized a nonrecurring fair value measurement related to the goodwill in our Specialty P&C reporting unit with a carrying value of $161.1 million prior to the fair value measurement. This nonrecurring fair value measurement resulted in the goodwill being written down to its implied fair value of zero resulting in an impairment of the goodwill of $161.1 million (see following discussion under the heading "Goodwill / Intangibles" and Note 8 of the Notes to Consolidated Financial Statements). The inputs used in the fair value measurement were non-observable and, as such, were categorized as a Level 3 valuation. We did not have any other assets or liabilities that were measured at fair value on a nonrecurring basis at December 31, 2021 or December 31, 2020.

Investments - Other Valuation Methodologies

Certain of our investments, in accordance with GAAP for the type of investment, are measured using methodologies other than fair value. At December 31, 2021, these investments represented approximately 3% of total investments, and are detailed in the following table. Additional information about these investments is provided in Note 3 and Note 4 of the Notes to Consolidated Financial Statements.

(In millions)Carrying ValueGAAP Measurement Method
Other investments:
Other, principally FHLB capital stock$3.2Principally Cost
Investment in unconsolidated subsidiaries:
Investments in tax credit partnerships12.4Equity
Equity method investments, primarily LPs/LLCs52.3Equity
64.7
BOLI81.8Cash surrender value
Total investments - Other valuation methodologies$149.7

Impairments

We evaluate our available-for-sale investment securities, which at December 31, 2021 and December 31, 2020 consisted entirely of fixed maturity securities, on at least a quarterly basis for the purpose of determining whether declines in fair value below recorded cost basis represent an impairment loss. We consider a credit-related impairment loss to have occurred:

•if there is intent to sell the security;

•if it is more likely than not that the security will be required to be sold before full recovery of its amortized cost basis; or

•if the entire amortized basis of the security is not expected to be recovered.

The assessment of whether the amortized cost basis of a security is expected to be recovered requires management to make assumptions regarding various matters affecting future cash flows. The choice of assumptions is subjective and requires the use of judgment. Actual credit losses experienced in future periods may differ from management’s estimates of those credit losses. Methodologies used to estimate the present value of expected cash flows are:

The estimate of expected cash flows is determined by projecting a recovery value and a recovery time frame and assessing whether further principal and interest will be received. We consider various factors in projecting recovery values and recovery time frames, including the following:

•third-party research and credit rating reports;

•the current credit standing of the issuer, including credit rating downgrades, whether before or after the balance sheet date;

•the extent to which the decline in fair value is attributable to credit risk specifically associated with the security or its issuer;

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•internal assessments and the assessments of external portfolio managers regarding specific circumstances surrounding an investment, which indicate the investment is more or less likely to recover its amortized cost than other investments with a similar structure;

•for asset-backed securities, the origination date of the underlying loans, the remaining average life, the probability that credit performance of the underlying loans will deteriorate in the future and our assessment of the quality of the collateral underlying the loan;

•failure of the issuer of the security to make scheduled interest or principal payments;

•any changes to the rating of the security by a rating agency;

•recoveries or additional declines in fair value subsequent to the balance sheet date;

•adverse legal or regulatory events;

•significant deterioration in the market environment that may affect the value of collateral (e.g., decline in real estate prices);

•significant deterioration in economic conditions; and

•disruption in the business model resulting from changes in technology or new entrants to the industry.

If deemed appropriate and necessary, a discounted cash flow analysis is performed to confirm whether a credit loss exists and, if so, the amount of the credit loss. We use the single best estimate approach for available-for-sale debt securities and consider all reasonably available data points, including industry analyses, credit ratings, expected defaults and the remaining payment terms of the debt security. For fixed rate available-for-sale debt securities, cash flows are discounted at the security's effective interest rate implicit in the security at the date of acquisition. If the available-for-sale debt security’s contractual interest rate varies based on subsequent changes in an independent factor, such as an index or rate, for example, the prime rate, the LIBOR, or the U.S. Treasury bill weekly average, that security’s effective interest rate is calculated based on the factor as it changes over the life of the security. If we intend to sell a debt security or believe we will more likely than not be required to sell a debt security before the amortized cost basis is recovered, any existing allowance will be written off against the security's amortized cost basis, with any remaining difference between the debt security's amortized cost basis and fair value recognized as an impairment loss in earnings.

Exclusive of securities where there is an intent to sell or where it is not more likely than not that the security will be required to be sold before recovery of its amortized cost basis, impairment for debt securities is separated into a credit component and a non-credit component. The credit component of an impairment is the difference between the security’s amortized cost basis and the present value of its expected future cash flows, while the non-credit component is the remaining difference between the security’s fair value and the present value of expected future cash flows. An allowance for expected credit losses will be recorded for the expected credit losses through income and the non-credit component is recognized in OCI. The amount of impairment recognized is limited to the excess of the amortized cost over the fair value of the available-for-sale debt security.

Pension

As a result of our NORCAL acquisition, we sponsor a frozen qualified defined benefit pension plan which covers substantially all NORCAL employees (except those that were previous employees of Medicus Insurance Company and FD Insurance Company, employees of PPM RRG as well as new hires after December 31, 2013). Accounting for pension benefits requires the use of assumptions for the valuation of the PBO and the expected performance of the plan assets.

We use December 31 as the measurement date for calculating our obligation related to this defined benefit pension plan and for estimating net periodic benefit cost (credit) for the subsequent year. The PBO for pension benefits represents the present value of all future benefits earned as of the measurement date for vested and non-vested employees. At each measurement date, we review the various assumptions impacting the amounts recorded for the pension plan including the discount rates, which impacts the recorded value of the PBO and interest costs, and the expected return on plan assets.

To estimate the discount rate at the measurement date, we use a bond yield curve model, developed based on pricing and yield information for high quality corporate bonds. The assumption for the expected return on plan assets is based on the anticipated returns that will be earned by the portfolio over the long-term. The expected return on plan assets is influenced, but not determined, by historical portfolio performance. We assumed a 3.75% expected return on plan assets on our pension plan assets for the year ended December 31, 2021. For 2022, we increased our expected return on plan assets assumption to 4.0% based on our long-term outlook for the capital markets.

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The following table summarizes the estimated changes in our projected benefit obligation and net periodic benefit cost (income) for a hypothetical change in our discount rate and expected return on plan assets:

Shift in Basis Points
December 31, 2021
($ in millions)(100)Current100
Change in Discount Rate:
Benefit Obligation$124.1$106.9$93.1
Net periodic benefit cost (income)$(0.5)$(0.5)$(0.5)
Change in Expected Return on Plan Assets:
Net periodic benefit cost (income)$0.2$(0.5)$(1.2)

Accounting standards provide for the delayed recognition of differences between actual results and expected or estimated results. This delayed recognition of the differences is amortized into earnings over time. The differences between actual results and expected or estimated results are recognized in full in AOCI. Amounts recognized in AOCI are reclassified to earnings in a systematic manner over the average future service period of participants. During 2022, we expect to recognize net pension income of approximately $1.1 million and we do not expect that contributions to the pension plan will be required during 2022 nor do we anticipate making any discretionary contributions.

Deferred Policy Acquisition Costs

Policy acquisition costs (primarily commissions, premium taxes and underwriting salaries) which are directly related to the successful acquisition of new and renewal premiums are capitalized as DPAC and charged to expense, net of ceding commissions earned, as the related premium revenue is recognized. We evaluate the recoverability of our DPAC typically at the segment level each reporting period or in a manner that is consistent with the way we manage our business. Any amounts estimated to be unrecoverable are charged to expense in the current period.

As part of our evaluation of the recoverability of DPAC, we also evaluate our unearned premiums for premium deficiencies. A premium deficiency is recognized if the sum of anticipated losses and loss adjustment expenses, unamortized DPAC and maintenance costs, net of anticipated investment income, exceeds the related unearned premium. If a premium deficiency is identified, the associated DPAC is written off, and a PDR is recorded for the excess deficiency as a component of net losses and loss adjustment expenses in our Consolidated Statements of Income and Comprehensive Income and as a component of the reserve for losses and loss adjustment expenses on our Consolidated Balance Sheets. For the years ended December 31, 2021 and 2020, we did not determine any DPAC to be unrecoverable. For the year ended December 31, 2019, a nominal amount of DPAC was charged to expense as it was determined to be unrecoverable and a $9.2 million PDR was established in our Specialty P&C segment related to a large national healthcare account. The $9.2 million PDR was fully amortized during 2020.

Deferred Taxes

Deferred federal income taxes arise from the recognition of temporary differences between the basis of assets and liabilities determined for financial reporting purposes and the basis determined for income tax purposes. Our temporary differences principally relate to our loss reserves, unearned and advanced premiums, DPAC, NOL and tax credit carryforwards, compensation related items, unrealized investment gains (losses) and basis differences on fixed assets, intangible assets and operating leases. Deferred tax assets and liabilities are measured using the enacted tax rates expected to be in effect when such benefits are realized. We review our deferred tax assets quarterly for impairment. If we determine that it is more likely than not that some or all of a deferred tax asset will not be realized, a valuation allowance is recorded to reduce the carrying value of the asset. In assessing the need for a valuation allowance, management is required to make certain judgments and assumptions about our future operations based on historical experience and information as of the measurement period regarding reversal of existing temporary differences, carryback capacity, future taxable income of the appropriate character (including its capital and operating characteristics) and tax planning strategies.

A valuation allowance was established in a prior year against the deferred tax asset related to the NOL carryforwards for the U.K. operations and in 2020 against a portion of the deferred tax asset related to the U.S. state NOL carryforwards. In addition, a valuation allowance was established in 2021 against the net deferred tax asset of ProAssurance American Mutual, a Risk Retention Group. As a taxpayer separate from the consolidated group, this entity has experienced cumulative losses in recent years. Management concluded that it was more likely than not that these deferred tax assets will not be realized. We also established a valuation allowance in a prior year against the deferred tax assets of certain SPCs at our wholly owned Cayman Islands reinsurance subsidiary, Inova Re. Due to the cumulative losses incurred in recent years by these SPCs, management

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concluded that a valuation allowance was required. We evaluated the realizability of the deferred tax assets acquired from NORCAL during our accounting for the acquisition and management concluded that it was more likely than not that the acquired deferred tax assets would be realized. As of December 31, 2021, management concluded that the previously recorded valuation allowances were still required against the deferred tax assets related to the NOL carryforwards for the U.K. operations, against the deferred tax assets related to the U.S. state NOL carryforwards and against the deferred tax assets of certain SPCs at Inova Re. Management’s assessment of the need for these valuation allowances at December 31, 2021 included an analysis of the available sources of income, including projections of income for the consolidated group following the NORCAL acquisition. See further discussion on ProAssurance’s deferred tax assets in Note 7 of the Notes to Consolidated Financial Statements.

U.S. Tax Legislation

Coronavirus Aid, Relief and Economic Security Act

In response to COVID-19, the CARES Act was signed into law on March 27, 2020 and contains several provisions for corporations and eased certain deduction limitations originally imposed by the TCJA. See further discussion in Note 7 of the Notes to Consolidated Financial Statements. Temporary changes regarding NOL carryback provisions included in the CARES Act had a favorable impact on our liquidity, as we were able to carryback our 2019 and 2020 net operating losses to claim refunds (see discussion that follows in the Liquidity and Capital Resources and Financial Condition section under the heading "Taxes"). See further discussion in Note 7 of the Notes to Consolidated Financial Statements.

American Rescue Plan Act of 2021

In response to economic concerns associated with COVID-19, the American Rescue Plan Act of 2021 was signed into law on March 11, 2021 and includes an expansion of the number of employees covered by the limitation on the deductibility of compensation in excess of $1 million. This provision is effective for tax years beginning after December 31, 2026. We have evaluated this provision as well as the other provisions of the American Rescue Plan Act of 2021 and concluded that they will not have a material impact on our financial position or results of operations as of December 31, 2021. See further discussion in Note 7 of the Notes to Consolidated Financial Statements.

Unrecognized Tax Benefits

We evaluate tax positions taken on tax returns and recognize positions in our financial statements when it is more likely than not that we will sustain the position upon resolution with a taxing authority. If recognized, the benefit is measured as the largest amount of benefit that has a greater than 50% probability of being realized. We review uncertain tax positions each quarter, considering changes in facts and circumstances, such as changes in tax law, interactions with taxing authorities and developments in case law, and make adjustments as we consider necessary. Adjustments to our unrecognized tax benefits may affect our income tax expense, and settlement of uncertain tax positions may require the use of cash. Other than differences related to timing, no significant adjustments were considered necessary during 2021 or 2020. At December 31, 2021, our liability for unrecognized tax benefits approximated $3.0 million.

Goodwill / Intangibles

Goodwill and intangible assets are tested for impairment annually or more frequently if circumstances indicate an impairment may have occurred. The date of our annual impairment testing is October 1. Impairment of goodwill is tested at the reporting unit level, which is consistent with our reportable segments identified in Note 19 of the Notes to Consolidated Financial Statements.

Interim Impairment Assessments

During the third quarter of 2020, we performed interim impairment assessments of the goodwill and definite and indefinite lived intangible assets in our Specialty P&C, Workers' Compensation Insurance and Segregated Portfolio Cell Reinsurance reporting units due to the significant market volatility impacting our actual and projected results along with a decline in our stock price. The goodwill analysis indicated an impairment of the goodwill associated with our Specialty P&C reporting unit and accordingly we recorded a $161.1 million charge to goodwill (see further discussion in Note 8 of the Notes to Consolidated Financial Statements). The analysis of our definite and indefinite lived intangible assets indicated no impairment at September 30, 2020.

Annual Impairment Assessment

When testing goodwill for impairment on our annual test date, we have the option to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more likely than not that the estimated fair value of a reporting unit is less than its carrying amount. If we elect to perform a qualitative assessment and

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determine that an impairment is more likely than not, we are then required to perform a quantitative impairment test; otherwise, no further analysis is required. We also may elect not to perform the qualitative assessment and, instead, proceed directly to the quantitative impairment test.

Performance of the qualitative goodwill impairment assessment requires judgment in identifying and considering the significance of relevant key factors, events, and circumstances that affect the fair values of our reporting units. This requires consideration and assessment of external factors such as macroeconomic, industry, and market conditions, as well as entity-specific factors, such as our actual and planned financial performance. We also give consideration to the difference between each reporting unit's fair value and carrying value as of the most recent date that a fair value measurement was performed. If the results of the qualitative assessment conclude that it is not more likely than not that the fair value of a reporting unit exceeds its carrying value, additional quantitative impairment testing is performed.

The quantitative goodwill impairment test involves comparing the fair value of a reporting unit with its carrying value including goodwill. If the fair value of a reporting unit exceeds its carrying value, the reporting unit's goodwill is considered not to be impaired. However, if the carrying value of a reporting unit exceeds its fair value, an impairment loss is recorded in an amount equal to that excess. Any impairment charge recognized is limited to the amount of the respective reporting unit's allocated goodwill.

Determining the fair value of a reporting unit under the quantitative goodwill impairment test requires judgment and often involves the use of significant estimates and assumptions, including an assessment of external factors such as macroeconomic, industry, and market conditions, as well as entity-specific factors, such as actual and planned financial performance. These estimates and assumptions could have a significant impact on whether or not an impairment charge is recognized and the magnitude of any such charge. To assist management in the process of determining any potential goodwill impairment, we may review and consider appraisals from accredited independent valuation firms. Estimates of fair value are primarily determined using discounted cash flows and market comparisons. These approaches involve significant estimates and assumptions, including projected future cash flows (including timing), discount rates reflecting the risks inherent in those future cash flows, perpetual growth rates, and selection of appropriate market comparable metrics and transactions.

During 2021, we experienced an increase in accident year reported losses, including increased severity-related claim activity in our Workers' Compensation Insurance segment. We primarily attribute this increase in reported losses and severity-related claim activity to workers being out of “work shape” as they returned to employment in 2021, as well as the lack of training, alternative work arrangements and employee fatigue due to the labor shortage. As a result, we increased our 2021 current accident year loss ratio in our Workers' Compensation Insurance reporting unit during the third quarter of 2021. Due to the increase in the current accident year loss ratio, management decided to bypass the optional qualitative impairment test and proceed directly to the quantitative impairment test for both the Workers’ Compensation Insurance and Segregated Portfolio Cell Reinsurance reporting units for the most recent goodwill impairment test performed on October 1, 2021. In applying the quantitative approach, management estimated the fair value of the Workers' Compensation Insurance and Segregated Portfolio Cell Reinsurance reporting units using both an income approach and market approach using the aforementioned valuation methodologies and process for developing assumptions. To corroborate the reporting units’ valuation, we performed a reconciliation of the estimate of the aggregate fair value of the reporting units to ProAssurance's market capitalization, including consideration of a control premium. As a result of the quantitative assessments, management concluded that the fair value of each of the Workers Compensation Insurance and Segregated Portfolio Cell Reinsurance reporting units exceeded the carrying value as of the testing date; therefore, goodwill was not impaired and no further goodwill impairment testing was required. No goodwill impairment was recorded during the year ended December 31, 2021. See Note 8 of the Notes to Consolidated Financial Statements for additional information about our goodwill. The analysis of our definite and indefinite lived intangible assets indicated no impairment at December 31, 2021.

Acquired Intangibles

The acquisition of NORCAL added $14 million to identifiable intangible assets as of the acquisition date. Intangible assets acquired in the NORCAL acquisition included the following:

(In thousands)Estimated Fair Value on Acquisition DateEstimated Useful Life
Trade name$1,0003
Licenses13,000Indefinite
Total$14,000

See further information on the intangible assets acquired in the NORCAL acquisition in Note 2 of the Notes to Consolidated Financial Statements and additional information regarding our goodwill and intangible assets is included in Note 1 and Note 8 of the Notes to Consolidated Financial Statements.

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Business Combinations

We accounted for our acquisition of NORCAL in accordance with GAAP relating to business combinations which required us to make certain estimates and assumptions including determining the fair value of the non-cash components of the acquisition consideration and the acquisition date fair values of the acquired tangible and identifiable intangible assets and assumed liabilities of NORCAL. Subsequent to the preliminary valuation of the non-cash components of the purchase consideration and net assets acquired, any adjustment identified associated with the purchase price allocation will be evaluated to determine whether the adjustment represents a measurement period adjustment in accordance with GAAP. If the adjustment is deemed to be a measurement period adjustment and is identified within one year of the acquisition, then the measurement period adjustment will be recorded in the current reporting period with a corresponding adjustment to the gain on bargain purchase.

Contingent Consideration

Contingent consideration in a business combination is recorded at fair value on the date of the acquisition and remeasured each subsequent reporting period with changes in fair value recognized in earnings. The purchase consideration in the NORCAL acquisition included contingent consideration with an acquisition date fair value of approximately $24 million. NORCAL policyholders who tendered NORCAL stock to ProAssurance are eligible for a share of contingent consideration in an amount of up to approximately $84 million depending upon the after-tax development of NORCAL's ultimate net losses between December 31, 2020 and December 31, 2023. The estimated fair value of this contingent consideration was $24 million as of December 31, 2021, which did not change from the acquisition date of May 5, 2021, and was derived utilizing a stochastic model. This estimate does not guarantee that contingent consideration will ultimately be paid. Depending on NORCAL's actual ultimate net loss development between December 31, 2020 and December 31, 2023, the actual amount due to eligible policyholders may be greater than or less than the $24 million current fair value estimate. See further discussion around the contingent consideration in Note 2 and Note 11 of the Notes to Consolidated Financial Statements.

VOBA

VOBA is an intangible asset (or liability) that reflects the estimated fair value of in-force contracts acquired in an acquisition and represents the portion of the purchase price that is allocated to the value of the right to receive future cash flows from the business in-force at the acquisition date. VOBA is based on actuarially determined projections, and in instances where the in-force business is expected to generate an underwriting loss, the value of VOBA may be negative. Negative VOBA is reported in the reserve for losses and loss adjustment expenses on the Consolidated Balance Sheets.

We recognized negative VOBA of $11.7 million in connection with our acquisition of NORCAL, representing the value of future losses expected to be recognized over the lifetime of the contracts acquired determined using a discount rate and other relevant assumptions. The negative VOBA will be amortized over a period in proportion to the earn-out of the premium as a reduction to current accident year net losses and loss adjustment expenses on the Consolidated Statements of Income and Comprehensive Income. See Note 2 of the Notes to Consolidated Financial Statements for more information.

Gain on Bargain Purchase

As a result of the NORCAL acquisition, we recognized a preliminary gain on bargain purchase of $74.4 million during the second quarter of 2021 representing the excess of the fair value of the identifiable assets acquired and liabilities assumed over the purchase consideration. A gain on bargain purchase is recognized in earnings and is considered unusual, infrequent and non-recurring in nature. We exclude gains on bargain purchases from Non-GAAP operating income (loss) as they do not reflect normal operating results. See further discussion around the gain on bargain purchase recognized in the second quarter of 2021 from the NORCAL acquisition in Note 2 of the Notes to Consolidated Financial Statements.

Accounting Changes

We did not have any change in accounting estimate or policy that had a material effect on our results of operations or financial position during 2021. We are not aware of any accounting changes not yet adopted as of December 31, 2021 that could have a material effect on our results of operations, financial position or cash flows.

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Liquidity and Capital Resources and Financial Condition

Overview

ProAssurance Corporation is a holding company and is a legal entity separate and distinct from its subsidiaries. As a holding company, our principal source of external revenue is our investment revenues. In addition, dividends from our operating subsidiaries represent another source of funds for our obligations, including debt service and shareholder dividends. We also charge our operating subsidiaries within our Specialty P&C (excluding the acquired operating subsidiaries of NORCAL) and Workers' Compensation Insurance segments a management fee based on the extent to which services are provided to the subsidiary and the amount of gross premium written by the subsidiary. At December 31, 2021, we held cash and liquid investments of approximately $73 million outside our insurance subsidiaries that were available for use without regulatory approval or other restriction. We also have $250 million in permitted borrowings available under our Revolving Credit Agreement as well as the possibility of a $50 million accordion feature, if successfully subscribed. As of February 17, 2022, no borrowings were outstanding under our Revolving Credit Agreement.

During 2021, our operating subsidiaries paid dividends to us of approximately $51 million. In the aggregate, our insurance subsidiaries are permitted to pay dividends of approximately $147 million over the course of 2022 without prior approval of state insurance regulators. However, the payment of any dividend requires prior notice to the insurance regulator in the state of domicile, and the regulator may reduce or prevent the dividend if, in its judgment, payment of the dividend would have an adverse effect on the surplus of the insurance subsidiary. We make the decision to pay dividends from an insurance subsidiary based on the capital needs of that subsidiary and may pay less than the permitted dividend or may also request permission to pay an additional amount (an extraordinary dividend).

Cash Flows

Cash flows between periods compare as follows:

Year Ended December 31
(In thousands)20212020Change
Net cash provided (used) by:
Operating activities$73,970$92,343$(18,373)
Investing activities(85,526)(8,484)(77,042)
Financing activities(60,624)(43,446)(17,178)
Increase (decrease) in cash and cash equivalents$(72,180)$40,413$(112,593)
Year Ended December 31
(In thousands)20202019Change
Net cash provided (used) by:
Operating activities$92,343$148,166$(55,823)
Investing activities(8,484)50,522(59,006)
Financing activities(43,446)(103,790)60,344
Increase (decrease) in cash and cash equivalents$40,413$94,898$(54,485)

The principal components of our operating cash flows are the excess of premiums collected and net investment income over losses paid and operating costs, including income taxes. Timing delays exist between the collection of premiums and the payment of losses associated with the premiums. Premiums are generally collected within the twelve-month period after the policy is written, while our claim payments are generally paid over a more extended period of time. Likewise, timing delays exist between the payment of claims and the collection of any associated reinsurance recoveries.

The decrease in operating cash flows of $18.4 million in 2021 as compared to 2020 was partially offset by additional net cash receipt from NORCAL of approximately $27.7 million primarily associated with net premium receipts, partially offset by transaction-related expenses. Excluding NORCAL, operating cash flows decreased by $46.1 million in 2021 as compared to 2020 primarily due to a decrease in net premium receipts of $61.9 million driven by our Lloyd's Syndicates and Specialty P&C segments. The decrease in premium receipts in our Lloyd's Syndicates segment reflected our decreased participation in the results of Syndicate 1729 and Syndicate 6131 for the 2021 underwriting year. The decrease in premium receipts in our Specialty P&C segment was due to our re-underwriting efforts, the dissolution of our arrangement with CAPAssurance and the effect of $14.3 million of tail premium received from a large national healthcare account during the second quarter of 2020 (see further discussion in our Segment Operating Results - Specialty Property & Casualty section that follows). Additionally, the decrease in operating cash flows was due to a decrease in cash received from investment income of $14.6 million driven by a

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decrease in distributed earnings and redemptions from our portfolio of investments in LPs/LLCs. Furthermore, the decrease in operating cash flows reflected the prior year effect of an increase in net cash received of $6.8 million associated with the cash settlement of a quota share reinsurance agreement between our Specialty P&C segment and one of its reinsurers in 2020. The decrease in operating cash flows was partially offset by a decrease in paid losses of $21.8 million driven by our Specialty P&C and Segregated Portfolio Cell Reinsurance segments. The decrease in paid losses in our Specialty P&C segment was primarily due to a smaller number of claims resolved with large indemnity payments as compared to the prior year period, some of which is likely associated with the COVID-19 pandemic including the disruption of the court systems. The decrease in paid losses in our Segregated Portfolio Cell Reinsurance segment reflected the effect of the payment of a $10 million claim during the first quarter of 2020 by an SPC at Eastern Re in which we do not participate. This claim payment related to a reserve established by the SPC in 2019 related to an errors and omissions liability policy. Additionally, the decrease in operating cash flows was partially offset by a decrease in cash paid for operating expenses of $7.6 million driven by the effect of one-time expenses of $5.4 million primarily related to employee severance and early retirement benefits paid to certain employees during the third quarter of 2020 and, to a lesser extent, a decrease in premium taxes due to a lower volume of premium written. In addition, the decrease in cash paid for operating expenses was due to our decreased participation in the results of Syndicate 1729 and Syndicate 6131 for the 2021 underwriting year. The remaining variance in operating cash flows in 2021 as compared to 2020 was comprised of individually insignificant components.

The decrease in operating cash flows in 2020 as compared to 2019 of $55.8 million was primarily due to an increase in paid losses of $89.1 million driven by our Specialty P&C and Segregated Portfolio Cell Reinsurance segments. The increase in paid losses in our Specialty P&C segment was primarily due to higher average claim payments. The increase in paid losses in our Segregated Portfolio Cell Reinsurance segment reflected the aforementioned payment of a $10 million claim during the first quarter of 2020. Furthermore, the decrease in operating cash flows reflected a decrease in net cash received of $7.4 million associated with the cash settlement of the 2017 calendar year quota share reinsurance agreement between our Specialty P&C segment and Syndicate 1729 due to the reduction in premiums ceded to Syndicate 1729. The decrease in operating cash flows also reflected the aforementioned one-time expenses of $5.4 million. Additionally, the decrease in operating cash flows reflected a decrease in cash received from investment income of $3.5 million primarily due to a reduction in dividends received on our equity portfolio resulting from a decrease in our allocation to this asset category. The decrease in operating cash flows was somewhat offset by an increase in net premium receipts of $28.1 million and a decrease in 2020 net tax payments as compared to 2019 of $9.8 million. The increase in net premium receipts was driven by our Specialty P&C segment due to $14.3 million of tail premium, as previously discussed. The decrease in net tax payments was primarily due to refunds received in 2020. Furthermore, the decrease in operating cash flows was partially offset by an increase in net cash received of $6.8 million associated with the cash settlement of a quota share reinsurance agreement, as previously discussed. The remaining variance in operating cash flows in 2020 as compared to 2019 was comprised of individually insignificant components.

We manage our investing cash flows to ensure that we will have sufficient liquidity to meet our obligations, taking into consideration the timing of cash flows from our investments, including interest payments, dividends and principal payments, as well as the expected cash flows to be generated by our operations as discussed in this section under the heading "Investing Activities and Related Cash Flows."

Our financing cash flows are primarily comprised of dividend payments and borrowings and repayments under our Revolving Credit Agreement. See further discussion of our financing activities in this section under the heading "Financing Activities and Related Cash Flows."

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Operating Activities and Related Cash Flows

Losses

The following table, known as the Analysis of Reserve Development, presents information over the preceding ten years regarding the payment of our losses as well as changes to (the development of) our estimates of losses during that time period. As noted in the table, we have completed various acquisitions over the ten year period which have affected original and re-estimated gross and net reserve balances as well as loss payments.

The table includes losses on both a direct and an assumed basis and is net of anticipated reinsurance recoverables. The gross liability for losses before reinsurance, as shown on the balance sheet, and the reconciliation of that gross liability to amounts net of reinsurance are reflected below the table. We do not discount our reserve for losses to present value. Information presented in the table is cumulative and, accordingly, each amount includes the effects of all changes in amounts for prior years. The table presents the development of our balance sheet reserve for losses; it does not present accident year or policy year development data. Conditions and trends that have affected the development of liabilities in the past may not necessarily occur in the future. Accordingly, it is not appropriate to extrapolate future redundancies or deficiencies based on this table.

The following may be helpful in understanding the Analysis of Reserve Development:

•The line entitled “Reserve for losses, undiscounted and net of reinsurance recoverables” reflects our reserve for losses and loss adjustment expense, less the receivables from reinsurers, each as reported in our Consolidated Balance Sheets at the end of each year (the Balance Sheet Reserves).

•The section entitled “Cumulative net paid, as of” reflects the cumulative amounts paid as of the end of each succeeding year with respect to the previously recorded Balance Sheet Reserves.

•The section entitled “Re-estimated net liability as of” reflects the re-estimated amount of the liability previously recorded as Balance Sheet Reserves that includes the cumulative amounts paid and an estimate of the remaining net liability based upon claims experience as of the end of each succeeding year (the Net Re-estimated Liability).

•The line entitled “Net cumulative redundancy (deficiency)” reflects the difference between the previously recorded Balance Sheet Reserve for each applicable year and the Net Re-estimated Liability relating thereto as of the end of the most recent fiscal year.

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Analysis of Reserve Development
December 31
(In thousands)20112012201320142015201620172018201920202021
Reserve for losses, undiscounted and net of reinsurance recoverables$2,000,114$1,860,076$1,825,304$1,820,300$1,755,976$1,719,953$1,712,796$1,776,027$1,955,818$2,032,092$3,128,199
Cumulative net paid, as of:
One Year Later300,703311,835343,197390,849383,062369,682412,711458,991501,969499,369
Two Years Later526,903563,805571,690646,878633,246644,422704,830787,223839,117
Three Years Later682,576704,795732,892804,624818,102824,686900,4211,007,970
Four Years Later763,703800,189826,384917,236918,403958,7351,041,817
Five Years Later821,742852,873891,615971,392994,7711,035,280
Six Years Later852,119893,529924,3341,012,9751,039,669
Seven Years Later876,840915,730952,1181,037,853
Eight Years Later891,820930,375967,945
Nine Years Later899,969941,468
Ten Years Later911,079
Re-estimated net liability as of:
End of Year2,000,1141,860,0761,825,3041,820,3001,755,9761,719,9531,712,7961,776,0271,955,8182,032,092
One Year Later1,728,0761,644,2031,644,5161,659,1201,612,1981,585,5931,620,6801,764,2441,905,4191,994,516
Two Years Later1,498,1581,472,2591,483,3781,519,0781,485,3571,481,2921,541,2371,716,0961,882,368
Three Years Later1,342,9961,331,8281,358,5601,396,1301,380,6871,373,1451,501,1381,706,893
Four Years Later1,224,5971,231,3371,252,6051,296,0741,279,8771,340,1911,488,345
Five Years Later1,148,7931,157,4931,173,9751,228,4801,253,2451,333,861
Six Years Later1,091,6461,108,7161,126,3081,211,7061,252,096
Seven Years Later1,056,0531,078,0571,121,0871,206,875
Eight Years Later1,034,6901,075,2771,119,984
Nine Years Later1,033,4351,070,161
Ten Years Later1,031,800
Net cumulative redundancy (deficiency)$968,314$789,915$705,320$613,425$503,880$386,092$224,451$69,134$73,450$37,576
Original gross liability - end of year$2,247,772$2,051,428$2,072,822$2,058,266$2,005,326$1,993,428$2,048,381$2,119,847$2,346,526$2,417,179
Reinsurance recoverables(247,658)(191,352)(247,518)(237,966)(249,350)(273,475)(335,585)(343,820)(390,708)(385,087)
Original net liability - end of year$2,000,114$1,860,076$1,825,304$1,820,300$1,755,976$1,719,953$1,712,796$1,776,027$1,955,818$2,032,092
Gross re-estimated liability - latest$1,158,598$1,191,990$1,262,035$1,365,348$1,449,275$1,573,230$1,800,829$2,021,075$2,212,946$2,346,497
Re-estimated reinsurance recoverables(126,798)(121,829)(142,051)(158,473)(197,179)(239,369)(312,484)(314,182)(330,578)(351,981)
Net re-estimated liability - latest$1,031,800$1,070,161$1,119,984$1,206,875$1,252,096$1,333,861$1,488,345$1,706,893$1,882,368$1,994,516
Gross cumulative redundancy (deficiency)$1,089,174$859,438$810,787$692,918$556,051$420,198$247,552$98,772$133,580$70,682

See table notes on following page.

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Table Notes

•We have elected to present reserve history for acquired entities on a prospective basis in the table above; therefore, certain items will not agree to the following table which details activity in our net reserve for losses.

•Reserves for 2012 and thereafter include gross and net reserves acquired in 2012 business combinations of $21.8 million and $19.2 million, respectively, which considers reductions of $3.6 million and $3.3 million, respectively, recorded in 2013 due to the re-estimation of the fair value of the acquired reserves.

•Reserves for 2013 include gross and net reserves acquired in 2013 business combinations of $201.1 million and $126.0 million, respectively.

•Reserves for 2014 include gross and net reserves acquired in 2014 business combinations of $153.2 million and $139.5 million, respectively.

•Reserves for 2021 include gross and net reserves acquired in 2021 business combinations of $1.2 billion and $1.1 billion, respectively.

In each year reflected in the table, we have estimated our reserve for losses utilizing the management and actuarial processes discussed under the heading "Reserve for Losses and Loss Adjustment Expenses" in the Critical Accounting Estimates section. Factors that have contributed to the variation in loss development are primarily related to the extended period of time required to resolve professional liability claims and include the following:

•The HCPL legal environment deteriorated in the late 1990’s and severity began to increase at a greater pace than anticipated in our rates and reserve estimates. We addressed the adverse severity trends through increased rates, stricter underwriting and modifications to claims handling procedures, and reflected this adverse severity trend when we established our initial reserves for subsequent years.

•These adverse severity trends later moderated, with that moderation becoming more pronounced beginning in 2009. We were cautious in giving full recognition to indications that the pace of severity increase had slowed, however we gave measured recognition of the improved trend in our reserve estimates. The favorable development was most pronounced for years 2004 to 2008, as the initial reserves for these accident years were established prior to substantial indication that severity trends were moderating. We gave stronger recognition to the lower severity trend as time elapsed and a greater percentage of claims were closed.

•A general decline in claims frequency has also been a contributor to favorable loss development. A significant portion of our policies through 2003 were issued on an occurrence basis, and a smaller portion of our ongoing business results from the issuance of extended reporting endorsements which have occurrence-like exposure. As claims frequency declined, the number of reported claims related to these coverages was less than originally expected.

•Beginning in 2017, we identified potential higher severity trends in the broader HCPL industry. These trends were also reflected in increases in estimates of ultimate losses for open HCPL claims for earlier accident years, which resulted in a lower amount of favorable development recognized in 2018 and 2017 as compared to prior years.

•During 2019 the loss experience in our Specialty line of business deteriorated further, particularly in regard to the reserves we established for a large national healthcare account that experienced losses far exceeding the assumptions we made when underwriting the account, beginning in 2016. As a result, we strengthened our Specialty reserves through the recognition of net unfavorable development on prior accident years and a higher current accident year net loss ratio in our Specialty P&C segment in 2019.

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Activity in our net reserve for losses during 2021, 2020 and 2019 is summarized below:

Year Ended December 31
(In thousands)202120202019
Balance, beginning of year$2,417,179$2,346,526$2,119,847
Less reinsurance recoverables on unpaid losses and loss adjustment expenses385,087390,708343,820
Net balance, beginning of year2,032,0921,955,8181,776,027
Net reserves acquired from acquisitions1,089,103
Net losses:
Current year(1)(2)(3)797,732711,846765,698
Favorable development of reserves established in prior years, net(3)(45,483)(50,399)(11,783)
Total752,249661,447753,915
Paid related to:
Current year(109,925)(83,204)(115,133)
Prior years(635,320)(501,969)(458,991)
Total paid(745,245)(585,173)(574,124)
Net balance, end of year3,128,1992,032,0921,955,818
Plus reinsurance recoverables on unpaid losses and loss adjustment expenses451,741385,087390,708
Balance, end of year$3,579,940$2,417,179$2,346,526

(1) Current year net losses for the year ended December 31, 2019 included incurred losses of $2.1 million related to a loss portfolio transfer entered into during 2019 in the Specialty P&C segment. In addition, current year net losses for the year ended December 31, 2019 included a PDR of $9.2 million associated with the unearned premium of a large national healthcare account's claims-made policy in the Specialty P&C segment. Current year net losses for the year ended December 31, 2020 included the amortization of the aforementioned $9.2 million PDR which offsets the impact of the losses incurred associated with the premium earned related to the large national healthcare account's claims-made policy.

(2) During 2020, the aforementioned large national healthcare account did not renew on terms offered by the Company and exercised its contractual option to purchase extended reporting endorsement or "tail" coverage. As a result, we recognized total current year losses of $60.0 million (assumes a full limit loss) within the Specialty P&C segment for the year ended December 31, 2021.

(3) Current year net losses and prior accident year development for the year ended December 31, 2021 includes certain purchase accounting adjustments associated with our acquisition of NORCAL. See Note 10 of the Notes to Consolidated Financial Statements for additional information.

At December 31, 2021 our gross reserve for losses included case reserves of approximately $2.1 billion and IBNR reserves of approximately $1.4 billion. Our consolidated gross reserve for losses on a GAAP basis exceeds the combined gross reserves of our insurance subsidiaries on a statutory basis by approximately $0.3 billion, which is principally due to the portion of the GAAP reserve for losses that is reflected for statutory accounting purposes as unearned premiums. These unearned premiums are applicable to extended reporting endorsements (“tail” coverage) issued without a premium charge upon death, disability or retirement of an insured who meets certain qualifications.

Reinsurance

Within our Specialty P&C segment, we use insurance and reinsurance (collectively, “reinsurance”) to provide capacity to write larger limits of liability, to provide reimbursement for losses incurred under the higher limit coverages we offer and to provide protection against losses in excess of policy limits. Within our Workers' Compensation Insurance segment, we use reinsurance to reduce our net liability on individual risks, to mitigate the effect of significant loss occurrences (including catastrophic events), to stabilize underwriting results and to increase underwriting capacity by decreasing leverage. In both our Specialty P&C and Workers' Compensation Insurance segments, we use reinsurance in risk sharing arrangements to align our objectives with those of our strategic business partners and to provide custom insurance solutions for large customer groups. Within our Lloyd's Syndicates segment, Syndicate 1729 utilizes reinsurance to provide capacity to write larger limits of liability on individual risks, to provide protection against catastrophic loss and to provide protection against losses in excess of policy limits. The purchase of reinsurance does not relieve us from the ultimate risk on our policies; however, it does provide reimbursement for certain losses we pay. We pay our reinsurers a premium in exchange for reinsurance of the risk. In certain of our excess of loss arrangements, the premium due to the reinsurer is determined by the loss experience of the business

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reinsured, subject to certain minimum and maximum amounts. Until all loss amounts are known, we estimate the premium due to the reinsurer. Changes to the estimate of premium owed under reinsurance agreements related to prior periods are recorded in the period in which the change in estimate occurs and can have a significant effect on net premiums earned.

We offer alternative market solutions whereby we cede certain premiums from our Workers' Compensation Insurance and Specialty P&C segments to either the SPCs at Inova Re or Eastern Re, our Cayman Islands reinsurance subsidiaries which are reported in our Segregated Portfolio Cell Reinsurance segment or, to a limited extent, an unaffiliated captive insurer for one program. The majority of these policies are reinsured to the SPCs at Inova Re or Eastern Re, net of a ceding commission. Each SPC at Inova Re and Eastern Re is owned, fully or in part, by an individual company, agency, group or association and the results of the SPCs are due to the participants of that cell. We participate to a varying degree in the results of selected SPCs and, for the SPCs in which we participate, our participation interest ranges from a low of 20% to a high of 85%. SPC results attributable to external cell participants are reported as an SPC dividend expense (income) in our Segregated Portfolio Cell Reinsurance segment. See further discussion on our SPC operations in the Segment Results - Segregated Portfolio Cell Reinsurance section that follows. The alternative market workers' compensation policies are ceded from our Workers' Compensation Insurance segment to the SPCs under 100% quota share reinsurance agreements. The alternative market healthcare professional liability policies are ceded from our Specialty P&C segment to the SPCs under either excess of loss or quota share reinsurance agreements, depending on the structure of the individual program. The portion of the risk that is not ceded to an SPC is retained in our Specialty P&C segment and may also be reinsured under our standard healthcare professional liability reinsurance program, depending on the policy limits provided. The remaining premium written in our alternative market business is 100% ceded to an unaffiliated captive insurer.

Excess of Loss Reinsurance Agreements

We generally reinsure risks under treaties (our excess of loss reinsurance agreements) pursuant to which the reinsurers agree to assume all or a portion of all risks that we insure above our individual risk retention levels, up to the maximum individual limits offered. Generally, these agreements are negotiated and renewed annually. Our HCPL and Medical Technology Liability treaties renew annually on October 1. As of October 1, 2021, our HCPL treaty renewed with a lower gross rate and also incorporated NORCAL policies. For the NORCAL excess of loss reinsurance arrangement in effect prior to October 1, 2021, NORCAL policies were reinsured under separate reinsurance agreements, primarily excess of loss, which have historically renewed annually on January 1. For the NORCAL excess of loss reinsurance arrangement that renewed on January 1, 2021, retention was generally the first $2 million in risk and coverages in excess of this amount are ceded up to $24 million. There were no significant changes in the cost or structure of our Medical Technology Liability treaty upon the latest renewal on October 1, 2021. Our Workers' Compensation treaty renews annually on May 1. Our traditional workers' compensation treaty renewed May 1, 2021 at a higher rate than the previous agreement, with an increase in the AAD to 3.50% from 3.16% of ceded earned premium, in excess of the $0.5 million retention per loss occurrence; all other material treaty terms were consistent with the expiring agreement. The significant coverages provided by our current excess of loss reinsurance agreements are detailed in the following table.

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Excess of Loss Reinsurance Agreements

Column 1Column 2Column 3Column 4Column 5Column 6
Healthcare Professional LiabilityMedical Technology & Life Sciences ProductsWorkers' Compensation - Traditional

(1) Effective October 1, 2020, one prepaid limit reinstatement of $21M and a second limit reinstatement of up to $21M for the second layer, subject to reinstatement premium, which attaches after the first reinstatement has been completely exhausted. All limit reinstatements thereafter require no additional premium. Effective October 1, 2021, limits can be reinstated a maximum of four times.

(2) Prior to October 1, 2020, retention was $1M.

(3) Historically, retention has ranged from 2.5% to 32.5%.

(4) Historically, retention has ranged from $1M to $2M.

(5) Includes an AAD where retention is 3.5% of subject earned premium in annual losses otherwise recoverable in excess of the $500K retention per loss occurrence.

Large HCPL risks that are above the limits of our basic reinsurance treaties may be reinsured on a facultative basis, whereby the reinsurer agrees to insure a particular risk up to a designated limit. We also have in place a number of risk sharing arrangements that apply to the first $1 million of losses for certain large healthcare systems and other insurance entities, as well as with certain insurance agencies that produce business for us.

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Other Reinsurance Arrangements

For the workers' compensation business ceded to Inova Re and Eastern Re, each SPC has in place its own reinsurance arrangements; which are illustrated in the following table.

Segregated Portfolio Cell Reinsurance

Column 1Column 2Column 3
Per Occurrence CoverageAggregate Coverage

(1) The attachment point is based on a percentage of written premium within individual cells, ranges from 85% to 94%, and varies by cell.

Each SPC has participants and the profit or loss of each cell accrues fully to these cell participants. As previously discussed, we participate in certain SPCs to a varying degree. Each SPC maintains a loss fund initially equal to the difference between premium assumed by the cell and the ceding commission. The external participants of each cell provide collateral to us, typically in the form of a letter of credit that is initially equal to the difference between the loss fund of the SPC (amount of funds available to pay losses after deduction of ceding commission) and the aggregate attachment point of the reinsurance. Over time, an SPC's retained profits are considered in the determination of the collateral amount required to be provided by the cell's external participants.

Within our Lloyd's Syndicates segment, Syndicate 1729 utilizes reinsurance to provide capacity to write larger limits of liability on individual risks, to provide protection against catastrophic loss and to provide protection against losses in excess of policy limits. The level of reinsurance that Syndicate 1729 purchases is dependent on a number of factors, including its underwriting risk appetite for catastrophic exposure, the specific risks inherent in each line or class of business written and the pricing, coverage and terms and conditions available from the reinsurance market. Reinsurance protection by line of business is as follows:

•Reinsurance is utilized on a per risk basis for the property insurance and casualty coverages in order to mitigate risk volatility.

•Catastrophic protection is utilized on both our property insurance and casualty coverages to protect against losses in excess of policy limits as well as natural catastrophes.

•Both quota share reinsurance and excess of loss reinsurance are utilized to manage the net loss exposure on our property reinsurance coverages.

•Property umbrella excess of loss reinsurance is utilized for peak catastrophe and frequency of catastrophe exposures.

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•Prior to January 1, 2022, external excess of loss reinsurance was utilized by Syndicate 1729 to manage the net loss exposure on the specialty property and contingency coverages ceded to Syndicate 6131; Syndicate 6131 ceased underwriting on a quota share basis with Syndicate 1729 as Syndicate 6131's business was incorporated into Syndicate 1729 beginning with the 2022 year of account. For the second half of 2020, external quota share reinsurance was utilized by Syndicate 6131 to manage the net loss exposure on the specialty property and contingency coverages it assumed from Syndicate 1729 by ceding essentially half of the premium assumed to an unaffiliated insurer; this agreement was non-renewed on January 1, 2021 (see further discussion in the Segment Results - Lloyd's Syndicates section that follows).

Syndicate 1729 may still be exposed to losses that exceed the level of reinsurance purchased as well as to reinstatement premiums triggered by losses exceeding specified levels. Cash demands on Syndicate 1729 can vary significantly depending on the nature and intensity of a loss event. For significant reinsured catastrophe losses, the inability or unwillingness of the reinsurer to make timely payments under the terms of the reinsurance agreement could have an adverse effect on Syndicate 1729's liquidity.

Taxes

We are subject to the tax laws and regulations of the U.S., Cayman Islands and U.K. We file a consolidated U.S. federal income tax return that includes the parent company and its U.S. subsidiaries, except for ProAssurance American Mutual, a Risk Retention Group. Our filing obligations include a requirement to make quarterly payments of estimated taxes to the IRS using the corporate tax rate effective for the tax year. We did not make any quarterly estimated tax payments during the year ended December 31, 2021 or 2020.

As a result of the CARES Act that was signed into law on March 27, 2020, as previously discussed, we were permitted to carryback NOLs generated in tax years 2019 and 2020 for up to five years. See further discussion in Note 7 of the Notes to Consolidated Financial Statements. We generated an NOL of approximately $33.3 million from the 2020 tax year that was carried back to the 2015 tax year that resulted in a claim for a refund of approximately $11.7 million, which we anticipate to receive during the first half of 2022. Additionally, we had an NOL of approximately $25.6 million from the 2019 tax year which was carried back to the 2014 tax year and generated a tax refund of approximately $9.0 million which we received in February 2021. Furthermore, we received a tax refund of $1.3 million during the second quarter of 2021 due to the repeal of a previous election we made under the TCJA related to discounted loss reserves.

As a result of our acquisition of NORCAL, we recorded $46.8 million of net deferred tax assets reflecting the remeasurement of NORCAL's historical net deferred tax assets. The net deferred tax assets acquired from NORCAL were subject to recalculation following application of all purchase accounting adjustments and our assessment of the realizability of NORCAL's deferred tax assets. As a result of the NORCAL acquisition, we have U.S. federal NOL carryforwards which as of December 31, 2021 were approximately $43.0 million. These NOL carryforwards are subject to limitation by Internal Revenue Code Section 382 and will begin to expire in 2035.

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Investing Activities and Related Cash Flows

Our investments at December 31, 2021 and December 31, 2020 are comprised as follows:

December 31, 2021December 31, 2020
($ in thousands)Carrying Value% of Total InvestmentCarrying Value% of Total Investment
Fixed maturities, available for sale:
U.S. Treasury obligations$238,5075%$107,0593%
U.S. Government-sponsored enterprise obligations20,2341%12,2611%
State and municipal bonds519,19611%332,92010%
Corporate debt1,898,55639%1,329,34239%
Residential mortgage-backed securities453,9419%276,5418%
Commercial mortgage-backed securities245,6245%126,4024%
Other asset-backed securities457,6649%273,0068%
Total fixed maturities, available-for-sale3,833,72279%2,457,53173%
Fixed maturities, trading43,6701%48,4561%
Total fixed maturities3,877,39280%2,505,98774%
Equity investments(1)214,8074%120,1014%
Short-term investments216,9874%337,81310%
BOLI81,7672%67,8472%
Investment in unconsolidated subsidiaries335,5767%310,5299%
Other investments101,7943%47,0681%
Total investments$4,828,323100%$3,389,345100%
(1)Includes $187.1 million and $69.5 million of investment grade bond funds which are not subject to significant equity price risk for the years ended December 31, 2021 and 2020, respectively.

At December 31, 2021, 100% of our investments in available-for-sale fixed maturity securities were rated and the average rating was A+. The distribution of our investments in available-for-sale fixed maturity securities by rating were as follows:

December 31, 2021December 31, 2020
($ in thousands)Carrying Value% of Total InvestmentCarrying Value% of Total Investment
Rating*
AAA$1,129,13629%$717,18729%
AA+130,0773%103,9964%
AA254,5707%168,4527%
AA-194,6615%122,7335%
A+221,4736%197,2748%
A521,59814%323,04413%
A-364,1479%245,46410%
BBB+292,9848%189,9718%
BBB300,6508%190,3858%
BBB-127,9823%59,8472%
Below investment grade296,4448%133,6075%
Not rated%5,5711%
Total$3,833,722100%$2,457,531100%
*Average of three NRSRO sources, presented as an S&P equivalent. Source: S&P, Copyright ©2021, S&P Global Market Intelligence

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Our acquisition of NORCAL added the following to our investment holdings as of May 5, 2021, the date of acquisition:

(In thousands)
Fixed maturities, available for sale$1,100,058
Equity investments374,484
Short-term investments61,289
BOLI12,581
Investment in unconsolidated subsidiaries26,948
Other investments32,461
Total investments$1,607,821

A detailed listing of our investment holdings as of December 31, 2021 is located under the Financial Information heading on the Investor Relations page of our website which can be reached directly at https://investor.proassurance.com/financial-information/quarterly-investment-supplements/default.aspx or through links from the Investor Relations section of our website, investor.proassurance.com.

We manage our investments to ensure that we will have sufficient liquidity to meet our obligations, taking into consideration the timing of cash flows from our investments, including interest payments, dividends and principal payments, as well as the expected cash flows to be generated by our operations. Furthermore, we managed our investments as part of our capital planning in anticipation of closing our acquisition of NORCAL. In addition to the interest and dividends we will receive from our investments, we anticipate that between $70 million and $130 million of our portfolio will mature (or be paid down) each quarter over the next twelve months and become available, if needed, to meet our cash flow requirements. The primary outflow of cash at our insurance subsidiaries is related to paid losses and operating costs, including income taxes. The payment of individual claims cannot be predicted with certainty; therefore, we rely upon the history of paid claims in estimating the timing of future claims payments with consideration to current and anticipated industry trends and macroeconomic conditions. To the extent that we may have an unanticipated shortfall in cash, we may either liquidate securities or borrow funds under existing borrowing arrangements through our Revolving Credit Agreement and the FHLB system. Permitted borrowings under our Revolving Credit Agreement are $250 million with the possibility of an additional $50 million accordion feature, if successfully subscribed. Given the duration of our investments, we do not foresee a shortfall that would require us to meet operating cash needs through additional borrowings. Additional information regarding our Revolving Credit Agreement is detailed in Note 13 of the Notes to Consolidated Financial Statements.

At December 31, 2021, our FAL was comprised of fixed maturity securities with a fair value of $36.6 million and cash and cash equivalents of $1.2 million deposited with Lloyd's. See further discussion in Note 4 of the Notes to Consolidated Financial Statements. During the second and fourth quarters of 2021, we received a return of approximately $24.5 million and $8.0 million, respectively, of cash from our FAL balances given the reduction in our participation in the results of Syndicate 1729 and Syndicate 6131 for the 2021 underwriting year. Further, during the fourth quarter of 2021, ProAssurance received a return of approximately $26.6 million of cash from our FAL balances given Syndicate 6131 ceased underwriting on a quota share basis with Syndicate 1729 as Syndicate 6131's business is retained within Syndicate 1729 beginning with the 2022 underwriting year. See further discussion on the return of FAL in the Segment Results - Lloyd's Syndicates section that follows.

Our investment portfolio continues to be primarily composed of high quality fixed income securities with approximately 92% of our fixed maturities being investment grade securities as determined by national rating agencies. The weighted average effective duration of our fixed maturity securities at December 31, 2021 was 3.71 years; the weighted average effective duration of our fixed maturity securities combined with our short-term securities was 3.51 years.

The carrying value and unfunded commitments for certain of our investments were as follows:

Carrying ValueDecember 31, 2021
($ in thousands, except expected funding period)December 31, 2021December 31, 2020Unfunded CommitmentExpected funding period in years
Qualified affordable housing project tax credit partnerships (1)$12,424$27,719$5815
All other investments, primarily investment fund LPs/LLCs323,152282,810168,3794
Total$335,576$310,529$168,960
(1) The carrying value reflects our total commitments (both funded and unfunded) to the partnerships, less any amortization, since our initial investment. We fund these investments based on funding schedules maintained by the partnerships.

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Investment fund LPs/LLCs are by nature less liquid and may involve more risk than other investments. We manage our risk through diversification of asset class and geographic location. At December 31, 2021, we had investments in 34 separate investment funds with a total carrying value of $323.2 million which represented approximately 7% of our total investments. Our investment fund LPs/LLCs generate earnings from trading portfolios, secured debt, debt securities, multi-strategy funds and private equity investments, and the performance of these LPs/LLCs is affected by the volatility of equity and credit markets. For our investments in LPs/LLCs, we record our allocable portion of the partnership operating income or loss as the results of the LPs/LLCs become available, typically following the end of a reporting period.

Business Combinations and Ventures

On May 5, 2021, we completed the acquisition of NORCAL by purchasing 98.8% of the converted company stock in exchange for total consideration transferred of $449 million. On September 16, 2021, we acquired the remaining 1.2% interest in NORCAL for $3 million of cash. On May 5, 2021, ProAssurance funded the transaction with $248 million of cash on hand and NORCAL paid $2 million to policyholders who elected to receive the discounted cash option for their allocated share of the converted company's equity. Additional consideration with a principal amount of $191 million and a fair value of $175 million, is in the form of Contribution Certificates issued to certain NORCAL policyholders in the conversion, and those instruments are an obligation of NORCAL Insurance Company, the successor of NORCAL Mutual Insurance Company (see Note 13 of the Notes to Consolidated Financial Statements for further discussion of the terms of the Contribution Certificates). Policyholders who tendered NORCAL stock to ProAssurance are also eligible for a share of contingent consideration in an amount of up to approximately $84 million depending upon the after-tax development of NORCAL's ultimate net losses between December 31, 2020 and December 31, 2023. The estimated fair value of this contingent consideration was $24 million as of May 5, 2021 and December 31, 2021. The Agreement and Plan of Acquisition is included as Exhibit 2.1 of this report. Additional information regarding our acquisition of NORCAL is included in Note 2 of the Notes to Consolidated Financial Statements. There were no business combinations during the year ended December 31, 2020.

Financing Activities and Related Cash Flows

Treasury Shares

Treasury share activity for 2021, 2020 and 2019 was as follows:

(In thousands)202120202019
Treasury shares at the beginning of the period9,3259,3259,352
Shares reissued, primarily those reissued pursuant to the ProAssurance 2011 Employee Stock Ownership Plan, had a fair value of approximately $1 million in 2019(27)
Treasury shares at the end of the period9,3259,3259,325

We did not repurchase any common shares subsequent to December 31, 2021 and as of February 17, 2022 our remaining Board authorization was approximately $110 million.

ProAssurance Shareholder Dividends

Our Board declared cash dividends during 2021, 2020 and 2019 as follows:

Quarterly Cash Dividends Declared, per Share
202120202019
First Quarter$0.05$0.31$0.31
Second Quarter$0.05$0.05$0.31
Third Quarter$0.05$0.05$0.31
Fourth Quarter$0.05$0.05$0.31

Each dividend was paid in the month following the quarter in which it was declared. Cash dividends totaling $11 million, $39 million and $93 million were paid during the years ended December 31, 2021, 2020 and 2019, respectively. Any decision to pay future cash dividends is subject to the Board’s final determination after a comprehensive review of financial performance, future expectations and other factors deemed relevant by the Board.

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Debt

At December 31, 2021, our debt included $250 million of outstanding unsecured senior notes. The notes bear interest at 5.3% annually and are due in 2023 although they may be redeemed in whole or part prior to maturity. There are no financial covenants associated with these notes.

NORCAL Insurance Company, successor to NORCAL Mutual Insurance Company, issued Contribution Certificates, which bear interest at 3.0% annually and are due in 2031, to certain NORCAL policyholders in the conversion. The Contribution Certificates have a principal amount of $191 million and were recorded at their fair value of $175 million at the date of the NORCAL acquisition. The difference of $16 million between the recorded acquisition date fair value and the principal balance of the Contribution Certificates will be accreted utilizing the effective interest method over the term of the certificates of ten years as an increase to interest expense. Furthermore, interest payments, which begin in April 2022, are subject to deferral if we do not receive permission from the California Department of Insurance prior to payment. See Note 2 and Note 13 of the Notes to Consolidated Financial Statements for additional information on the Contribution Certificates issued in the NORCAL acquisition. There are no financial covenants associated with these certificates.

We have a Revolving Credit Agreement, which expires in November 2024, that may be used for general corporate purposes, including, but not limited to, short-term working capital, share repurchases as authorized by the Board and support for other activities. Our Revolving Credit Agreement permits borrowings of up to $250 million as well as the possibility of a $50 million accordion feature, if successfully subscribed. At December 31, 2021, there were no outstanding borrowings on our Revolving Credit Agreement; we are in compliance with the financial covenants of the Revolving Credit Agreement.

Two of our subsidiaries, ProAssurance Indemnity Company, Inc. and ProAssurance Insurance Company of America, had Mortgage Loans with one lender in connection with the recapitalization of two office buildings, with scheduled maturities in December 2027. The Mortgage Loans accrued interest at three-month LIBOR plus 1.325% with principal and interest payable on a quarterly basis. During 2021, we repaid the balance outstanding on the Mortgage Loans of approximately $35.3 million. Interest expense on the Mortgage Loans during the year ended December 31, 2021 included the write-off of the unamortized debt issuance costs which were nominal in amount.

Additional information regarding our debt is provided in Note 13 of the Notes to Consolidated Financial Statements.

Three of our insurance subsidiaries are members of an FHLB. Through membership, those subsidiaries have access to secured cash advances which can be used for liquidity purposes or other operational needs. In order for us to use FHLB proceeds, regulatory approvals may be required depending on the nature of the transaction. To date, those subsidiaries have not materially utilized their membership for borrowing purposes.

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Results of Operations - Year Ended December 31, 2021 Compared to Year Ended December 31, 2020

Selected consolidated financial data for each period is summarized in the table below.

Year Ended December 31
($ in thousands, except per share data)20212020Change
Revenues:
Net premiums written$882,721$747,701$135,020
Net premiums earned$971,668$792,715$178,953
Net investment result119,49660,07759,419
Net investment gains (losses)24,31015,6788,632
Other income8,9366,4702,466
Total revenues1,124,410874,940249,470
Expenses:
Net losses and loss adjustment expenses752,249661,44790,802
Underwriting, policy acquisition and operating expenses268,246237,88130,365
SPC U.S. federal income tax expense1,9471,746201
SPC dividend expense (income)10,05014,304(4,254)
Interest expense19,71915,5034,216
Goodwill impairment161,115(161,115)
Total expenses1,052,2111,091,996(39,785)
Gain on bargain purchase74,40874,408
Income (loss) before income taxes146,607(217,056)363,663
Income tax expense (benefit)2,483(41,329)43,812
Net income (loss)$144,124$(175,727)$319,851
Non-GAAP operating income (loss)$75,892$(27,741)$103,633
Earnings (loss) per share:
Basic$2.67$(3.26)$5.93
Diluted$2.67$(3.26)$5.93
Non-GAAP operating income (loss) per share:
Basic$1.41$(0.52)$1.93
Diluted$1.40$(0.52)$1.92
Net loss ratio77.4%83.4%(6.0 pts)
Underwriting expense ratio27.6%30.0%(2.4 pts)
Combined ratio105.0%113.4%(8.4 pts)
Operating ratio97.7%104.3%(6.6 pts)
Effective tax rate1.7%19.0%(17.3 pts)
Return on equity*5.3%(12.3%)17.6 pts
*See further discussion on this calculation in the Executive Summary of Operations section under the heading "ROE."
In all tables that follow, the abbreviation "nm" indicates that the information or the percentage change is not meaningful.

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Executive Summary of Operations

The following sections provide an overview of our consolidated and segment results of operations for the year ended December 31, 2021 as compared to the year ended December 31, 2020. See the Segment Results sections that follow for additional information regarding each segment's results. For a full discussion of the changes in the financial condition, results of operations and cash flows for the year ended December 31, 2020 as compared to the year ended December 31, 2019, please refer to Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" section of ProAssurance's December 31, 2020 report on Form 10-K.

Revenues

The following table shows our consolidated and segment net premiums earned:

Year Ended December 31
($ in thousands)20212020Change
Net Premiums Earned
Specialty P&C$695,008$477,365$217,64345.6%
Workers' Compensation Insurance164,600171,772(7,172)(4.2%)
Segregated Portfolio Cell Reinsurance63,68866,352(2,664)(4.0%)
Lloyd's Syndicates48,37277,226(28,854)(37.4%)
Consolidated total$971,668$792,715$178,95322.6%

For the year ended December 31, 2021, consolidated net premiums earned included additional earned premiums of $214.6 million in our Specialty P&C segment from our acquisition of NORCAL. Excluding NORCAL, consolidated net premiums earned decreased $35.6 million in 2021 as compared to 2020 driven by a decrease in net premiums earned in our Lloyd's Syndicates and Workers' Compensation Insurance segments, partially offset by an increase in net premiums earned in our Specialty P&C segment. The decrease in our Lloyd's Syndicates segment was due to our decreased participation in the results of Syndicate 1729 and Syndicate 6131 for the 2021 underwriting year. For both our Workers' Compensation Insurance and Segregated Portfolio Cell Reinsurance segments, the decrease in net premiums earned reflected the competitive workers' compensation market conditions and, for our Workers' Compensation Insurance segment, the impact of audit premium returned to policyholders. Net premiums earned in our Specialty P&C segment, excluding NORCAL, increased in 2021 due to the beneficial impacts of our re-underwriting efforts and focus on rate adequacy, partially offset by the prior year effect of a tail policy associated with a large national healthcare account which resulted in $14.3 million of one-time premium written and fully earned during the second quarter of 2020.

The following table shows our consolidated net investment result:

Year Ended December 31
($ in thousands)20212020Change
Net investment income$70,522$71,998$(1,476)(2.1%)
Equity in earnings (loss) of unconsolidated subsidiaries*48,974(11,921)60,895510.8%
Net investment result$119,496$60,077$59,41998.9%
*Equity in earnings (loss) of unconsolidated subsidiaries includes our share of the operating results of interests we hold in certain LPs/LLCs as well as operating losses associated with our tax credit partnership investments, which are designed to generate returns in the form of tax credits and tax-deductible project operating losses.

Our consolidated net investment result for the year ended December 31, 2021 included additional net investment income of $13.1 million from NORCAL. Excluding NORCAL, consolidated net investment income decreased $14.6 million for the year ended December 31, 2021 as compared to 2020 driven by lower yields on our corporate debt securities and short-term investments given the continued low interest rate environment and, to a lesser extent, lower income from our equity portfolio due to a decrease in our allocation to this asset category during the first half of 2021. Furthermore, the decline in net investment income during 2021 reflected the impact of capital planning in anticipation of closing the NORCAL acquisition. The increase in our investment results from our portfolio of investments in LPs/LLCs for 2021 as compared to 2020 was due to higher earnings from several of our LPs/LLCs and the prior year effect of the volatility in the global financial markets related to COVID-19. Our consolidated net investment result for 2021 also included additional earnings from our acquired interests in four LPs from NORCAL of approximately $1.4 million; given the results of our investments in LPs/LLCs are often reported to us on a one quarter lag, the earnings from these investments were not reflected in our results until the third quarter of 2021.

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Expenses

The following table shows our consolidated and segment net loss ratios and net prior accident year reserve development.

Year Ended December 31
($ in millions)20212020Change
Current accident year net loss ratio
Consolidated ratio82.1%89.8%(7.7pts)
Specialty P&C87.5%104.2%(16.7pts)
Workers' Compensation Insurance74.0%69.0%5.0pts
Segregated Portfolio Cell Reinsurance67.1%69.6%(2.5pts)
Lloyd's Syndicates51.9%64.2%(12.3pts)
Calendar year net loss ratio
Consolidated ratio77.4%83.4%(6.0pts)
Specialty P&C82.8%98.5%(15.7pts)
Workers' Compensation Insurance69.7%64.9%4.8pts
Segregated Portfolio Cell Reinsurance51.1%44.6%6.5pts
Lloyd's Syndicates61.6%65.0%(3.4pts)
Favorable (unfavorable) net loss development, prior accident years
Consolidated$45.5$50.4$(4.9)
Specialty P&C$32.9$27.5$5.4
Workers' Compensation Insurance$7.1$7.0$0.1
Segregated Portfolio Cell Reinsurance$10.2$16.5$(6.3)
Lloyd's Syndicates$(4.7)$(0.6)$(4.1)

The primary drivers of the change in our consolidated current accident year net loss ratio for the year ended December 31, 2021 as compared to 2020 were as follows:

(In percentage points)Increase (Decrease) 2021 versus 2020
Estimated ratio increase (decrease) attributable to:
Large National Healthcare Account(5.9 pts)
COVID-19 IBNR Reserve(1.3 pts)
NORCAL Operations2.7 pts
NORCAL Acquisition - Purchase Accounting Adjustment(0.9 pts)
All other, net(2.3 pts)
Decrease in the consolidated current accident year net loss ratio(7.7 pts)

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Excluding the impact of the items specifically identified in the table above, our consolidated current accident year net loss ratio for the year ended December 31, 2021 decreased 2.3 percentage points driven by our Specialty P&C and Lloyd's Syndicates segments, somewhat offset by a higher ratio in our Workers' Compensation Insurance segment. The improvement in the current accident year net loss ratio in our Specialty P&C segment was driven by decreases to certain loss ratios during the first quarter of 2021 in our Standard Physician and Specialty lines of business as we continue to recognize the beneficial impacts of our re-underwriting efforts and focus on rate adequacy. In addition, we observed a reduction in claims frequency in 2020 in our Specialty P&C segment that continued into 2021, some of which is due to our re-underwriting efforts while some of which we believe is associated with the COVID-19 pandemic including the disruption of the court systems. Given the consistent and prolonged nature of this favorable claims frequency trend, we further reduced certain loss ratios in our Standard Physician line of business during the third and fourth quarters of 2021. For our Lloyd's Syndicates segment, the lower current accident year net loss ratio reflected higher reinsurance recoveries as a proportion of gross losses as compared to the prior year period, partially offset by certain catastrophe related losses. In our Workers' Compensation Insurance segment, the increase in the current accident year loss ratio primarily reflects workers returning to full employment after the lifting of pandemic-related restrictions and the labor shortage. We have experienced an increase in reported claim activity in 2021, including increased severity-related claim activity, which we attribute to workers being out of “work shape” as they returned to employment in 2021 as well as the lack of training, alternative work arrangements and employee fatigue due to the labor shortage.

Initial loss ratios associated with NORCAL policies were higher than the average for the other books of business in our Specialty P&C segment; however, we reduced certain NORCAL loss ratios during the fourth quarter of 2021 due to favorable frequency trends, as previously discussed. The net impact of NORCAL operations resulted in a 2.7 percentage point increase in our consolidated current accident year net loss ratio in 2021. Also as a result of our acquisition of NORCAL, our consolidated current accident year loss ratio during 2021 was impacted by amortization of the negative VOBA associated with NORCAL's assumed unearned premium which is recorded as a reduction to current accident year net losses and accounted for a 0.9 percentage point decrease in our consolidated current period ratio. See Note 2 of the Notes to Consolidated Financial Statements for additional information on the NORCAL acquisition and the related purchase accounting adjustments. During 2020, our consolidated current accident year loss ratio was higher due to the effect of a large national healthcare account, net of the impact of related PDR amortization, which accounted for 5.9 percentage points of the decrease in the current period ratio as compared to the prior year period. In addition, our consolidated current accident year loss ratio for 2020 was impacted by a $10 million IBNR reserve we recorded during the second quarter of 2020 for COVID-19 which accounted for 1.3 percentage points of the decrease in the ratio as compared to the prior year period.

In both 2021 and 2020, our consolidated calendar year net loss ratio was lower than our consolidated current accident year net loss ratio due to the recognition of net favorable prior year reserve development, as shown in the previous table. The net favorable loss development recognized in 2021 primarily reflected a lower than anticipated claims severity trend (i.e., the average size of a claim) in our Specialty P&C segment, primarily related to the 2015 through 2020 accident years. For our Workers' Compensation Insurance and Segregated Portfolio Cell Reinsurance segments, the net favorable development in 2021 reflected overall favorable trends in claim closing patterns. Further, favorable development recognized in 2021 included $7.9 million related to the amortization of the purchase accounting fair value adjustment on NORCAL's assumed net reserve and amortization of the negative VOBA associated with NORCAL's DDR reserve which is recorded as a reduction to prior accident year net losses and loss adjustment expenses. We have not recognized any development related to NORCAL's prior accident year reserves since the date of acquisition in 2021. See Note 2 of the Notes to Consolidated Financial Statements for additional information on the NORCAL acquisition and the related purchase accounting adjustments. We also recognized favorable prior year reserve development of $1 million during the third quarter of 2021 in our Specialty P&C segment associated with our COVID-19 IBNR reserve due to the fact that early first notices have not materialized into claims. We continue to remain cautious in our evaluation of our reserves our Specialty P&C segment due to the uncertainty surrounding the length and severity of the pandemic. See additional discussion on our COVID-19 IBNR reserve in the Critical Accounting Estimates section under the heading "Reserve for Losses and Loss Adjustment Expenses".

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Our consolidated and segment underwriting expense ratios were as follows:

Year Ended December 31
20212020Change
Underwriting Expense Ratio
Consolidated (1)27.6%30.0%(2.4pts)
Specialty P&C18.4%23.0%(4.6pts)
Workers' Compensation Insurance31.8%32.9%(1.1pts)
Segregated Portfolio Cell Reinsurance34.0%31.2%2.8pts
Lloyd's Syndicates37.1%39.0%(1.9pts)
Corporate (2)2.7%3.0%(0.3pts)
(1) Includes transaction-related costs associated with our acquisition of NORCAL that are not included in a segment as we do not consider these costs in assessing the financial performance of any of our operating or reportable segments. See Note 18 of the Notes to Consolidated Financial Statements for a reconciliation of our segment results to our consolidated results.
(2) There are no net premiums earned associated with the Corporate segment. Ratios shown are the contribution of the Corporate segment to the consolidated ratio (Corporate operating expenses divided by consolidated net premiums earned).

The change in our consolidated underwriting expense ratio for the year ended December 31, 2021 as compared to 2020 was primarily attributable to the following:

(In percentage points)Increase (Decrease) 2021 versus 2020
Estimated ratio increase (decrease) attributable to:
Decrease in Net Premiums Earned and DPAC amortization(1)(0.4 pts)
NORCAL Operations(5.3 pts)
Transaction-related Costs2.6 pts
Large National Healthcare Account Tail Premium(2)0.6 pts
All other, net0.1 pts
Decrease in the consolidated underwriting expense ratio(2.4 pts)
(1) Excludes earned premium and DPAC amortization contributed by NORCAL since the date of acquisition as well as $14.3 million of earned premium 2020 associated with a large national healthcare account tail policy. See further discussion in Segment Results - Specialty Property & Casualty section that follows.
(2) See previous discussion under the heading "Revenues"

Our consolidated underwriting expense ratio for 2021 was impacted by our acquisition of NORCAL. The additional expenses of NORCAL of $19.3 million had only a nominal effect on the consolidated underwriting expense ratio as they were more than offset by the favorable effect on the ratio of NORCAL net premiums earned of $214.6 million, as previously discussed. The impact of NORCAL decreased our consolidated underwriting expense ratio for 2021 by 5.3 percentage points. Included in NORCAL's expenses for 2021 was approximately $9.4 million of DPAC amortization associated with NORCAL policies written subsequent to our acquisition; however, this level of DPAC amortization is approximately $13.4 million lower than would be considered normal for the period of time post-acquisition due to the application of GAAP purchase accounting rules whereby the capitalized policy acquisition costs for policies written prior to the acquisition date were written off through purchase accounting rather than being expensed pro rata over the remaining term of the associated policies. Normalizing this amortization would have increased our consolidated expense ratio in 2021 by an estimated 1.4 percentage points. Please see Note 2 of the Notes to Consolidated Financial Statements for additional information on the NORCAL acquisition. For 2021, our consolidated underwriting expense ratio was also impacted by transaction-related costs of $25.0 million associated with our acquisition of NORCAL which accounted for an increase of 2.6 percentage points in our current period ratio. We do not consider transaction-related costs in assessing the financial performance of our segments, and thus these costs are only included in our consolidated operating expenses. Please see Note 18 of the Notes to Consolidated Financial Statements for a reconciliation of our segment results to our consolidated results. Excluding the impact of NORCAL and the other items specifically identified in the table above, our consolidated underwriting expense ratio remained relatively unchanged in 2021 as compared to 2020.

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For the year ended December 31, 2021, the underwriting expense ratios in our Specialty P&C and Corporate segments also reflected the impact of a reduction to the management fee charged to the operating subsidiaries of our Specialty P&C segment (excluding the acquired operating subsidiaries of NORCAL) by our Corporate segment effective January 1, 2021 (see further discussion in our Segment Results - Specialty Property & Casualty and Segment Results - Corporate sections that follow). This change had no impact to our consolidated underwriting expense ratio.

Gain on Bargain Purchase

As a result of the NORCAL acquisition, we recognized a non-taxable preliminary gain on bargain purchase of $74.4 million during the second quarter of 2021 representing the excess of the fair value of the identifiable assets acquired and liabilities assumed over the purchase consideration. We do not consider this gain in assessing the financial performance of any of our operating or reportable segments and therefore, we have excluded it from the Segment Results sections that follow. See further discussion around the gain on bargain purchase recognized from the NORCAL acquisition in Note 2 of the Notes to Consolidated Financial Statements.

Taxes

Our effective tax rates for the years ended December 31, 2021 and 2020 were as follows:

($ in thousands)Year Ended December 31
20212020Change
Income (loss) before income taxes$146,607$(217,056)$363,663167.5%
Income tax expense (benefit)2,483(41,329)43,812106.0%
Net income (loss)$144,124$(175,727)$319,851182.0%
Effective tax rate1.7%19.0%(17.3 pts)

We recognized income tax expense in 2021 of $2.5 million and an income tax benefit of $41.3 million in 2020. The most significant item impacting our effective tax rate for the year ended December 31, 2021, which caused it to be lower than the statutory federal income tax rate of 21%, was the aforementioned non-taxable $74.4 million gain on bargain purchase related to the NORCAL acquisition. Additionally, our effective tax rates for the years ended December 31, 2021 and 2020 include the benefit recognized from the tax credits transferred to us from our tax credit partnership investments. Our effective tax rate in 2020 was also impacted by the non-deductible portion of the goodwill impairment related to the Specialty P&C reporting unit recognized during the third quarter of 2020. See further discussion of the goodwill impairment in the Critical Accounting Estimates section under the heading "Goodwill / Intangibles" and Note 8 of the Notes to Consolidated Financial Statements and further information on other notable items impacting our effective tax rates for the years ended December 31, 2021 and 2020 in the Segment Results - Corporate section that follows under the heading "Taxes."

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Operating Ratio

Our operating ratio is our combined ratio, less our investment income ratio. This ratio provides the combined effect of underwriting profitability and investment income. Our operating ratio for the years ended December 31, 2021 and 2020 was as follows:

Year Ended December 31
20212020Change
Combined ratio105.0%113.4%(8.4pts)
Less: investment income ratio7.3%9.1%(1.8pts)
Operating ratio97.7%104.3%(6.6pts)
Combined ratio, excluding transaction-related costs*102.4%113.4%(11.0pts)
*Our consolidated combined ratio as reported in 2021 includes $25.0 million of transaction-related costs included in consolidated operating expenses associated with our acquisition of NORCAL. Given these costs do not reflect normal operating expenses we have excluded their impact from our calculation of the consolidated combined ratio in the table above. See previous discussion under the heading "Expenses."

The primary drivers of the change in our operating ratio were as follows:

(In percentage points)Increase (Decrease) 2021 versus 2020
Estimated ratio increase (decrease) attributable to:
NORCAL Underwriting Results1.0 pts
NORCAL Acquisition - Purchase Accounting Adjustments(1.5 pts)
NORCAL Investment Results(1.3 pts)
Transaction-related Costs2.6 pts
Large National Healthcare Account (1)(5.6 pts)
COVID IBNR Reserve (1)(1.4 pts)
Investment Results (2)3.1 pts
All other, net(3.5 pts)
Decrease in the operating ratio(6.6 pts)
(1) See previous discussion under the heading "Revenues" and "Expenses."
(2) Excludes net investment income contributed by NORCAL since the date of acquisition. See previous discussion under the heading "Revenues."

Excluding the impact of the items specifically identified in the table above, our operating ratio for 2021 decreased by 3.5 percentage points as compared to 2020 primarily due to an improvement in the net loss ratio in our Specialty P&C segment, partially offset by a higher net loss ratio in our Workers' Compensation Insurance segment. See previous discussion in this section under the heading "Expenses" and further discussion in our Segment Operating Results sections that follow.

ROE

ROE is calculated as net income (loss) divided by the average of beginning and ending shareholders’ equity. This ratio measures our overall after-tax profitability and shows how efficiently capital is being used. The $74.4 million gain on bargain purchase recognized during the second quarter of 2021 was excluded in our calculation of ROE for 2021 consistent with our treatment of gains on bargain purchases from previous acquisitions. ROE for the years ended December 31, 2021 and 2020 was as follows:

Year Ended December 31
20212020Change
ROE5.3%(12.3%)17.6pts

Our ROE in 2021 was impacted by our acquisition of NORCAL. NORCAL operations since the date of acquisition, excluding purchase accounting adjustments, decreased our ROE in 2021 by 0.6 percentage points largely due to the fact that loss ratios associated with NORCAL policies are higher than the average for the other books of business in our Specialty P&C segment, partially offset by a lower than normal amount of DPAC amortization due to the application of GAAP purchase

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accounting rules (see previous discussion under the heading "Expenses"). Furthermore, the remaining purchase accounting adjustments associated with the acquisition increased our ROE by 1.1 percentage points. See Note 2 of the Notes to Consolidated Financial Statements for additional information on the NORCAL acquisition and the related purchase accounting adjustments. Excluding the NORCAL acquisition, ROE for 2021 increased 17.1 percentage points driven by the prior year effect of a $161.1 million pre-tax goodwill impairment recognized related to the Specialty P&C reporting unit during the third quarter of 2020. Additionally, the increase in our ROE for 2021 as compared to 2020, excluding NORCAL, reflected higher earnings from certain LPs/LLCs, realized gains from the sale of certain available-for-sale fixed maturity securities and other investments as well as improved underwriting results.

Book Value per Share

Book value per share is calculated as total shareholders' equity at the balance sheet date divided by the total number of common shares outstanding. This ratio measures the net worth of the Company to shareholders on a per share basis. Our book value per share at December 31, 2021 as compared to December 31, 2020 is shown in the following table.

Book Value Per Share
Book Value Per Share at December 31, 2020$25.04
Increase (decrease) to book value per share during the year ended December 31, 2021 attributable to:
Dividends declared(0.20)
Net income (loss) (1)2.67
OCI (2)(1.09)
Other0.04
Book Value Per Share at December 31, 2021$26.46

(1) Includes the $74.4 million gain on bargain purchase as a result of our acquisition of NORCAL, which accounted for $1.38 of the increase in book value per share. See further discussion in Note 2 of the Notes to Consolidated Financial Statements.

(2) Primarily the impact of unrealized investment gains (losses) on our available-for-sale fixed maturity investments. See Note 14 of the Notes to Consolidated Financial Statements for additional information.

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Non-GAAP Financial Measures

Non-GAAP operating income (loss) is a financial measure that is widely used to evaluate performance within the insurance sector. In calculating Non-GAAP operating income (loss), we have excluded the effects of the items listed in the following table that do not reflect normal results. We believe Non-GAAP operating income (loss) presents a useful view of the performance of our insurance operations, however it should be considered in conjunction with net income (loss) computed in accordance with GAAP.

The following table is a reconciliation of net income (loss) to Non-GAAP operating income (loss):

Year Ended December 31
(In thousands, except per share data)20212020
Net income (loss)$144,124$(175,727)
Items excluded in the calculation of Non-GAAP operating income (loss):
Net investment (gains) losses(24,310)(15,678)
Net investment gains (losses) attributable to SPCs which no profit/loss is retained (1)3,2532,436
Transaction-related costs (2)24,977
Goodwill impairment161,115
Guaranty fund assessments (recoupments)22897
Gain on bargain purchase (3)(74,408)
Pre-tax effect of exclusions(70,260)147,970
Tax effect, at 21% (4)2,02816
After-tax effect of exclusions(68,232)147,986
Non-GAAP operating income (loss)$75,892$(27,741)
Per diluted common share:
Net income (loss)$2.67$(3.26)
Effect of exclusions(1.27)2.74
Non-GAAP operating income (loss) per diluted common share$1.40$(0.52)

(1) Net investment gains (losses) on investments related to SPCs are recognized in our Segregated Portfolio Cell Reinsurance segment. SPC results, including any net investment gain or loss, that are attributable to external cell participants are reflected in the SPC dividend expense (income). To be consistent with our exclusion of net investment gains (losses) recognized in earnings, we are excluding the portion of net investment gains (losses) that is included in the SPC dividend expense (income) which is attributable to the external cell participants.

(2) Transaction-related costs associated with our acquisition of NORCAL. We are excluding these costs as they do not reflect normal operating results and are unique and non-recurring in nature.

(3) Gain on bargain purchase associated with our acquisition of NORCAL which is considered unusual, infrequent and non-recurring in nature. As such, we have excluded the gain on bargain purchase from Non-GAAP operating income (loss) as it does not reflect normal operating results.

(4) The 21% rate is the statutory tax rate associated with the taxable or tax deductible items listed above. The taxes associated with the net investment gains (losses) related to SPCs in our Segregated Portfolio Cell Reinsurance segment are paid by the individual SPCs and are not included in our consolidated tax provision or net income (loss); therefore, both the net investment gains (losses) from our Segregated Portfolio Cell Reinsurance segment and the adjustment to exclude the portion of net investment gains (losses) included in the SPC dividend expense (income) in the table above are not tax effected. The 2021 gain on bargain purchase is non-taxable and therefore had no associated income tax impact. The portion of 2020 goodwill impairment loss that is tax deductible was tax effected at the statutory tax rate (21%). The remaining portion of the 2020 goodwill impairment loss is not tax deductible and therefore had no associated income tax benefit.

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Segment Results - Specialty Property & Casualty

Our Specialty P&C segment focuses on professional liability insurance and medical technology liability insurance as discussed in Note 19 of the Notes to Consolidated Financial Statements. On May 5, 2021, we completed our acquisition of NORCAL, an underwriter of healthcare professional liability insurance (Note 2 of the Notes to Consolidated Financial Statements provides additional information regarding this acquisition). Segment results reflected pre-tax underwriting profit or loss from these insurance lines, including the pre-tax underwriting results of NORCAL since the date of acquisition as well as certain purchase accounting adjustments. Segment results for the year ended December 31, 2021 exclude transaction-related costs and a $74.4 million gain on bargain purchase related to the NORCAL acquisition as we do not consider these items in assessing the financial performance of the segment. Segment results included the following:

Year Ended December 31
($ in thousands)20212020Change
Net premiums written$626,147$451,019$175,12838.8%
Net premiums earned$695,008$477,365$217,64345.6%
Other income3,3703,908(538)(13.8%)
Net losses and loss adjustment expenses(575,164)(470,074)(105,090)22.4%
Underwriting, policy acquisition and operating expenses(127,709)(109,599)(18,110)16.5%
Segment results$(4,495)$(98,400)$93,90595.4%
Net loss ratio82.8%98.5%(15.7pts)
Underwriting expense ratio18.4%23.0%(4.6pts)

Premiums Written

Changes in our premium volume within our Specialty P&C segment are generally driven by four primary factors: (1) the amount of new business written, (2) our retention of existing business, (3) the premium charged for business that is renewed, which is affected by rates charged and by the amount and type of coverage an insured chooses to purchase and (4) the timing of premium written through multi-period policies. In addition, premium volume may periodically be affected by shifts in the timing of renewals between periods. For the year ended December 31, 2021, our premium volume was primarily affected by our acquisition of NORCAL (see Note 2 of the Notes to Consolidated Financial Statements).

The professional liability market, which accounts for a majority of the revenues in this segment, remains challenging as physicians continue joining hospitals or larger group practices and are thus no longer purchasing individual or group policies in the standard market. In addition, some competitors have chosen to compete primarily on price; both factors may impact our ability to write new business and retain existing business. Furthermore, the insurance and reinsurance markets have historically been cyclical, characterized by extended periods of intense price competition and other periods of reduced competition. The professional liability area has been particularly affected by these cycles. Underwriting cycles are generally driven by an excess of capacity available and actively pursuing business that is deemed profitable. Changes in the frequency and severity of losses may affect the cycles of the insurance and reinsurance markets significantly. During “soft markets” where price competition is high and underwriting profits are poor, growth and retention of business become challenging which may result in reduced premium volumes.

Gross, ceded and net premiums written were as follows:

Year Ended December 31
($ in thousands)20212020Change
Gross premiums written$681,509$522,911$158,59830.3%
Less: Ceded premiums written55,36271,892(16,530)(23.0%)
Net premiums written$626,147$451,019$175,12838.8%

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Gross Premiums Written

Gross premiums written by component were as follows:

Year Ended December 31
($ in thousands)20212020Change
Professional Liability
HCPL
Standard Physician(1)(14)
Twelve month term$209,938$208,993$9450.5%
Twenty-four month term8,314(8,314)nm
NORCAL Standard Physician(2)111,673111,673nm
Total Standard Physician321,611217,307104,30448.0%
Specialty
Custom Physician(3)(14)46,21064,367(18,157)(28.2%)
NORCAL Custom Physician(4)16,39416,394nm
Hospitals and Facilities(5)(14)51,31049,2442,0664.2%
NORCAL Hospitals and Facilities(6)9,9559,955nm
Senior Care(7)(14)6,7086,3004086.5%
Reinsurance assumed(8)37,75514,46723,288161.0%
Total Specialty168,332134,37833,95425.3%
Total HCPL489,943351,685138,25839.3%
Small Business Unit(9)103,083100,0613,0223.0%
Tail Coverages(10)(14)30,63734,767(4,130)(11.9%)
NORCAL Tail Coverages(11)16,09216,092nm
Total Professional Liability639,755486,513153,24231.5%
Medical Technology Liability(12)40,99735,5635,43415.3%
Other(13)757835(78)(9.3%)
Total$681,509$522,911$158,59830.3%

(1) Standard Physician premium was our greatest source of premium revenues in both 2021 and 2020 and is predominantly comprised of twelve month term policies. The increase in twelve month term policies in 2021 as compared to 2020 was driven by an increase in renewal pricing, the conversion of twenty-four month term policies and, to a lesser extent, new business written, partially offset by retention losses. In addition, twelve month term policies in 2020 included the impact of premium credits granted as a result of the COVID-19 pandemic. Renewal pricing increases during 2021 reflect the rising loss cost environment and new business written reflects general market conditions. Retention losses in 2021 were largely attributable to the loss of two large policies totaling $5.9 million during the third quarter of 2021 due to the insureds' decision to enter into captive arrangements and the loss of two large policies totaling $1.4 million during the first quarter of 2021 due to price competition. Retention losses in 2021 also reflected our targeted state strategy to reassess our underwriting appetite in certain unprofitable states. We will continue to perform a detailed evaluation of venues, specialties and other areas to improve our underwriting results. We also continue to focus on underwriting discipline as we emphasize careful risk selection, rate adequacy, improved contract terms and a willingness to walk away from business that does not fit our goal of achieving a long-term underwriting profit. While retention for 2021 has recovered somewhat from the impact of our re-underwriting efforts over the past two years, it remains lower than our historical average for this line of business as we continue to reevaluate certain states and set our rates to reflect our observations of higher severity trends. Standard Physician premium in 2020 also included twenty-four month term policies that were offered to physician insureds in one selected jurisdiction. We ceased offering twenty-four month term policies beginning in the second quarter of 2020, and the majority of the policies that were up for renewal in 2021 were renewed to twelve month term policies; however, a portion of the premium from 2020 related to policies that will be subject to renewal and conversion in 2022.

(2) NORCAL Standard Physician premium represents premium contributed by NORCAL since the date of acquisition and is comprised of three and twelve month term policies. NORCAL Standard Physician premium in 2021 was

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impacted by an increase in renewal pricing and, to a lesser extent, new business written, partially offset by retention losses, including the loss of one large policy during the second quarter of 2021.

(3) Custom Physician premium includes large complex physician groups, multi-state physician groups and non-standard physicians and is written primarily on an excess and surplus lines basis. The decrease in Custom Physician premium in 2021 was driven by retention losses, including the loss of a $10.4 million policy due to price competition and the non-renewal of two large policies totaling $7.3 million due to our focus on underwriting discipline. The decrease in Custom Physician premium in 2021 also reflected the impact of the dissolution of our arrangement with CAPAssurance as a result of our acquisition of NORCAL, which also resulted in the loss of a large program and two large policies in California totaling $10.2 million during the first quarter of 2021. Partially offsetting the decrease in Custom Physician premium in 2021 was new business written, including the addition of four large policies totaling $5.6 million, and, to a lesser extent, an increase in renewal pricing. Renewal pricing increases for 2021 reflect the rising loss cost environment and new business written reflects general market conditions. The retention rate in our Custom Physician book in 2021 was lower than 2020 which also reflects the impact of the aforementioned dissolution of our arrangement with CAPAssurance as well as the loss of the $10.4 million policy due to price competition, which resulted in a decrease to our Specialty retention rate of 13.6 percentage points. While retention for 2021 has recovered somewhat from the impact of our re-underwriting efforts over the past two years, it remains lower than our historical average for this line of business as our rates are set to reflect our observations of higher severity trends.

(4) NORCAL Custom Physician premium represents premium contributed by NORCAL since the date of acquisition and includes large complex physician groups, multi-state physician groups and non-standard physicians and is written primarily on an excess and surplus lines basis. NORCAL Custom Physician premium in 2021 was impacted by retention losses, including the loss of a $9.0 million policy during the fourth quarter of 2021 due to price competition, partially offset by an increase in renewal pricing and, to a lesser extent, new business written.

(5) Hospitals and Facilities premium (which includes hospitals, surgery centers and miscellaneous medical facilities) increased in 2021 as compared to 2020 driven by new business written, primarily miscellaneous medical facilities, and, to a lesser extent, an increase in renewal pricing, partially offset by retention losses. Renewal pricing increases in 2021 reflect rate increases and contract modifications that we believe are appropriate given the current loss environment and new business written reflects general market conditions. Retention losses in 2021 were driven by the loss of a $2.3 million policy due to price competition, the loss of a $2.0 million policy due to an insured's decision to enter into a captive arrangement, and our decision not to renew certain products. As we substantially completed our re-underwriting efforts on this book of business as of the end of the third quarter of 2020, retention rates have started to normalize.

(6) NORCAL Hospitals and Facilities premium represents premium contributed by NORCAL since the date of acquisition and includes hospitals, surgery centers and miscellaneous medical facilities. NORCAL Hospitals and Facilities premium in 2021 was impacted by retention losses, partially offset by new business written and, to a lesser extent, an increase in renewal pricing.

(7) Senior Care premium includes facilities specializing in long term residential care primarily for the elderly ranging from independent living through skilled nursing. Our Senior Care premium remained relatively unchanged in 2021 as compared to 2020 as retention losses were offset by new business written and renewal pricing increases. The increase in renewal pricing in 2021 was primarily the result of an increase in the rate charged for certain renewed policies in select states. Retention losses in 2021 were driven by our decision not to renew certain classes of Senior Care business based on our expectations of poor loss performance. As we completed our re-underwriting efforts on this book of business during the third quarter of 2020, retention rates have started to normalize.

(8) We offer custom alternative risk solutions including assumed reinsurance. The increase in premium in 2021 primarily reflected an increase premiums assumed on a quota share basis through a strategic partnership since 2016 with an international medical professional liability insurer. For 2021, we increased our participation in the original program and entered into another program with this insurer in a new international territory. We anticipate the volume of premium assumed through this partnership will continue to grow going forward. Our custom alternative risk solutions in 2021 also include an assumed reinsurance arrangement with a regional hospital group entered into during the first quarter of 2021, which resulted in $4.5 million of premium written, comprised of $2.3 million of retroactive premium written and fully earned and $2.2 million of prospective premium written. Furthermore, the increase in premium in 2021 reflected the annual renewal of this arrangement during the third quarter of 2021. See Note 5 of the Notes to Consolidated Financial Statements for further information on this transaction.

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(9) Our Small Business Unit is primarily comprised of premium associated with podiatrists, legal professionals, dentists and chiropractors. Our Small Business Unit premium increased in 2021 as compared to 2020 driven by an increase in renewal pricing and, to a lesser extent, new business written, partially offset by retention losses. The increase in renewal pricing in 2021 was primarily the result of an increase in the rate charged for certain renewed policies in select states.

(10) We offer extended reporting endorsement or "tail" coverage to insureds who discontinue their claims-made coverage with us, and we also periodically offer tail coverage through stand-alone policies. Tail coverage premiums are generally 100% earned in the period written because the policies insure only incidents that occurred in prior periods and are not cancellable. The amount of tail coverage premium written can vary significantly from period to period. The decrease in 2021 as compared to 2020 was primarily due to the prior year effect of a large national healthcare account that exercised its contractual option to purchase tail coverage which resulted in $14.3 million of one-time premiums written and fully earned in the second quarter of 2020. This impact was largely offset by $7.8 million of tail premium written and fully earned during the second quarter of 2021 associated with a Custom Physician policy and two large tail policies totaling $2.1 million written and fully earned during the first quarter of 2021.

(11) NORCAL Tail Coverages represent premium contributed by NORCAL since the date of acquisition and include endorsement coverages to insureds who discontinue their claims-made coverage and may also periodically include tail coverage offered through stand-alone policies. As detailed in the previous footnote, tail coverage premiums are generally 100% earned in the period written and the amount of tail coverage premium written can vary significantly from period to period. NORCAL Tail Coverages in 2021 included five large tail policies totaling $4.5 million written and fully earned.

(12) Our Medical Technology Liability business is marketed throughout the U.S.; coverage is typically offered on a primary basis, within specified limits, to manufacturers and distributors of medical technology and life sciences products including entities conducting human clinical trials. In addition to the previously listed factors that affect our premium volume, our Medical Technology Liability premium is also impacted by the sales volume of insureds. Our Medical Technology Liability premium increased in 2021 as compared to 2020 due to new business written and, to a lesser extent, an increase in renewal pricing, partially offset by retention losses. Renewal pricing increases in 2021 are primarily due to changes in the sales volume of certain insureds, including changes in exposure. Retention losses in 2021 are primarily attributable to an increase in competition on terms and pricing, as well as merger activity within the industry.

(13) This component of gross premiums written includes all other product lines within our Specialty P&C segment.

(14) Certain components of our gross premiums written include alternative market premiums. We currently cede either all or a portion of the alternative market premium, net of reinsurance, to three SPCs of our wholly owned Cayman Islands reinsurance subsidiaries, Inova Re and Eastern Re, which are reported in our Segregated Portfolio Cell Reinsurance segment (see further discussion in the Ceded Premiums Written section that follows). The portion not ceded to the SPCs is retained within our Specialty P&C segment.

Year Ended December 31
($ in millions)20212020Change
Standard Physician$2.0$1.6$0.425.0%
Custom Physician0.1(0.1)nm
Hospitals and Facilities0.10.2(0.1)(50.0%)
Senior Care5.25.2%
Tail Coverages0.80.8nm
Total$8.1$7.1$1.014.1%

The increase in alternative market gross premiums written in 2021 as compared to 2020 was driven by renewal pricing increases, primarily due to an increase in the rate charged for one program and, to a lesser extent, the impact of tail coverages.

We are committed to a rate structure that will allow us to fulfill our obligations to our insureds, while generating competitive long-term returns for our shareholders. Our pricing continues to be based on expected losses as indicated by our historical loss data and available industry loss data. In recent years, this practice has resulted in gradual rate increases and we anticipate further rate increases due to indications of increasing loss severity. Additionally, the pricing of our business includes the effects of filed rates, surcharges and discounts. Renewal pricing also reflects changes in our exposure base, deductibles,

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self-insurance retention limits and other policy terms and conditions. See Gross Premiums Written section for further explanation of changes in renewal pricing.

The change in renewal pricing for our Specialty P&C segment, including by major component, was as follows:

Year Ended December 31
2021
Specialty P&C segment8%
HCPL
Standard Physician(1)8%
Specialty(1)12%
Total HCPL9%
Small Business Unit6%
Medical Technology Liability5%
(1) Includes policies renewed by NORCAL since the date of acquisition.

New business written by major component on a direct basis was as follows:

Year Ended December 31
(In millions)20212020
HCPL
Standard Physician(1)$4.7$2.9
Specialty(1)28.29.0
Total HCPL32.911.9
Small Business Unit3.94.6
Medical Technology Liability6.56.5
Total$43.3$23.0
(1) Includes premium contributed by NORCAL since the date of acquisition.

For our Specialty P&C segment, we calculate retention as annualized renewed premium divided by all annualized premium subject to renewal. Retention is affected by a number of factors. We may lose insureds to competitors or to alternative insurance mechanisms such as risk retention groups, captive arrangements or self-insurance entities (often when physicians join hospitals or large group practices) or due to pricing or other issues. We may choose not to renew an insured as a result of our underwriting evaluation. Insureds may also terminate coverage because they have left the practice of medicine for various reasons, principally for retirement, death or disability, but also for personal reasons.

Retention for our Specialty P&C segment, including by major component, was as follows:

Year Ended December 31
20212020
Specialty P&C segment80%79%
HCPL
Standard Physician(1)86%82%
Specialty(1)58%65%
Total HCPL77%76%
Small Business Unit91%90%
Medical Technology Liability90%85%
(1) Includes premium contributed by NORCAL since the date of acquisition. We are currently in the process of evaluating the NORCAL book of business and implementing ProAssurance's underwriting strategies, which will likely impact retention in future quarters.

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Ceded Premiums Written

Ceded premiums represent the amounts owed to our reinsurers for their assumption of a portion of our losses. Our HCPL and Medical Technology Liability excess of loss reinsurance arrangements renew annually on October 1. For those excess of loss reinsurance arrangements in effect prior to October 1, 2021, we generally retained the first $2 million in risk insured by us and ceded coverages in excess of this amount. Effective October 1, 2021, our HCPL treaty renewed at a lower gross rate and we generally retain from 0% to 5% of the next $24 million of risk for our HCPL coverages in excess of $2 million. Our HCPL excess of loss reinsurance arrangement that renewed on October 1, 2021 also incorporated NORCAL policies. Prior to October 1, 2021, NORCAL policies were reinsured under separate reinsurance agreements, primarily excess of loss, which have historically renewed annually on January 1. For the NORCAL excess of loss reinsurance arrangement that renewed on January 1, 2021, retention was generally the first $2 million in risk and coverages in excess of this amount are ceded up to $24 million. For our Medical Technology Liability treaty which also renewed effective October 1, 2021, we also retain 2.5% of the next $8 million of risk for coverages in excess of $2 million. There were no significant changes in the cost or structure of our Medical Technology Liability treaty upon the October 2021 renewal.

We pay our reinsurers a ceding premium in exchange for their accepting the risk, and in certain of our excess of loss arrangements, the ultimate amount of which is determined by the loss experience of the business ceded, subject to certain minimum and maximum amounts. Given the length of time that it takes to resolve our claims, many years may elapse before all losses recoverable under a reinsurance arrangement are known. As a part of the process of estimating our loss reserve we also make estimates regarding the amounts recoverable under our reinsurance arrangements. As a result, we may have an adjustment to our estimate of expected losses and associated recoveries for prior year ceded losses under certain loss sensitive reinsurance agreements. Any changes to estimates of premiums ceded related to prior accident years are fully earned in the period the changes in estimates occur.

Ceded premiums written were as follows:

Year Ended December 31
($ in thousands)20212020Change
Excess of loss reinsurance arrangements (1)$30,622$33,070$(2,448)(7.4%)
Other shared risk arrangements (2)16,11228,765(12,653)(44.0%)
Premium ceded to SPCs (3)7,2116,1181,09317.9%
NORCAL premiums ceded under separate reinsurance agreements since acquisition (4)2,2532,253nm
Other ceded premiums written3,1003,227(127)(3.9%)
Adjustment to premiums owed under reinsurance agreements, prior accident years, net (5)(3,936)712(4,648)(652.8%)
Total ceded premiums written$55,362$71,892$(16,530)(23.0%)

(1)We generally reinsure risks under our excess of loss reinsurance arrangements pursuant to which the reinsurers agree to assume all or a portion of all risks that we insure above our individual risk retention levels, up to the maximum individual limits offered. Premium due to reinsurers also fluctuates with the volume of written premium subject to cession under the arrangement. In certain of our excess of loss reinsurance arrangements, the premium due to the reinsurer is determined by the loss experience of that business reinsured, subject to certain minimum and maximum amounts. The decrease in ceded premiums written under our excess of loss reinsurance arrangements in 2021 as compared to 2020 primarily reflected the reduced rate on the treaty year effective October 1, 2020 and, to a lesser extent, a decrease in the overall volume of gross premiums written subject to cession. The decrease in ceded premiums written under our excess of loss reinsurance arrangements in 2021 was partially offset by additional ceded premiums of $1.9 million as a result of incorporating NORCAL policies into our existing HCPL excess of loss reinsurance arrangements with the October 1, 2021 renewal (see further discussion in footnote 4 below).

(2)We have entered into various shared risk arrangements, including quota share, fronting and captive arrangements, with certain large healthcare systems and other insurance entities. While we cede a large portion of the premium written under these arrangements, they provide us an opportunity to grow net premium through strategic partnerships. These arrangements primarily include our Ascension Health program and, prior to the fourth quarter of 2020, our CAPAssurance program. Our CAPAssurance program was mutually dissolved on October 1, 2020. During the first quarter of 2021, we entered into a new shared risk arrangement with a regional hospital group. The decrease in ceded premiums written under our shared risk arrangements in 2021 as compared to 2020 was primarily due to the aforementioned dissolution of our arrangement with CAPAssurance and, to a lesser extent, a decrease in premium ceded to our Ascension Health Program, somewhat offset by the premium ceded under our new shared risk arrangement, as previously discussed.

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(3)As previously discussed, as a part of our alternative market solutions, all or a portion of certain healthcare premium written is ceded to SPCs in our Segregated Portfolio Cell Reinsurance segment under either excess of loss or quota share reinsurance agreements, depending on the structure of the individual program. See the Segment Results - Segregated Portfolio Cell Reinsurance section for further discussion on the cession to the SPCs from our Specialty P&C segment. The increase in premiums ceded to SPCs in 2021 as compared to 2020 was driven by renewal pricing increases (see discussion in footnote 14 under the heading "Gross Premiums Written").

(4)NORCAL policies written prior to September 30, 2021 were reinsured under separate reinsurance agreements, primarily excess of loss; however, these policies were incorporated into our existing HCPL excess of loss reinsurance arrangements with the October 1, 2021 renewal, as previously discussed. For NORCAL's previous excess of loss agreement, deposit ceded premium, as defined in the contract, was initially estimated and recorded at the inception date of the treaty, generally January 1, as an estimate of ceded premiums written for the full contract year based on information provided by brokers and reinsurers. As a result, the majority of ceded premiums for NORCAL's excess of loss reinsurance arrangement was recorded by NORCAL before the acquisition in their first quarter 2021 results and were expensed pro rata throughout the contract year. However, these initial estimates of ceded premiums may be periodically adjusted as new information is received and are fully earned in the period the changes in estimates occur. NORCAL's ceded premiums written since acquisition in 2021 under these reinsurance arrangements related almost entirely to an increase in the estimate of premiums owed in excess of the deposit ceded premium initially recorded by NORCAL prior to acquisition and, to a lesser extent, premium related to cyber liability coverages. Effective October 1, 2021, we incorporated NORCAL policies into our existing HCPL excess of loss reinsurance arrangement, as previously discussed.

(5)Given the length of time that it takes to resolve our claims, many years may elapse before all losses recoverable under a reinsurance arrangement are known. As a part of the process of estimating our loss reserve we also make estimates regarding the amounts recoverable under our reinsurance arrangements. As previously discussed, the premiums ultimately ceded under certain of our excess of loss reinsurance arrangements are subject to the losses ceded under the arrangements. As part of the review of our reserves for 2021, we decreased our estimate of expected losses and associated recoveries for prior year ceded losses, as well as our estimate of ceded premiums owed to reinsurers. In 2020, we increased our estimate of expected losses and associated recoveries for prior year ceded losses, as well as our estimate of ceded premiums owed to reinsurers due to reaching the maximum level of premium due under certain prior year excess of loss arrangements. Changes to estimates of premiums ceded related to prior accident years are fully earned in the period the changes in estimates occur.

Ceded Premiums Ratio

As shown in the table below, our ceded premiums ratio was affected in both 2021 and 2020 by revisions to our estimate of premiums owed to reinsurers related to coverages provided in prior accident years.

Year Ended December 31
20212020Change
Ceded premiums ratio, as reported8.1%13.7%(5.6pts)
Less the effect of adjustments in premiums owed under reinsurance agreements, prior accident years (as previously discussed)(0.6%)0.1%(0.7pts)
Ratio, current accident year8.7%13.6%(4.9pts)

The above table reflects ceded premiums written, excluding the effect of prior year ceded premium adjustments, as a percent of gross premiums written. Our current accident year ceded premiums ratio for 2021 was impacted by the inclusion of NORCAL ceded and written premiums since the date of acquisition, which accounted for 1.7 percentage points of the decrease in the ratio as the majority of ceded premiums for NORCAL's excess of loss reinsurance arrangements were recorded before the acquisition, as previously discussed. Excluding the impact of the NORCAL acquisition, our current accident year ceded premium ratio for 2021 decreased 3.2 percentage points as compared to 2020. This decrease was driven by a decrease in premiums ceded under our shared risk arrangements, partially offset by the effect of a large national healthcare account tail policy premium written during the second quarter of 2020. See further discussion on NORCAL ceded premiums and our shared risk arrangements above under the heading "Ceded Premiums Written."

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Net Premiums Earned

Net premiums earned consist of gross premiums earned less the portion of earned premiums that we cede to our reinsurers for their assumption of a portion of our losses. Because premiums are generally earned pro rata over the entire policy period, fluctuations in premiums earned tend to lag those of premiums written. The majority of our policies carry a term of one year; however, some of our Medical Technology Liability policies have a multi-year term and some of our NORCAL Standard Physician policies have a three-month term. In addition, prior to the third quarter of 2020, we wrote certain Standard Physician policies with a twenty-four month term. Tail coverage premiums are generally 100% earned in the period written because the policies insure only incidents that occurred in prior periods and are not cancellable. Retroactive coverage premiums are 100% earned at the inception of the contract, as all of the associated underlying loss events occurred in the past. Additionally, any ceded premium changes due to changes to estimates of premiums owed under reinsurance agreements for prior accident years are fully earned in the period of change.

Net premiums earned were as follows:

Year Ended December 31
($ in thousands)20212020Change
Gross premiums earned$761,411$551,822$209,58938.0%
Less: Ceded premiums earned66,40374,457(8,054)(10.8%)
Net premiums earned$695,008$477,365$217,64345.6%

Gross premiums earned in 2021 included additional earned premiums of approximately $226.0 million from our acquisition of NORCAL. Of that amount of earned premium, approximately $155.1 million was associated with NORCAL policies written prior to our acquisition. Excluding premiums associated with the NORCAL acquisition, gross premiums earned decreased $16.4 million in 2021 as compared to 2020 driven by the pro rata effect of a decrease in the volume of written premium during the preceding twelve months, predominantly in our Specialty line of business, due to our re-underwriting efforts and, to a lesser extent, the dissolution of our arrangement with CAPAssurance. The decrease in gross premiums earned in 2021 also reflected premium adjustments related to loss sensitive policies which decreased earned premium by $2.1 million and increased earned premium by $2.9 million in 2020. In addition, the decrease in gross premiums earned during 2021 reflected the prior year effect of a large national healthcare account that exercised its contractual option to purchase tail coverage which resulted in $14.3 million of one-time premiums written and fully earned during the second quarter of 2020 (see previous discussion in footnote 10 under the heading "Gross Premiums Written"). The decrease in gross premiums earned in 2021 was partially offset by tail premium associated with a Custom Physician policy, which resulted in $7.8 million of one-time written and fully earned during the second quarter of 2021 (see previous discussion in footnote 10 under the heading "Gross Premiums Written") and $2.3 million of retroactive premium written and fully earned associated with an assumed reinsurance program (see previous discussion in footnote 8 under the heading "Gross Premiums Written").

Ceded premiums earned during 2021 included additional ceded premium of approximately $11.4 million from our acquisition of NORCAL, which is primarily attributable to subsequent adjustments made to initial deposit ceded premium recorded under NORCAL's excess of loss reinsurance arrangement (see previous discussion in footnote 4 under the heading "Ceded Premiums Written"). Excluding ceded premiums from our NORCAL acquisition, ceded premiums earned decreased $19.5 million in 2021 as compared to 2020 driven by the pro rata effect of a decrease in premium ceded under our shared risk and excess of loss arrangements during the preceding twelve months and, to a lesser extent, the effect of the decrease in our estimate of ceded premiums owed to reinsurers for expected recoveries on prior year ceded losses in 2021 as compared to an increase in our estimate in 2020.

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Losses and Loss Adjustment Expenses

The determination of calendar year losses involves the actuarial evaluation of incurred losses for the current accident year and the actuarial re-evaluation of incurred losses for prior accident years, including an evaluation of the reserve amounts required for ECO/XPL losses.

Accident year refers to the accounting period in which the insured event becomes a liability of the insurer. For claims-made policies, which represent the majority of the premiums written in our Specialty P&C segment, the insured event generally becomes a liability when the event is first reported to us. For occurrence policies, the insured event becomes a liability when the event takes place. For retroactive coverages, the insured event becomes a liability at inception of the underlying contract. We believe that measuring losses on an accident year basis is the best measure of the underlying profitability of the premiums earned in that period, since it associates policy premiums earned with the estimate of the losses incurred related to those policy premiums.

The following table summarizes calendar year net loss ratios for our Specialty P&C segment by separating losses between the current accident year and all prior accident years. Additionally, the table shows our current accident year net loss ratios were affected by revisions to our estimate of premiums owed to reinsurers related to coverages provided in prior accident years. Furthermore, net loss ratios in the following table include the impact of NORCAL since the date of acquisition.

Net Loss Ratios (1)
Year Ended December 31
20212020Change
Calendar year net loss ratio82.8%98.5%(15.7pts)
Less impact of prior accident years on the net loss ratio(4.7%)(5.7%)1.0pts
Current accident year net loss ratio87.5%104.2%(16.7pts)
Less estimated ratio increase (decrease) attributable to:
Ceded premium adjustments, prior accident years (2)(0.5%)0.2%(0.7pts)
Current accident year net loss ratio, excluding the effect of prior year ceded premium (3)88.0%104.0%(16.0pts)

(1)Net losses, as specified, divided by net premiums earned.

(2)During 2021, we decreased our estimates of premiums owed under reinsurance agreements related to prior accident years which increased net premiums earned (the denominator of the current accident net loss year ratio). During 2020, we increased our estimates of premiums owed under reinsurance agreements related to prior accident years which decreased net premiums earned. See the discussion in the Premiums section for our Specialty P&C segment under the heading "Ceded Premiums Written" for additional information.

(3)Our current accident year net loss ratio, excluding the effect of prior year ceded premium adjustments (as shown in the table above), decreased 16.0 percentage points as compared to 2020. The change in our current accident year net loss ratio was primarily attributable to the following:

(In percentage points)Increase (Decrease) 2021 versus 2020
Estimated ratio increase (decrease) attributable to:
Large National Healthcare Account(9.5 pts)
COVID-19 IBNR Reserve(2.2 pts)
Premium adjustments on loss sensitive policies1.0 pts
NORCAL Operations2.0 pts
NORCAL Acquisition - Purchase Accounting Adjustment(1.4 pts)
All other, net(5.9 pts)
Decrease in current accident year net loss ratio, excluding the effect of prior year ceded premium(16.0 pts)

Excluding the impact of the items specifically identified in the table above, our current accident year net loss ratio during 2021 improved 5.9 percentage points driven by decreases to certain loss ratios during the first quarter of 2021 in our Standard Physician and Specialty lines of business as we continue to recognize the beneficial impacts of our re-underwriting efforts and focus on rate adequacy. In addition, we observed a reduction in claims frequency that continued into 2021, some of which is due to our re-underwriting efforts while some of which we believe is

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associated with the COVID-19 pandemic including the disruption of the court systems. Given the consistent and prolonged nature of this favorable claims frequency trend, we further reduced certain loss ratios in our Standard Physician line of business during the third and fourth quarters of 2021.

Initial loss ratios associated with NORCAL policies were higher than the average for our other books of business in this segment; however, we reduced certain NORCAL loss ratios during the fourth quarter of 2021 due to favorable frequency trends, as previously discussed. The net impact of NORCAL operations resulted in a 2.0 percentage point increase in our current accident year net loss ratio in 2021. We are currently in the process of evaluating the NORCAL book of business and implementing ProAssurance's underwriting strategies. Also as a result of our acquisition of NORCAL, our current accident year net loss ratio in 2021 was impacted by amortization of the negative VOBA associated with NORCAL's assumed unearned premium which is recorded as a reduction to current accident year net losses and accounted for a 1.4 percentage point decrease in our current period ratio. See Note 2 of the Notes to Consolidated Financial Statements for additional information on the NORCAL acquisition and the related purchase accounting adjustments. In addition, our current accident year net loss ratio in 2021 was impacted by changes in premium adjustments related to loss sensitive policies which increased the current period ratio as compared to 2020 by 1.0 percentage point (see previous discussion under the heading "Net Premiums Earned"). Our 2020 current accident year net loss ratio was higher due to the effect of a large national healthcare account, net of the impact of related PDR amortization, which accounted for 9.5 percentage points of the decrease in the 2021 ratio as compared to 2020. In addition, our current accident year net loss ratio in 2020 was impacted by a $10 million IBNR reserve we recorded during the second quarter of 2020 for COVID-19 which accounted for 2.2 percentage points of the decrease in the 2021 ratio as compared to 2020.

We re-evaluate our previously established reserve each quarter based upon the most recently completed actuarial analysis supplemented by any new analysis, information or trends that have emerged since the date of that study. We also take into account currently available industry trend information.

We recognized net favorable prior year accident reserve development of $32.9 million for the year ended December 31, 2021 as compared to $27.5 million for the year ended December 31, 2020. Development recognized during 2021 primarily reflected a lower than anticipated loss emergence, principally related to accident years 2015 through 2020. Development recognized in 2020 principally related to accident years 2014 through 2017. Net favorable prior accident year reserve development recognized in 2021 included a $1.0 million reduction in our IBNR reserve for COVID-19 during the third quarter of 2021 due to the fact that early first notices have not materialized into claims. See additional discussion on the COVID-19 IBNR reserve in the Critical Accounting Estimates section under the heading "Reserve for Losses and Loss Adjustment Expenses". In addition, net favorable prior accident year reserve development recognized in 2021 included an increase for potential ECO/XPL claims of $1.0 million in 2021 as compared to a reduction in the same reserve of $4.0 million in 2020. Furthermore, favorable development recognized in 2021 included $7.9 million related to the amortization of the purchase accounting fair value adjustment on NORCAL's assumed net reserve and amortization of the negative VOBA associated with NORCAL's DDR reserve which is recorded as a reduction to prior accident year net losses and loss adjustment expenses. We have not recognized any development related to NORCAL's prior accident year reserves since the date of acquisition.

A detailed discussion of factors influencing our recognition of loss development is included in our Critical Accounting Estimates section under the heading "Reserve for Losses and Loss Adjustment Expenses." Assumptions used in establishing our reserve are regularly reviewed and updated by management as new data becomes available. Any adjustments necessary are reflected in the then current operations. Due to the size of our reserve, even a small percentage adjustment to the assumptions can have a material effect on our results of operations for the period in which the change is made, as was the case in both 2021 and 2020.

Underwriting, Policy Acquisition and Operating Expenses

Our Specialty P&C segment underwriting, policy acquisition and operating expenses, including NORCAL expenses since the date of acquisition, were comprised as follows:

Year Ended December 31
($ in thousands)20212020Change
DPAC amortization$61,662$53,562$8,10015.1%
Management fees3,7816,136(2,355)(38.4%)
Other underwriting and operating expenses62,26649,90112,36524.8%
Total$127,709$109,599$18,11016.5%

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DPAC amortization for 2021 included approximately $9.4 million of DPAC amortization associated with NORCAL policies written subsequent to our acquisition; however, this level of DPAC amortization is approximately $13.4 million lower than would be considered normal for the period of time post-acquisition due to the application of GAAP purchase accounting rules whereby the capitalized policy acquisition costs for policies written prior to the acquisition date were written off through purchase accounting rather than being expensed pro rata over the remaining term of the associated policies (see Note 2 of the Notes to Consolidated Financial Statements for more information). Excluding NORCAL, DPAC amortization decreased for 2021 as compared to 2020 driven by a lower volume of premium written and a decrease in compensation-related expenses driven by a reduction in headcount as a result of the 2020 organizational restructuring. Partially offsetting the decrease in DPAC amortization for 2021 was a decrease in ceding commission income, which is an offset to expense, from certain of our shared risk arrangements.

Management fees are charged pursuant to a management agreement by the Corporate segment to the operating subsidiaries within our Specialty P&C segment, excluding the acquired operating subsidiaries of NORCAL, for services provided based on the extent to which services are provided to the subsidiary and the amount of premium written by the subsidiary. Fluctuations in the amount of premium written by each subsidiary can result in corresponding variations in the management fee charged to each subsidiary during a particular period. Due to organizational structure enhancements in our Specialty P&C segment during 2020, the extent to which services are provided by the Corporate segment to the operating subsidiaries within the segment decreased effective January 1, 2021. Accordingly, we reduced the fee charged to the operating subsidiaries in 2021.

Other underwriting and operating expenses increased in 2021 primarily due to the addition of approximately $10.0 million of expenses contributed by NORCAL since the date of acquisition and an increase in amortization related to new software placed into service during the second quarter of 2020. In addition, the increase in 2021 reflected higher amounts accrued for performance-related incentive plans due to our improved combined ratio and other performance metrics. These increases in expenses during 2021 were partially offset by lower operating expenses in 2021 resulting from the operational and structural changes implemented over the past two years as well as the effect of $3.4 million of one-time expenses incurred during the prior year. One-time expenses in 2020 were mainly comprised of early retirement benefits granted to certain employees during the third quarter of 2020 as well as expenses associated with the restructuring of our HCPL field office organization, largely during the first half of 2020, consisting of employee severance charges and lease exit costs due to a reduction in physical office locations. The remaining variance in other underwriting and operating expenses for 2021 as compared to 2020 was comprised of individually insignificant components.

Underwriting Expense Ratio (the Expense Ratio)

Our expense ratio for the Specialty P&C segment was as follows:

Year Ended December 31
20212020Change
Underwriting expense ratio18.4%23.0%(4.6pts)

The change in our expense ratio in 2021 as compared to 2020 was primarily attributable to the following:

(In percentage points)Increase (Decrease) 2021 versus 2020
Estimated ratio increase (decrease) attributable to:
Change in Net Premiums Earned and DPAC amortization(1)(0.9 pts)
NORCAL Operations(4.2 pts)
One-time Expenses(0.8 pts)
Large National Healthcare Account Tail Premium(2)0.7 pts
All other, net0.6 pts
Decrease in the underwriting expense ratio(4.6 pts)
(1) Excludes premium and DPAC amortization contributed by NORCAL since the date of acquisition (see Note 2 of the Notes to Consolidated Financial Statements for additional information) as well as $14.3 million of premium in 2020 associated with a large national healthcare account tail policy. In addition, excludes certain one-time expenses included in DPAC amortization in 2020 of $0.6 million.
(2) See previous discussion under the heading "Gross Premiums Written."

Our underwriting expense ratio for 2021 was impacted by our acquisition of NORCAL. The additional expenses of NORCAL of $19.3 million for 2021 had only a nominal effect on the underwriting expense ratio as it was more than offset by the favorable effect on the ratio of net premiums earned of $214.6 million contributed by NORCAL which decreased our

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Specialty P&C segment expense ratio for 2021 by 4.2 percentage points. However, as previously discussed, DPAC amortization associated with NORCAL recorded during 2021 was lower than would be considered normal due to the application of GAAP purchase accounting rules. Normalizing this amortization would have increased our expense ratio for 2021 by an estimated 1.9 percentage points. Excluding the impact of NORCAL and the remaining items identified in the table above, our expense ratio for 2021 increased by 0.6 percentage points primarily due to the impact of an increase in amortization related to new software placed into service during the second quarter of 2020 and higher amounts accrued for performance-related incentive plans. These increases in 2021 as compared to 2020 were partially offset by decreased operating expenses resulting from the operational and structural changes implemented over the past two years, as well as the aforementioned reduction to the management fee charged by the Corporate segment.

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Segment Results - Workers' Compensation Insurance

Our Workers' Compensation Insurance segment includes workers' compensation products provided to employers generally with 1,000 or fewer employees, as discussed in Note 19 of the Notes to Consolidated Financial Statements. Workers' compensation products offered include guaranteed cost policies, policyholder dividend policies, retrospectively-rated policies, deductible policies and alternative market programs. Alternative market programs include program design, fronting, claims administration, risk management, SPC rental, asset management and SPC management services. Alternative market program premiums are 100% ceded to either the SPCs within our Segregated Portfolio Cell Reinsurance segment or, to a limited extent, an unaffiliated captive insurer for one program. Our Workers' Compensation Insurance segment results reflect pre-tax underwriting profit or loss from these workers' compensation products, exclusive of investment results, which are included in our Corporate segment. Segment results included the following:

Year Ended December 31
($ in thousands)20212020Change
Net premiums written$161,865$164,871$(3,006)(1.8%)
Net premiums earned$164,600$171,772$(7,172)(4.2%)
Other income2,2112,216(5)(0.2%)
Net losses and loss adjustment expenses(114,704)(111,552)(3,152)2.8%
Underwriting, policy acquisition and operating expenses(52,418)(56,449)4,031(7.1%)
Segment results$(311)$5,987$(6,298)(105.2%)
Net loss ratio69.7%64.9%4.8 pts
Underwriting expense ratio31.8%32.9%(1.1 pts)

Premiums Written

Our workers’ compensation premium volume is driven by five primary factors: (1) the amount of new business written, (2) retention of our existing book of business, (3) premium rates charged on our renewal book of business, (4) changes in payroll exposure and (5) audit premium.

Gross, ceded and net premiums written were as follows:

Year Ended December 31
($ in thousands)20212020Change
Gross premiums written$240,546$246,791$(6,245)(2.5%)
Less: Ceded premiums written78,68181,920(3,239)(4.0%)
Net premiums written$161,865$164,871$(3,006)(1.8%)

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Gross Premiums Written

Gross premiums written by product were as follows:

Year Ended December 31
($ in thousands)20212020Change
Traditional business:
Guaranteed cost$138,756$145,546$(6,790)(4.7%)
Policyholder dividend21,46820,4641,0044.9%
Deductible4,6134,581320.7%
Retrospective(1)2,7419091,832201.5%
Other6,3577,094(737)(10.4%)
Alternative market business(2)67,82169,487(1,666)(2.4%)
Change in EBUB estimate(1,210)(1,290)80(6.2%)
Total$240,546$246,791$(6,245)(2.5%)

(1) The change in retrospectively-rated policies included an adjustment that decreased premium by $1.1 million and $2.5 million during the years ended December 31, 2021 and 2020, respectively.

(2) A majority of alternative market premiums are ceded to SPCs in our Segregated Portfolio Cell Reinsurance segment. See further discussion on alternative market gross premiums written in our Segment Operating Results - Segregated Portfolio Cell Reinsurance section under the heading "Gross Premiums Written" that follows.

Gross premiums written decreased during the year ended December 31, 2021 as compared to 2020, reflecting a decrease in audit premium and new business, partially offset by improvement in both renewal retention and renewal rate changes. Policy audits processed during 2021 resulted in audit premium returned to policyholders totaling $0.8 million as compared to audit premium billed to policyholders of $0.6 million during 2020. We reduced our EBUB estimate by $1.2 million in 2021 as compared to $1.3 million in 2020. The decrease in audit premium processed as well as the reduction of our EBUB estimate in 2021 primarily reflected the impact of COVID-19 on actual and expected final payroll audits for policies written prior to the onset of the pandemic in 2020. Renewal retention was 87% in 2021 as compared to 84% for 2020. The 2020 renewal retention was impacted by the reduction in premium funding for a large alternative market program. Renewal rate decreased 2% in 2021 as compared to 4% in 2020. New business written decreased $6.3 million during 2021 as compared to 2020, reflecting the competitive workers' compensation market conditions and a decrease in new business submissions in 2021, which were 18% lower than 2020.

We retained 23 of the 24 workers' compensation alternative market programs up for renewal during the year ended December 31, 2021. During the fourth quarter of 2021, we placed one program into run-off due to continued unfavorable underwriting results. The program had gross written premium of $1.8 million for the year ended December 31, 2021.

New business, audit premium, renewal retention and renewal price changes for our traditional business and the alternative market business are shown in the table below:

Year Ended December 31
20212020
($ in millions)Traditional BusinessAlternative Market BusinessSegment ResultsTraditional BusinessAlternative Market BusinessSegment Results
New business$17.8$3.3$21.1$23.7$3.7$27.4
Audit premium (excluding EBUB)$(1.9)$1.1$(0.8)$0.7$(0.1)$0.6
Retention rate (1)86%89%87%84%84%84%
Change in renewal pricing (2)(1%)(4%)(2%)(4%)(4%)(4%)
(1) We calculate our workers' compensation retention rate as annualized expiring renewed premium divided by all annualized expiring premium subject to renewal. Our retention rate can be impacted by various factors, including price or other competitive issues, insureds being acquired, or a decision not to renew based on our underwriting evaluation.
(2) The pricing of our business includes an assessment of the underlying policy exposure and market conditions. We continue to base our pricing on expected losses, as indicated by our historical loss data.

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Ceded Premiums Written

Ceded premiums written were as follows:

Year Ended December 31
($ in thousands)20212020Change
Premiums ceded to SPCs$64,639$66,725$(2,086)(3.1%)
Premiums ceded to external reinsurers12,76812,795(27)(0.2%)
Premiums ceded to unaffiliated captive insurer3,1822,76242015.2%
Change in return premium estimate under external reinsurance(605)(39)(566)1,451.3%
Estimated revenue share under external reinsurance(1,303)(323)(980)303.4%
Total ceded premiums written$78,681$81,920$(3,239)(4.0%)

Premiums ceded to SPCs represent alternative market business that is ceded under 100% quota share agreements to the SPCs in our Segregated Portfolio Cell Reinsurance segment. Premiums ceded to unaffiliated captive insurer represent alternative market business for one program that is ceded under a 100% quota share reinsurance agreement. Alternative market premiums written decreased in 2021, which resulted in lower premium ceded to SPCs. See further discussion on alternative market gross premiums written in our Segment Operating Results - Segregated Portfolio Cell Reinsurance section under the heading "Gross Premiums Written" that follows.

Under our external reinsurance agreement for traditional business, we retain the first $0.5 million in risk insured by us and cede losses in excess of this amount on each loss occurrence under our primary external reinsurance treaty, subject to an AAD equal to 3.5% of ceded earned premium for the treaty year effective May 1, 2021. Per our reinsurance agreements, we cede premiums related to our traditional business on an earned premium basis. The decrease in premiums ceded to external reinsurers during the year ended December 31, 2021 primarily reflected lower earned premium, partially offset by an increase in reinsurance rates effective May 1, 2021.

Changes in the return premium estimate reflected adjustments to our estimate of expected future recovery of ceded premium based on the underlying loss experience of our reinsurance contracts that include a provision for return premium. We increased our estimate of return premium by $0.6 million for the year ended December 31, 2021 as compared to a nominal amount in 2020. The change in estimated return premium for the year ended December 31, 2021 primarily reflected favorable prior year loss development on previously reported reinsured claims.

Ceded Premiums Ratio

Ceded premiums ratio was as follows:

Year Ended December 31
20212020Change
Ceded premiums ratio, as reported32.4%32.8%(0.4pts)
Less the effect of:
Premiums ceded to SPCs (100%)24.6%24.6%pts
Retrospective premium adjustments%0.1%(0.1pts)
Premiums ceded to unaffiliated captive insurers (100%)1.7%1.4%0.3pts
Change in EBUB0.1%0.1%pts
Change in return premium estimate under external reinsurance(0.4%)%(0.4pts)
Estimated revenue share(0.7%)(0.2%)(0.5pts)
Assumed premiums earned (not ceded to external reinsurers)(0.2%)(0.3%)0.1pts
Ceded premiums ratio (related to external reinsurance), less the effects of above7.3%7.1%0.2pts

The above table reflects traditional ceded premiums earned as a percent of traditional gross premiums earned. As discussed above, we cede premiums in our traditional business to external reinsurers on an earned premium basis. The increase in the ceded premiums ratio in 2021 as compared to 2020 primarily reflected the increase in reinsurance rates.

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Net Premiums Earned

Net premiums earned consist of gross premiums earned less the portion of earned premiums that we cede to SPCs in our Segregated Portfolio Cell Reinsurance segment, external reinsurers (including changes related to the return premium and revenue share estimates) and the unaffiliated captive insurer. Because premiums are earned pro rata over the entire policy period, fluctuations in premiums earned tend to lag those of premiums written. Our workers’ compensation policies are twelve month term policies, and premiums are earned on a pro rata basis over the policy period. Net premiums earned also include premium adjustments related to the audit of our insureds' payrolls, changes in our EBUB estimate and premium adjustments related to retrospectively-rated policies. Payroll audits are conducted subsequent to the end of the policy period and any related premium adjustments processed are recorded as fully earned in the current period. In addition, we record an estimate for EBUB and evaluate the estimate on a quarterly basis.

Net premiums earned were as follows:

Year Ended December 31
($ in thousands)20212020Change
Gross premiums earned$243,665$255,484$(11,819)(4.6%)
Less: Ceded premiums earned79,06583,712(4,647)(5.6%)
Net premiums earned$164,600$171,772$(7,172)(4.2%)

The decrease in net premiums earned during the year ended December 31, 2021 as compared to 2020 primarily reflected the pro rata effect of a reduction in net premiums written during the preceding twelve months and the impact of audit premium returned to policyholders. The decrease in net premiums earned during the year ended December 31, 2021 was partially offset by a decrease in negative premium adjustments under retrospectively-rated policies and a decrease in ceded earned premium, which reflected the increased revenue share and return premium estimates.

Losses and Loss Adjustment Expenses

We estimate our current accident year loss and loss adjustment expenses by developing actual reported losses using historical loss development factors, adjusted to reflect current and expected trends based on various internal analyses and supplemental information. The following table summarizes calendar year net loss ratios by separating losses between the current accident year and all prior accident years. Calendar year and current accident year net loss ratios by component were as follows:

Year Ended December 31
20212020Change
Calendar year net loss ratio69.7%64.9%4.8pts
Less impact of prior accident years on the net loss ratio(4.3%)(4.1%)(0.2pts)
Current accident year net loss ratio74.0%69.0%5.0pts

The current accident year loss ratio increased in 2021 as compared to 2020, reflecting workers returning to full employment in 2021 after the lifting of pandemic-related restrictions and the labor shortage. We experienced an increase in reported claim activity in 2021, including an increase in severity-related claim activity. The increase in reported claim activity is attributable to workers being out of “work shape” as they returned to employment in 2021 as well as the lack of training, alternative work arrangements and employee fatigue due to the labor shortage. The current accident year loss ratio in 2021 was also impacted by the continuation of intense price competition and the resulting renewal rate decreases as well as the reduction in net premiums earned related to negative audit premium, as previously discussed.

Calendar year incurred losses (excluding IBNR) in excess of our per occurrence reinsurance retention, before consideration of the AAD (see previous discussion under the heading "Ceded Premiums Written"), increased $11.3 million in 2021 as compared to 2020. Current accident year ceded incurred losses totaled $6.9 million in 2021 as compared to $2.8 million in 2020. We retained calendar year incurred losses in excess of our per occurrence retention totaling $6.6 million for the year ended December 31, 2021 which reflected losses within the AAD.

We recognized net favorable prior year development related to our previously established reserve of $7.1 million for the year ended December 31, 2021 as compared to $7.0 million for 2020. The net favorable prior year reserve development for the years ended December 31, 2021 and 2020 reflected overall favorable trends in claim closing patterns. Net favorable development for the year ended December 31, 2021 primarily related to accident years 2012 through 2017. Net favorable development for the year ended December 31, 2020 primarily related to accident years 2014 through 2017.

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Underwriting, Policy Acquisition and Operating Expenses

Underwriting, policy acquisition and operating expenses include the amortization of commissions, premium taxes and underwriting salaries, which are capitalized and deferred over the related workers’ compensation policy period, net of ceding commissions earned. The capitalization of underwriting salaries can vary as they are subject to the success rate of our contract acquisition efforts. These expenses also include a management fee charged by our Corporate segment, which represents intercompany charges pursuant to a management agreement, and the amortization of intangible assets, primarily related to the acquisition of Eastern by ProAssurance. The management fee is based on the extent to which services are provided to the subsidiary and the amount of premium written by the subsidiary.

Our Workers' Compensation Insurance segment underwriting, policy acquisition and operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20212020Change
DPAC amortization$29,092$31,547$(2,455)(7.8%)
Management fees1,8041,861(57)(3.1%)
Other underwriting and operating expenses34,35937,642(3,283)(8.7%)
Policyholder dividend expense1,1551,0511049.9%
SPC ceding commission offset(13,992)(15,652)1,660(10.6%)
Total$52,418$56,449$(4,031)(7.1%)

The decrease in DPAC amortization for the year ended December 31, 2021 as compared to 2020 primarily reflected the decrease in net premiums earned.

The decrease in other underwriting and operating expenses for the year ended December 31, 2021 as compared to 2020 primarily reflected a decrease in compensation-related costs driven by a reduction in headcount as a result of the third quarter of 2020 restructuring and a reduction in our allowance for expected credit losses, partially offset by an increase in expenses related to our policy administration and claim system implementation project. Additionally, the decrease in other underwriting and operating expenses in 2021 as compared to 2020 reflected the prior year effect of one-time costs of $0.9 million primarily comprised of employee severance costs associated with the 2020 restructuring.

As previously discussed, alternative market premiums written by our Workers' Compensation Insurance segment unit are 100% ceded, less a ceding commission, to either the SPCs in our Segregated Portfolio Cell Reinsurance segment or, to a limited extent, an unaffiliated captive insurer. The ceding commission charged to the SPCs consists of an amount for fronting fees, cell rental fees, commissions, premium taxes and risk management fees. The fronting fees, commissions, premium taxes and risk management fees are recorded as an offset to underwriting, policy acquisition and operating expenses. Cell rental fees are recorded as a component of other income and claims administration fees are recorded as ceded ULAE. The decrease in SPC ceding commissions earned for the year ended December 31, 2021 as compared to 2020, primarily reflected the decrease in alternative market ceded earned premium.

Underwriting Expense Ratio (the Expense Ratio)

The underwriting expense ratio included the impact of the following:

Year Ended December 31
20212020Change
Underwriting expense ratio, as reported31.8%32.9%(1.1pts)
Less estimated ratio increase (decrease) attributable to:
Impact of ceding commissions received from SPCs3.3%3.2%0.1pts
Retrospective premium adjustment0.1%0.3%(0.2pts)
Impact of audit premium0.4%0.1%0.3pts
Change in return premium estimate under external reinsurance(0.1%)%(0.1pts)
Estimated revenue share(0.2%)%(0.2pts)
Underwriting expense ratio, less listed effects28.3%29.3%(1.0pts)

Excluding the items noted in the table above, the expense ratio decreased for the year ended December 31, 2021, primarily reflecting the reduction in compensation-related costs and the allowance for credit losses noted above, partially offset by the decrease in net premiums earned.

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Segment Results - Segregated Portfolio Cell Reinsurance

The Segregated Portfolio Cell Reinsurance segment includes the results (underwriting profit or loss, plus investment results, net of U.S. federal income taxes) of SPCs at Inova Re and Eastern Re, our Cayman Islands SPC operations, as discussed in Note 19 of the Notes to Consolidated Financial Statements. SPCs are segregated pools of assets and liabilities that provide an insurance facility for a defined set of risks. Assets of each SPC are solely for the benefit of that individual cell and each SPC is solely responsible for the liabilities of that individual cell. Assets of one SPC are statutorily protected from the creditors of the others. Each SPC is owned, fully or in part, by an individual company, agency, group or association and the results of the SPCs are attributable to the participants of that cell. We participate to a varying degree in the results of selected SPCs and, for the SPCs in which we participate, our participation interest ranges from a low of 20% to a high of 85%. SPC results attributable to external cell participants are reported as an SPC dividend (expense) income in our Segregated Portfolio Cell Reinsurance segment. In addition, our Segregated Portfolio Cell Reinsurance segment includes the investment results of the SPCs as the investments are solely for the benefit of the cell participants and investment results attributable to external cell participants are reflected in the SPC dividend (expense) income. As of December 31, 2021, there were 27 (4 inactive) SPCs. The SPCs assume workers' compensation insurance, healthcare professional liability insurance or a combination of the two from our Workers' Compensation Insurance and Specialty P&C segments. As of December 31, 2021, there were two SPCs that assumed both workers' compensation insurance and healthcare professional liability insurance and one SPC that assumed only healthcare professional liability insurance.

Segment results reflects our share of the underwriting and investment results of the SPCs in which we participate, and included the following:

Year Ended December 31
($ in thousands)20212020Change
Net premiums written$63,042$64,159$(1,117)(1.7%)
Net premiums earned$63,688$66,352$(2,664)(4.0%)
Net investment income8141,084(270)(24.9%)
Net investment gains (losses)4,0803,08599532.3%
Other income3205(202)(98.5%)
Net losses and loss adjustment expenses(32,569)(29,605)(2,964)10.0%
Underwriting, policy acquisition and operating expenses(21,635)(20,709)(926)4.5%
SPC U.S. federal income tax expense (1)(1,947)(1,746)(201)11.5%
SPC net results12,43418,666(6,232)(33.4%)
SPC dividend (expense) income (2)(10,050)(14,304)4,254(29.7%)
Segment results (3)$2,384$4,362$(1,978)(45.3%)
Net loss ratio51.1%44.6%6.5 pts
Underwriting expense ratio34.0%31.2%2.8 pts
(1) Represents the provision for U.S. federal income taxes for SPCs at Inova Re, which have elected to be taxed as a U.S. corporation under Section 953(d) of the Internal Revenue Code. U.S. federal income taxes are included in the total SPC net results and are paid by the individual SPCs.
(2) Represents the net (profit) loss attributable to external cell participants.
(3) Represents our share of the net profit (loss) of the SPCs in which we participate.

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Premiums Written

Premiums in our Segregated Portfolio Cell Reinsurance segment are assumed from either our Workers' Compensation Insurance or Specialty P&C segments. Premium volume is driven by five primary factors: (1) the amount of new business written, (2) retention of the existing book of business, (3) premium rates charged on the renewal book of business and, for workers' compensation business, (4) changes in payroll exposure and (5) audit premium.

Gross, ceded and net premiums written were as follows:

Year Ended December 31
($ in thousands)20212020Change
Gross premiums written$71,850$72,843$(993)(1.4%)
Less: Ceded premiums written8,8088,6841241.4%
Net premiums written$63,042$64,159$(1,117)(1.7%)

Gross Premiums Written

Gross premiums written reflected reinsurance premiums assumed by component as follows:

Year Ended December 31
($ in thousands)20212020Change
Workers' compensation$64,639$66,725$(2,086)(3.1%)
Healthcare professional liability7,2116,1181,09317.9%
Gross Premiums Written$71,850$72,843$(993)(1.4%)

Gross premiums written for the years ended December 31, 2021 and 2020 were primarily comprised of workers' compensation coverages assumed from our Workers' Compensation Insurance segment. Workers' compensation gross premiums written decreased during the year ended December 31, 2021 as compared to 2020, which primarily reflected the competitive workers’ compensation market conditions and the resulting renewal rate decreases of 4%, partially offset by an improvement in renewal retention. The renewal retention rate during 2020 includes the impact of a reduction in premium funding for a large workers' compensation program. We do not participate in this program; therefore, the reduction in premium funding had no effect on the segment results for the year ended December 31, 2021. The increase in healthcare professional liability gross premiums written in 2021 as compared to 2020 primarily reflected higher renewal pricing and exposure increases in two programs. We retained 22 of the 23 workers' compensation alternative market programs up for renewal for the year ended December 31, 2021. During the fourth quarter, we placed one program into run-off due to continued unfavorable underwriting results. The program had gross written premium of $1.8 million for the year ended December 31, 2021. We retained 100% of the 3 healthcare professional liability programs up for renewal during 2021.

New business, audit premium, retention and renewal price changes for the assumed workers' compensation premium is shown in the table below:

Year Ended December 31
($ in millions)20212020
New business$3.3$3.7
Audit premium (including EBUB)$1.1$(0.1)
Retention rate (1)89%84%
Change in renewal pricing (2)(4%)(4%)
(1) We calculate our workers' compensation retention rate as annualized expiring renewed premium divided by all annualized expiring premium subject to renewal. Our retention rate can be impacted by various factors, including price or other competitive issues, insureds being acquired, or a decision not to renew based on our underwriting evaluation.
(2) The pricing of our business includes an assessment of the underlying policy exposure and market conditions. We continue to base our pricing on expected losses, as indicated by our historical loss data.

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Ceded Premiums Written

Ceded premiums written were as follows:

Year Ended December 31
($ in thousands)20212020Change
Ceded premiums written$8,808$8,684$1241.4%

For the workers' compensation business, each SPC has in place its own external reinsurance arrangements. The healthcare professional liability business is assumed net of reinsurance from our Specialty P&C segment; therefore, there are no ceded premiums related to the healthcare professional liability business reflected in the table above. The risk retention for each loss occurrence for the workers' compensation business ranges from $0.3 million to $0.4 million based on the program, with limits up to $119.7 million. In addition, each program has aggregate reinsurance coverage between $1.1 million and $2.1 million on a program year basis. Per the SPC external reinsurance agreements, premiums are ceded on a written premium basis. The change in ceded premiums written in 2021 as compared to 2020 primarily reflected the impact of rate increases under the external reinsurance contract, partially offset by the decrease in workers' compensation gross premiums written. External reinsurance rates vary based on the alternative market program.

Ceded Premiums Ratio

Ceded premiums ratio was as follows:

Year Ended December 31
20212020Change
Ceded premiums ratio13.6%13.0%0.6pts

The above table reflects ceded premiums as a percent of gross premiums written for the workers' compensation business only; healthcare professional liability business is assumed net of reinsurance, as discussed above. The ceded premiums ratio reflects the weighted average reinsurance rates of all SPC programs. The increase in the ceded premiums ratio for the year ended December 31, 2021 reflects an increase in reinsurance rates.

Net Premiums Earned

Net premiums earned consist of gross premiums earned less the portion of earned premiums that the SPCs cede to external reinsurers. Because premiums are generally earned pro rata over the entire policy period, fluctuations in premiums earned tend to lag those of premiums written. Policies ceded to the SPCs are twelve month term policies and premiums are earned on a pro rata basis over the policy period. Net premiums earned also include premium adjustments related to the audit of workers' compensation insureds' payrolls. Payroll audits are conducted subsequent to the end of the policy period and any related adjustments processed are recorded as fully earned in the current period.

Gross, ceded and net premiums earned were as follows:

Year Ended December 31
($ in thousands)20212020Change
Gross premiums earned$72,359$75,112$(2,753)(3.7%)
Less: Ceded premiums earned8,6718,760(89)(1.0%)
Net premiums earned$63,688$66,352$(2,664)(4.0%)

The decrease in net premiums earned during the year ended December 31, 2021 primarily reflected the pro rata effect of a reduction in net premiums written during the preceding twelve months.

Net Investment Income and Net Investment Gains (Losses)

Net investment income for the years ended December 31, 2021 and 2020 was primarily attributable to interest earned on available-for-sale fixed maturity investments, which primarily include investment-grade corporate debt securities. We recognized $4.1 million and $3.1 million of net investment gains for the years ended December 31, 2021 and 2020, respectively, which primarily reflected an increase in the fair value of our equity portfolio.

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Losses and Loss Adjustment Expenses

The following table summarizes the calendar year net loss ratios by separating losses between the current accident year and all prior accident years. The current accident year net loss ratio reflects the aggregate loss ratio for all programs. Loss reserves are estimated for each program on a quarterly basis. Due to the size of some of the programs, quarterly loss results can create volatility in the current accident year net loss ratio from period to period.

Calendar year and current accident year net loss ratios for the years ended December 31, 2021 and 2020 were as follows:

Year Ended December 31
20212020Change
Calendar year net loss ratio51.1%44.6%6.5pts
Less impact of prior accident years on the net loss ratio(16.0%)(25.0%)9.0pts
Current accident year net loss ratio67.1%69.6%(2.5pts)

The current accident year net loss ratio decreased in 2021 as compared to 2020, primarily reflecting favorable trends in the prior accident year claim results and their impact on our analysis of the current accident year loss estimate. The decrease was partially offset by the continuation of intense price competition and the resulting renewal rate decreases in the workers' compensation business as well as the impact of higher claim activity related to workers returning to full employment in 2021 after the lifting of pandemic-related restrictions and the labor shortage.

Calendar year incurred losses (excluding IBNR) ceded to our external reinsurers increased $5.2 million for the year ended December 31, 2021 as compared to 2020. Current accident year ceded incurred losses (excluding IBNR) increased $2.3 million for the year ended December 31, 2021 as compared to 2020.

We recognized net favorable prior year reserve development of $10.2 million and $16.5 million for the years ended December 31, 2021 and 2020, respectively.

Net favorable prior year reserve development in the workers' compensation business totaled $7.6 million in 2021 as compared to $12.1 million in 2020. The 2021 net favorable prior year reserve development related primarily to accident year 2015 and accident years 2018 through 2020. The 2020 net favorable development related primarily to accident years 2018 and 2019.

Net favorable prior year reserve development in the healthcare professional liability business totaled $2.5 million in 2021 as compared to $4.4 million in 2020. The 2021 net favorable prior year reserve development related primarily to accident years 2018 through 2020, while the 2020 net favorable prior year reserve development related primarily to accident years 2017 through 2019.

Underwriting, Policy Acquisition and Operating Expenses

Our Segregated Portfolio Cell Reinsurance segment underwriting, policy acquisition and operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20212020Change
DPAC amortization$18,730$19,636$(906)(4.6%)
Policyholder dividend expense50872436605.6%
Other underwriting and operating expenses2,3971,0011,396139.5%
Total$21,635$20,709$9264.5%

DPAC amortization primarily represents ceding commissions, which vary by program and are paid to our Workers' Compensation Insurance and Specialty P&C segments for premiums assumed. Ceding commissions include an amount for fronting fees, commissions, premium taxes and risk management fees, which are reported as an offset to underwriting, policy acquisition and operating expenses within our Workers' Compensation Insurance and Specialty P&C segments. In addition, ceding commissions paid to our Workers' Compensation Insurance segment include cell rental fees which are recorded as other income and claims administration fees which are recorded as ceded ULAE within our Workers' Compensation Insurance segment.

Other underwriting and operating expenses primarily include bank fees, professional fees and changes in the allowance for expected credit losses. The increase in other underwriting and operating expenses for the year ended December 31, 2021 as

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compared to 2020 primarily reflected the change in our allowance for expected credit losses related to one program in which we do not participate, partially offset by a decrease in professional fees.

The increase in policyholder dividend expense for the year ended December 31, 2021 as compared to 2020, related primarily to one SPC program, in which we do not participate.

Underwriting Expense Ratio (the Expense Ratio)

The underwriting expense ratio included the impact of the following:

Year Ended December 31
20212020Change
Underwriting expense ratio, as reported34.0%31.2%2.8pts
Less: impact of audit premium on expense ratio(0.5%)0.1%(0.6pts)
Underwriting expense ratio, excluding the effect of audit premium34.5%31.1%3.4pts

Excluding the effect of audit premium, the underwriting expense ratio increased for the year ended December 31, 2021. The increase primarily reflected the change in the allowance for expected credit losses and policyholder dividend expense, as discussed above, as well as the decrease in net premiums earned.

SPC U.S. Federal Income Tax Expense

The SPCs at Inova Re have made a 953(d) election under the U.S. Internal Revenue Code and are subject to U.S. federal income tax. U.S. federal income taxes incurred totaled $1.9 million and $1.7 million for the years ended December 31, 2021 and 2020, respectively. U.S. federal income taxes are included in the total SPC net results and are paid by the individual SPCs.

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Segment Results - Lloyd's Syndicates

Our Lloyd's Syndicates segment includes the results from our participation in certain Syndicates at Lloyd's of London. In addition to our participation in Syndicate results, we have investments in and other obligations to our Lloyd's Syndicates consisting of a Syndicate Credit Agreement and FAL requirements. For the 2021 underwriting year, our FAL was comprised of investment securities and cash and cash equivalents deposited with Lloyd's which at December 31, 2021 had a fair value of approximately $37.8 million, as discussed in Note 4 of the Notes to Consolidated Financial Statements. During the second and fourth quarters of 2021, we received a return of approximately $24.5 million and $8.0 million, respectively, of cash from our FAL balances given the reduction in our participation in the results of Syndicate 1729, to 5% from 29%, and Syndicate 6131, to 50% from 100%, for the 2021 underwriting year. Further, during the fourth quarter of 2021, we received a return of approximately $26.6 million of cash from our FAL balances given Syndicate 6131 ceased underwriting on a quota share basis with Syndicate 1729 as Syndicate 6131's business is retained within Syndicate 1729 beginning with the 2022 underwriting year.

We normally report results from our involvement in Lloyd's Syndicates on a quarter lag, except when information is available that is material to the current period. Furthermore, the investment results associated with our FAL investments and certain U.S. paid administrative expenses are reported concurrently as that information is available on an earlier time frame.

Lloyd's Syndicate 1729. We provide capital to Syndicate 1729, which covers a range of property and casualty insurance and reinsurance lines in both the U.S. and international markets. The remaining capital for Syndicate 1729 is provided by unrelated third parties, including private names and other corporate members. As previously discussed, we decreased our participation in the results of Syndicate 1729 for the 2021 underwriting year to 5% to support and grow our core insurance operations. Due to the quarter lag, this reduced participation was not reflected in our results until the second quarter of 2021. Syndicate 1729 had a maximum underwriting capacity of £185 million (approximately $250 million based on December 31, 2021 exchange rates) for the 2021 underwriting year, of which £9 million (approximately $13 million based on December 31, 2021 exchange rates) was our allocated underwriting capacity. For the 2022 underwriting year, our participation in the results of Syndicate 1729 remains unchanged at 5%. Syndicate 1729's maximum underwriting capacity for the 2022 underwriting year is £210 million (approximately $284 million at December 31, 2021), of which £11 million (approximately $15 million at December 31, 2021) is our allocated underwriting capacity.

Lloyd's Syndicate 6131. Prior to January 1, 2022, we provided capital to an SPA, Syndicate 6131, which focused on contingency and specialty property business. Effective July 1, 2020, Syndicate 6131 entered into a six-month quota share reinsurance agreement with an unaffiliated insurer. Under this agreement, Syndicate 6131 ceded essentially half of the premium assumed from Syndicate 1729 to the unaffiliated insurer; the agreement was non-renewed on January 1, 2021 and we decreased our participation in the results of Syndicate 6131 to 50% from 100% for the 2021 underwriting year, as previously discussed. Due to the quarter lag, this reduced participation was not reflected in our results until the second quarter of 2021. Syndicate 6131 had a maximum underwriting capacity for the 2021 underwriting year of £20 million (approximately $27 million based on December 31, 2021 exchange rates), of which £10 million (approximately $14 million based on December 31, 2021 exchange rates) was our allocated underwriting capacity. Effective January 1, 2022, Syndicate 6131 ceased underwriting on a quota share basis with Syndicate 1729 as Syndicate 6131's business is retained within Syndicate 1729 beginning with the 2022 underwriting year, as previously discussed. Premium from our participation in the results of Syndicate 6131 from open underwriting years prior to 2022 will continue to earn out pro rata over the entire policy period of the underlying business.

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In addition to the results of our participation in Lloyd's Syndicates, as discussed above, our Lloyd's Syndicates segment also includes 100% of the results of our wholly owned subsidiaries that support our operations at Lloyd's. For the years ended December 31, 2021 and 2020, the results of our Lloyd's Syndicates segment were as follows:

Year Ended December 31
($ in thousands)20212020Change
Net premiums written$31,667$67,652$(35,985)(53.2%)
Net premiums earned$48,372$77,226$(28,854)(37.4%)
Net investment income1,9614,128(2,167)(52.5%)
Net investment gains (losses)249988(739)(74.8%)
Other income912518611,688.2%
Net losses and loss adjustment expenses(29,812)(50,216)20,404(40.6%)
Underwriting, policy acquisition and operating expenses(17,957)(30,136)12,179(40.4%)
Income tax benefit (expense)29(29)nm
Segment results$3,725$2,070$1,65580.0%
Net loss ratio61.6%65.0%(3.4 pts)
Underwriting expense ratio37.1%39.0%(1.9 pts)

Premiums Written

Changes in premium volume within our Lloyd's Syndicates segment are driven by five primary factors: (1) changes in our participation in the Syndicates, (2) the amount of new business and the channels in which the business is written, (3) the retention of existing business, (4) the premium charged for business that is renewed, which is affected by rates charged and by the amount and type of coverage an insured chooses to purchase and (5) the timing of premium written through multi-period policies.

Gross, ceded and net premiums written were as follows:

Year Ended December 31
($ in thousands)20212020Change
Gross premiums written$37,969$84,718$(46,749)(55.2%)
Less: Ceded premiums written6,30217,066(10,764)(63.1%)
Net premiums written$31,667$67,652$(35,985)(53.2%)

Gross Premiums Written

Gross premiums written in 2021 consisted of specialty property coverages (31% of total gross premiums written), property insurance coverages (27%), casualty coverages (26%), contingency coverages (9%), catastrophe reinsurance coverages (5%) and property reinsurance coverages (2%). The decrease in gross premiums written in 2021 as compared to 2020 was primarily driven by our decreased participation in the results of Syndicates 1729 and 6131, partially offset by volume increases on renewal business and renewal pricing increases, primarily on property insurance and casualty coverages and new business written, primarily on specialty property and property insurance coverages.

Ceded Premiums Written

Syndicate 1729 utilizes reinsurance to provide the capacity to write larger limits of liability on individual risks, to provide protection against catastrophic loss and to provide protection against losses in excess of policy limits. As previously discussed, for the second half of 2020 Syndicate 6131 utilized external quota share reinsurance to manage the net loss exposure on the specialty property and contingency coverages it assumed from Syndicate 1729 by ceding essentially half of the premium assumed to an unaffiliated insurer; this agreement was non-renewed on January 1, 2021. Due to the quarter lag, the effect of this six-month reinsurance arrangement began to be reflected in our results in the fourth quarter of 2020. Ceded premiums written decreased for the year ended December 31, 2021 as compared to 2020 primarily driven by our decreased participation in the results of Syndicates 1729 and 6131 and, to a lesser extent, the impact of an increase in estimated reinsurance reinstatement premiums of $1.2 million during the fourth quarter of 2020 triggered by certain property and catastrophe related losses exceeding specified levels in the reinsurance agreement.

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Net Premiums Earned

Net premiums earned consist of gross premiums earned less the portion of earned premiums that the Syndicates cede to reinsurers for their assumption of a portion of losses. Premiums written through open-market channels are generally earned pro rata over the entire policy period, which is predominantly twelve months, whereas premiums written through delegated underwriting authority arrangements are generally earned over the policy period plus twelve months. Therefore, net premiums earned is affected by shifts in the mix of policies written between the open-market and delegated underwriting authority arrangements. Additionally, net premiums earned consists of a mix of policies earned from different open underwriting years. As previously discussed, we participate to a varying degree in each open underwriting year which may cause fluctuations in premiums earned. Furthermore, fluctuations in premiums earned tend to lag those of premiums written. Premiums for certain policies and assumed reinsurance contracts are reported subsequent to the coverage period and/or may be subject to adjustment based on loss experience. These premium adjustments are earned when reported, which can result in further fluctuation in earned premium.

Gross, ceded and net premiums earned were as follows:

Year Ended December 31
($ in thousands)20212020Change
Gross premiums earned$60,590$98,990$(38,400)(38.8%)
Less: Ceded premiums earned12,21821,764(9,546)(43.9%)
Net premiums earned$48,372$77,226$(28,854)(37.4%)

The decrease in net premiums earned for the year ended December 31, 2021 as compared to 2020 was driven by our decreased participation in Syndicates 1729 and 6131, partially offset by the effect of the aforementioned reinstatement premiums earned of $1.2 million during the fourth quarter of 2020.

Net Losses and Loss Adjustment Expenses

Losses for the year were primarily recorded using the loss assumptions by risk category incorporated into the business plans submitted to Lloyd's for Syndicate 1729 and Syndicate 6131 with consideration given to loss experience incurred to date. The assumptions used in each business plan were consistent with loss results reflected in Lloyd's historical data for similar risks. The loss ratios may fluctuate due to the mix of earned premium and the timing of earned premium adjustments (see discussion in this section under the heading "Net Premiums Earned"). Premium and exposure for some of Syndicate 1729's insurance policies and reinsurance contracts are initially estimated and subsequently adjusted over an extended period of time as underlying premium reports are received from cedents and insureds. When reports are received, the premium, exposure and corresponding loss estimates are revised accordingly. Changes in loss estimates due to premium or exposure fluctuations are incurred in the accident year in which the premium is earned.

The following table summarizes calendar year net loss ratios by separating losses between the current accident year and all prior accident years. Net loss ratios for the period were as follows:

Year Ended December 31
20212020Change
Calendar year net loss ratio61.6%65.0%(3.4pts)
Less impact of prior accident years on the net loss ratio9.7%0.8%8.9pts
Current accident year net loss ratio51.9%64.2%(12.3pts)

For the year ended December 31, 2021, the current accident year net loss ratio decreased 12.3 percentage points as compared to 2020. The decrease in the current accident year net loss ratio was primarily driven by higher reinsurance recoveries as a proportion of gross losses as compared to the prior year period, partially offset by certain catastrophe related losses.

We recognized $4.7 million and $0.6 million of unfavorable prior year development for the years ended December 31, 2021 and 2020, respectively. The unfavorable prior year development for the year ended December 31, 2021 was driven by higher than expected losses and development on certain large claims, primarily catastrophe related losses.

We have exposures to potential COVID-19 claims through our participation in Syndicates 1729 and 6131. During 2021, we recognized losses related to COVID-19 of approximately $1.6 million, net of reinsurance, as compared to $3.6 million during 2020, primarily in Syndicate 6131's contingency and Syndicate 1729's casualty books of business. See previous discussion in Part I, Item 1 under the heading "Insurance Regulatory Matters- COVID-19."

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Underwriting, Policy Acquisition and Operating Expenses

Underwriting, policy acquisition and operating expenses decreased by $12.2 million for the year ended December 31, 2021 as compared to 2020 and reflected our decreased participation in Syndicate 1729 and Syndicate 6131.

For the year ended December 31, 2021, the underwriting expense ratio decreased by 1.9 percentage points as compared to 2020 which primarily reflected the impact of our reduced participation in Syndicate 1729 and Syndicate 6131. Operating expenses incurred during 2021 primarily were related to the 2021 underwriting year for which our participation is 5% and 50% in Syndicate 1729 and Syndicate 6131, respectively, whereas the net premiums earned during the same period also includes premium from other open underwriting years in which we participate at a higher degree.

Investments

Syndicate 1729's fixed maturity portfolio includes certain debt securities classified as trading securities. Investment results associated with these fixed maturity trading securities are reported on the same quarter lag. The decrease in net investment income in 2021 as compared to 2020 was primarily attributable to lower average investment balances and lower yields, primarily from investment-grade corporate debt securities. The lower average investment balance in 2021 was driven by the return of approximately $32.3 million of cash and cash equivalents from our FAL balances during the third quarter of 2020 given the reduction in our participation in the results of Syndicate 1729 to 29% from 61% for the 2020 underwriting year. In addition, we received a return of approximately $24.5 million and $8.0 million of cash from our FAL balances during the second and fourth quarters of 2021, respectively, given the additional reduction in our participation in the results of Syndicate 1729 and Syndicate 6131 for the 2021 underwriting year, as previously discussed. Further, during the fourth quarter of 2021, we received a return of approximately $26.6 million of cash from our FAL balances given the decision to incorporate Syndicate 6131's business into Syndicate 1729 for the 2022 underwriting year, as previously discussed. Our lower FAL balances will continue to impact the segment's net investment income in future periods.

Taxes

The results of this segment are subject to U.K. income tax law.

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Segment Results - Corporate

Our Corporate segment includes our investment operations, including the investment operations of NORCAL since the date of acquisition and excludes those reported in our Segregated Portfolio Cell Reinsurance and Lloyd's Syndicates segments as discussed in Note 18 of the Notes to Consolidated Financial Statements. In addition, this segment includes corporate expenses, interest expense, U.S. income taxes and non-premium revenues generated outside of our insurance entities. Segment results for the year ended December 31, 2021 exclude transaction-related costs and the associated income tax benefit related to the NORCAL acquisition as we do not consider these items in assessing the financial performance of the segment (Note 2 of the Notes to Consolidated Financial Statements provides additional information regarding this acquisition). Segment results for our Corporate segment were net earnings of $91.2 million and $71.4 million for the years ended December 31, 2021 and 2020, respectively, and included the following:

Year Ended December 31
($ in thousands)20212020Change
Net investment income$67,747$66,786$9611.4%
Equity in earnings (loss) of unconsolidated subsidiaries$48,974$(11,921)$60,895510.8%
Net investment gains (losses)$19,981$11,605$8,37672.2%
Other income$5,531$2,531$3,000118.5%
Operating expense$26,641$23,429$3,21213.7%
Interest expense$19,719$15,503$4,21627.2%
Income tax expense (benefit)$4,651$(41,300)$45,951111.3%

Net Investment Income, Equity in Earnings (Loss) of Unconsolidated Subsidiaries, Net Investment Gains (Losses)

Net Investment Income

Net investment income is primarily derived from the income earned by our fixed maturity securities and also includes dividend income from equity securities, income from our short-term and cash equivalent investments, earnings from other investments and increases in the cash surrender value of BOLI contracts, net of investment fees and expenses. Net investment income in 2021 also includes income earned, net of investment fees and expenses, since the date of acquisition from investments acquired from NORCAL .

Net investment income by investment category was as follows:

Year Ended December 31
($ in thousands)20212020Change
Fixed maturities$71,451$64,338$7,11311.1%
Equities2,5394,369(1,830)(41.9%)
Short-term investments, including Other1,8602,209(349)(15.8%)
BOLI2,6992,02367633.4%
Investment fees and expenses(10,802)(6,153)(4,649)75.6%
Net investment income$67,747$66,786$9611.4%

Fixed Maturities

Income from our fixed maturities increased in 2021 as compared to 2020 driven by higher average investment balances primarily attributable to the addition of fixed maturity securities valued at $1.1 billion to our portfolio on May 5, 2021 as a result of the NORCAL acquisition (see Note 2 of the Notes to Consolidated Financial Statements for additional information). The increase in income from our fixed maturities in 2021 was partially offset by lower yields from our corporate debt securities and the impact of capital planning in anticipation of closing the NORCAL acquisition. As a result of the NORCAL acquisition, average investment balances were approximately 51% higher for 2021 as compared to 2020; excluding the impact of the acquisition, average investment balances were approximately 10% higher.

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Average yields for our fixed maturity portfolio were as follows:

Year Ended December 31
20212020
Average income yield2.3%3.1%
Average tax equivalent income yield2.3%3.1%

Yields on fixed maturity securities decreased in 2021 as compared to 2020. The decrease in 2021 was primarily driven by the application of GAAP purchase accounting rules whereby all NORCAL fixed maturity securities acquired were valued at fair value on the date of acquisition resulting in lower average yields on those securities as compared to the average yields on our other securities.

Equities

Income from our equity portfolio decreased in 2021 as compared to 2020 due to a decrease in our allocation to this asset category during the first half of 2021 and, to a lesser extent, the reallocation in our mix of securities within this asset category.

Short-term Investments and Other Investments

Short-term investments, which have a maturity at purchase of one year or less are carried at fair value, which approximates their cost basis, and are primarily composed of investments in U.S. treasury obligations, commercial paper and money market funds. Income from our short-term and other investments decreased during 2021 primarily attributable to lower yields given the actions taken by the Federal Reserve to aggressively reduce interest rates in response to COVID-19, partially offset by income contributed by investments acquired from NORCAL.

BOLI

We hold BOLI policies that are carried at the current cash surrender value of the policies, which includes the BOLI policies acquired from NORCAL. All insured individuals were members of ProAssurance or NORCAL management at the time the policies were acquired. Income from our BOLI policies increased in 2021 as compared to 2020 primarily attributable to the addition of BOLI policies valued at $10 million to our portfolio on May 5, 2021 as a result of the NORCAL acquisition.

Investment Fees and Expenses

Investment fees and expenses increased in 2021 as compared to 2020 driven by additional costs associated with our investments acquired from NORCAL since the date of acquisition.

Equity in Earnings (Loss) of Unconsolidated Subsidiaries

Equity in earnings (loss) of unconsolidated subsidiaries was comprised as follows:

Year Ended December 31
($ in thousands)20212020Change
All other investments, primarily investment fund LPs/LLCs$64,031$7,855$56,176715.2%
Tax credit partnerships(15,057)(19,776)4,719(23.9%)
Equity in earnings (loss) of unconsolidated subsidiaries$48,974$(11,921)$60,895510.8%

We hold interests in certain LPs/LLCs that generate earnings from trading portfolios, secured debt, debt securities, multi-strategy funds and private equity investments. The performance of the LPs/LLCs is affected by the volatility of equity and credit markets. For our investments in LPs/LLCs, we record our allocable portion of the partnership operating income or loss as the results of the LPs/LLCs become available, typically following the end of a reporting period. The increase in our investment results from our portfolio of investments in LPs/LLCs for 2021 as compared to 2020 was due to higher earnings from several LPs/LLCs and the prior year effect of the volatility in global financial markets related to COVID-19. Our investment results from our portfolio of investments in LPs/LLCs in 2021 included additional earnings of approximately $1.4 million from acquired interests in four LPs as a result of the NORCAL acquisition; given the results of our investments in LPs/LLCs are often reported to us on a one quarter lag, the earnings from these investments were not reflected in our results until the third quarter of 2021.

Our tax credit partnership investments are designed to generate returns in the form of tax credits and tax-deductible project operating losses and are comprised of qualified affordable housing project tax credit partnerships and a historic tax credit partnership. We account for our tax credit partnership investments under the equity method and record our allocable portion of the operating losses of the underlying properties based on estimates provided by the partnerships. For our qualified affordable housing project tax credit partnerships, we adjust our estimates of our allocable portion of operating losses

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periodically as actual operating results of the underlying properties become available. The primary benefits of tax credits and tax-deductible operating losses from the historic tax credit partnerships are earned in a short period with potential for additional cash flows extending over several years. The results from our tax credit partnership investments for the year ended December 31, 2021 reflected lower partnership operating losses as compared to 2020. In addition, based on results received, we increased our estimate of operating losses by $1.9 million and $4.3 million for the years ended December 31, 2021 and 2020, respectively.

The tax benefits received from our tax credit partnerships, which are not reflected in our investment results, reduced our tax expense in 2021 and 2020 as follows:

Year Ended December 31
(In millions)20212020
Tax credits recognized during the period$13.2$17.9
Tax benefit of tax credit partnership operating losses$3.2$4.2

The tax credits generated from our tax credit partnership investments of $13.2 million for 2021 were deferred for use in future periods due to the utilization of NOLs available to us following our acquisition of NORCAL. For the year ended December 31, 2020, due to our consolidated pre-tax loss, the tax credits generated from our tax credit partnership investments of $17.9 million were deferred to be utilized in future periods. For the year ended December 31, 2021, we utilized approximately $2.0 million of tax credits carried forward from 2019 and, as of December 31, 2021, we had approximately $46.7 million of available tax credit carryforwards generated from our investments in tax credit partnerships which we expect to utilize in future years. See further discussion in Note 7 of the Notes to Consolidated Financial Statements.

Tax credits provided by the underlying projects of our historic tax credit partnership are typically available in the tax year in which the project is put into active service, whereas the tax credits provided by qualified affordable housing project tax credit partnerships are provided over approximately a ten year period.

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Non-GAAP Financial Measure – Tax Equivalent Investment Result

We believe that to fully understand our investment returns it is important to consider the current tax benefits associated with certain investments as the tax benefit received represents a portion of the return provided by our tax-exempt bonds, BOLI, common and preferred stocks, and tax credit partnership investments (collectively, our tax-preferred investments). We impute a pro forma tax-equivalent result by estimating the amount of fully-taxable income needed to achieve the same after-tax result as is currently provided by our tax-preferred investments. We believe this better reflects the economics behind our decision to invest in certain asset classes that are either taxed at lower rates and/or result in reductions to our current federal income tax expense. Our pro forma tax-equivalent investment result is shown in the table that follows as well as a reconciliation of our GAAP net investment result to our tax equivalent result.

Year Ended December 31
(In thousands)20212020
GAAP net investment result:
Net investment income$67,747$66,786
Equity in earnings (loss) of unconsolidated subsidiaries48,974(11,921)
GAAP net investment result$116,721$54,865
Pro forma tax-equivalent investment result$120,450$56,088
Reconciliation of pro forma and GAAP tax-equivalent investment result:
GAAP net investment result$116,721$54,865
Taxable equivalent adjustments, calculated using the 21% federal statutory tax rate
State and municipal bonds522595
BOLI717538
Dividends received1290
Tax credit partnerships*2,478
Pro forma tax-equivalent investment result$120,450$56,088
* Due to the realized NOL for the years ended December 31, 2021 and December 31, 2020, the tax credits recognized from our tax credit partnership investments, during each of those respective years, were deferred to be utilized in future periods, however during the year ended December 31, 2021, we utilized a portion of the tax credits carried forward from the 2019 tax year.

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Net Investment Gains (Losses)

The following table provides detailed information regarding our net investment gains (losses).

Year Ended December 31
(In thousands)20212020
Total impairment losses
Corporate debt$$(1,745)
Portion of impairment losses recognized in other comprehensive income before taxes:
Corporate debt237
Net impairment losses recognized in earnings(1,508)
Gross realized gains, available-for-sale fixed maturities13,04713,436
Gross realized (losses), available-for-sale fixed maturities(1,133)(2,499)
Net realized gains (losses), equity investments5,39412,965
Net realized gains (losses), other investments8,6603,883
Change in unrealized holding gains (losses), equity investments(4,697)(18,926)
Change in unrealized holding gains (losses), convertible securities, carried at fair value as a part of other investments(1,701)3,850
Other411404
Net investment gains (losses)$19,981$11,605

We did not recognize any credit-related impairment losses in earnings or non-credit impairment losses in OCI for the year ended December 31, 2021. For the year ended December 31, 2020, we recognized $1.5 million of credit-related impairment losses in earnings and a nominal amount of non-credit impairment losses in OCI. The credit-related impairment losses recognized in 2020 primarily related to corporate bonds in the energy and consumer sectors. Additionally, 2020 included credit-related impairment losses related to four corporate bonds in various sectors, which were sold during 2020. The non-credit impairment losses recognized during 2020 related to three corporate bonds in the energy and consumer sectors.

We recognized $20.0 million of net investment gains for the year ended December 31, 2021 which include approximately $1.9 million of net investment gains related to investments acquired from NORCAL. Net investment gains in 2021 were driven by realized gains on the sale of certain available-for-sale fixed maturities and other investments, partially offset by unrealized holding losses resulting from decreases in the fair value on our equity portfolio. We recognized $11.6 million of net investment gains for the year ended December 31, 2020, driven primarily by realized gains on the sale of certain available-for-sale fixed maturities and equity investments, partially offset by unrealized holding losses resulting from decreases in the fair value on our equity portfolio due to the volatility in the global financial markets related to COVID-19.

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Operating Expenses

Corporate segment operating expenses were comprised as follows:

Year Ended December 31
($ in thousands)20212020Change
Operating expenses$36,007$37,562$(1,555)(4.1%)
Management fee offset(9,366)(14,133)4,767(33.7%)
Total$26,641$23,429$3,21213.7%

Operating expenses decreased during the year ended December 31, 2021 as compared to 2020 primarily due to a decrease in professional fees and, to a lesser extent, the prior year effect of $0.5 million of one-time expenses incurred in 2020, partially offset by an increase in compensation-related costs. The decrease in professional fees in 2021 was driven by a decrease in corporate legal expenses. One-time expenses in 2020 were primarily comprised of employee severance and early retirement benefits granted to certain employees. The increase in compensation-related costs during 2021 was driven by higher amounts accrued for performance-related incentive plans due to our improved performance metrics and, to a lesser extent, an increase in share-based compensation expenses attributable to the effect of an increase in the value of projected awards in 2021 based upon the improvement of the associated performance metrics.

Operating subsidiaries within our Specialty P&C segment (excluding the acquired operating subsidiaries of NORCAL) and our Workers' Compensation Insurance segment are charged a management fee by the Corporate segment for services provided to these subsidiaries. The management fee is based on the extent to which services are provided to the subsidiary and the amount of premium written by the subsidiary. Under the arrangement, the expenses associated with such services are reported as expenses of the Corporate segment, and the management fees charged are reported as an offset to Corporate operating expenses. Fluctuations in the amount of premium written by each subsidiary can result in corresponding variations in the management fee charged to each subsidiary during a particular period. Due to organizational structure enhancements in our Specialty P&C segment during 2020, the extent to which services are provided by the Corporate segment to the operating subsidiaries within that segment decreased effective January 1, 2021. Accordingly, we reduced the fee charged to the operating subsidiaries within the Specialty P&C segment during 2021. There were no changes to the extent to which services are provided by the Corporate segment to the operating subsidiaries within our Workers' Compensation Insurance segment in 2021.

Interest Expense

Consolidated interest expense for the years ended December 31, 2021 and 2020 was comprised as follows:

Year Ended December 31
($ in thousands)20212020Change
Senior Notes due 2023$13,429$13,429$%
Contribution Certificates (including accretion)*5,0465,046nm
Revolving Credit Agreement (including fees and amortization)1,12083128934.8%
Mortgage Loans (including amortization)444812(368)(45.3%)
(Gain)/loss on interest rate cap(320)431(751)(174.2%)
Interest expense$19,719$15,503$4,21627.2%
*Includes accretion of approximately $1.2 million for the year ended December 31, 2021 which is recorded as an increase to interest expense as a result of the difference between the recorded acquisition date fair value and the principal balance of the Contribution Certificates associated with our acquisition of NORCAL.

Consolidated interest expense increased during 2021 as compared to 2020 driven by the addition of interest expense on the Contribution Certificates associated with our acquisition of NORCAL (See Note 2 and Note 13 of the Notes to Consolidated Financial Statements) and, to a lesser extent, an increase in the borrowings on our Revolving Credit Agreement. During the third quarter of 2021, we repaid the balance outstanding on the Revolving Credit Agreement of $15.0 million and there were no outstanding borrowings on this agreement during 2020; interest expense on the Revolving Credit Agreement in both 2021 and 2020 primarily reflected unused commitment fees. The increase in consolidated interest expense for 2021 was partially offset by lower interest expense on our Mortgage Loans. In 2021, we repaid the balance outstanding on our Mortgage Loans of $35.3 million; interest expense on the Mortgage Loans during the current period included the write-off of the related unamortized debt issuance costs which were nominal in amount. In addition, consolidated interest expense during 2021 was impacted by the change in the fair value of our interest rate cap.

See further discussion of our interest rate cap agreement in Note 3 and further discussion on our outstanding debt in Note 13 of the Notes to Consolidated Financial Statements.

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Taxes

Tax expense allocated to our Corporate segment includes U.S. tax only, which would include U.S. tax expense incurred from our corporate membership in Lloyd's of London. The U.K. tax expense incurred by the U.K. based subsidiaries of our Lloyd's Syndicates segment is allocated to that segment. The SPCs at Inova Re, one of our Cayman Islands reinsurance subsidiaries, have each made a 953(d) election under the U.S. Internal Revenue Code and are subject to U.S. federal income tax; therefore, tax expense allocated to our Corporate segment also includes tax expense incurred from any SPC at Inova Re in which we have a participation interest of 80% or greater as those SPCs are required to be included in our consolidated tax return. Consolidated tax expense (benefit) reflects the tax expense (benefit) of both segments and the tax impact of items excluded from segment reporting, as shown in the table below:

Year Ended December 31
(In thousands)20212020
Corporate segment income tax expense (benefit)$4,651$(41,300)
Lloyd's Syndicates segment income tax expense (benefit)(29)
Income tax expense (benefit) - transaction-related costs*(2,168)
Consolidated income tax expense (benefit)$2,483$(41,329)
*Represents the income tax benefit associated with the transaction-related costs related to our acquisition of NORCAL that are not included in a segment as we do not consider these costs in assessing the financial performance of any of our operating or reportable segments. See Note 18 of the Notes to Consolidated Financial Statements for a reconciliation of our segment results to our consolidated results.

Listed below are the primary factors affecting our consolidated effective tax rate for the years ended December 31, 2021 and 2020. The comparability of each factor's impact on our effective tax rate is affected by the consolidated pre-tax income recognized during 2021 as compared to the consolidated pre-tax loss recognized during 2020. Factors that have the same directional impact on income tax expense (benefit) in each period have an opposite impact on our effective tax rate due to the effective tax rate being calculated based upon a pre-tax income during the year ended December 31, 2021 versus the pre-tax loss during the year ended December 31, 2020. These factors include the following:

Year Ended December 31
20212020
($ in thousands)Income tax (benefit) expenseRate ImpactIncome tax (benefit) expenseRate Impact
Computed "expected" tax expense (benefit) at statutory rate$30,78721.0%$(45,582)21.0%
Tax-exempt income (1)(1,298)(0.9%)(976)0.4%
Tax credits(13,160)(9.0%)(17,876)8.2%
Non-U.S. operating results(1,322)(0.9%)(1,307)0.6%
Tax deficiency (excess tax benefit) on share-based compensation2860.2%457(0.2%)
Tax rate differential on loss carryback%(7,758)3.6%
Goodwill impairment (2)%31,413(14.5%)
Non-taxable gain on bargain purchase (3)(15,626)(10.7%)%
Provision-to-return and other differences3,5742.4%1,217(0.5%)
Change in uncertain tax positions(1,909)(1.3%)(1,674)0.8%
State income taxes4600.3%(561)0.3%
Other6910.6%1,318(0.7%)
Total income tax expense (benefit)$2,4831.7%$(41,329)19.0%

(1) Includes tax-exempt interest, dividends received deduction and change in cash surrender value of BOLI.

(2) Represents the tax impact of the impairment of non-deductible goodwill in relation to the Specialty P&C reporting unit during the third quarter of 2020 (see further discussion on the impairment charge in the Critical Accounting Estimates section under the heading "Goodwill / Intangibles" and in Note 8 of the Notes to Consolidated Financial Statements).

(3) Represents the tax impact of the non-taxable gain on bargain purchase as a result of our acquisition of NORCAL on May 5, 2021. See further discussion on the gain on bargain purchase in Note 2 of the Notes to Consolidated Financial Statements.

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Our effective tax rates for 2021 and 2020, as shown in the table above, differed from the statutory federal income tax rate of 21% in each respective year. The most significant item impacting our effective tax rate for 2021 was the gain on bargain purchase of $74.4 million related to the NORCAL acquisition, all of which was non-taxable. See further discussion on the gain on bargain purchase in Note 2 of the Notes to Consolidated Financial Statements. Additionally, our effective tax rates for both 2021 and 2020 include the benefit recognized from the tax credits transferred to us from our tax credit partnership investments. Tax credits recognized for the year ended December 31, 2021 were $13.2 million as compared to $17.9 million in 2020. While projected tax credits for 2021 are less than 2020, they continue to have a significant impact on the effective tax rate for 2021. For 2020, our effective tax rate was also affected by the additional statutory tax rate differential of 14% on the carryback of our 2020 and 2019 NOLs to the 2015 and 2014 tax years, respectively, as a result of changes made by the CARES Act to the NOL provisions of the tax law. Furthermore, our pre-tax loss in 2020 included a $161.1 million goodwill impairment recognized in relation to the Specialty P&C reporting unit during the third quarter of 2020. Of the $161.1 million goodwill impairment, $149.6 million was non-deductible for which no tax benefit was recognized, while the remaining $11.5 million was deductible for which a 21% tax benefit was recognized on the related income tax amortization. Consequently, the total impact of the goodwill impairment on the effective tax rate in 2020 was approximately 14.5%. See further discussion on this goodwill impairment in Notes 1 and 8 of the Notes to Consolidated Financial Statements.

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