WESTLAKE CORP (WLK)

Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations

Overview

We are a vertically integrated global manufacturer and marketer of performance and essential materials and housing and infrastructure products. We operate in two principal operating segments, Performance and Essential Materials and Housing and Infrastructure Products. The Performance and Essential Materials segment includes Westlake North American Vinyls, Westlake North American Chlor-alkali & Derivatives, Westlake European & Asian Chlorovinyls, Westlake Olefins, Westlake Polyethylene and Westlake Epoxy. The Housing and Infrastructure Products segment includes Westlake Royal Building Products, Westlake Pipe & Fittings, Westlake Global Compounds and Westlake Dimex. We are highly integrated along our materials chain with significant downstream integration from ethylene and chlor-alkali (chlorine and caustic soda) into vinyls, polyethylene, epoxy and styrene monomer. We also have substantial downstream integration from polyvinyl chloride ("PVC") into our building products, PVC pipes and fittings and PVC compounds in our Housing and Infrastructure Products segment.

Since 2022, our European businesses have been impacted by higher energy prices, inflation and reduced demand. Our North American businesses, where we derive a significant portion of our revenue, have also experienced the impacts of high energy costs and interest rates and slower demand for most of our products since the second half of 2022. However, since the second half of 2023, we have experienced lower energy costs in Europe and North America as prices for electricity and natural gas have declined following the elevated 2022 levels and inflation has eased since the 2022 levels, although it still remains a concern. In the near term, we expect that the volatility in energy prices, higher interest rates, inflation and other macroeconomic conditions will continue to impact margins and demand for most of our products.

Recent Developments

Antidumping and Countervailing Duty Investigations

In April 2024, the U.S. Epoxy Resin Producers Ad Hoc Coalition (the "Coalition"), of which we are a member, filed petitions with the U.S. Department of Commerce and the U.S. International Trade Commission requesting the initiation of antidumping investigations regarding imports of certain epoxy resins from China, India, South Korea, Taiwan, and Thailand and countervailing duty investigations regarding imports of the same products from China, India, South Korea, and Taiwan. In September 2024, the U.S. Department of Commerce published its preliminary countervailing duty determination and imposed provisional duties. In November 2024, the U.S. Department of Commerce published its preliminary antidumping determination of dumping margins. The U.S. Department of Commerce is continuing its antidumping and countervailing duty investigations, and the U.S. International Trade Commission is conducting its final phase injury investigation. The investigations are expected to conclude in May 2025.

In June 2024, the Coalition confidentially lodged an antidumping complaint with the European Commission requesting the initiation of an antidumping investigation concerning imports of epoxy resins into the European Union market originating in China, South Korea, Taiwan and Thailand. In July 2024, the European Commission published in the EU Official Journal a notice initiating an antidumping investigation concerning imports of epoxy resins originating in China, South Korea, Taiwan, and Thailand. In October 2024, the European Commission published a regulation requiring registration of imports subject to the investigation. The European Commission is expected to impose provisional duties in late February 2025 and conclude the investigation by late August 2025.

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AC and ECH Pernis Units

In July 2024, the Company approved a plan to temporarily cease operations ("mothball") of the allyl chloride (AC) and epichlorohydrin (ECH) units at the Company's site in Pernis, the Netherlands (collectively, the "Units"). The Company continues to operate the liquid epoxy resin (LER) and bisphenol A (BPA) units at the Pernis facility. The Units are expected to temporarily cease operations in 2025. During 2024, the Company accrued expenses of approximately $75 million related to mothballing of the Units that consisted of charges for environmental remediation and other plant mothballing expenses of approximately $71 million and of employee severance and separation expenses of approximately $4 million. Once the mothballing is completed, the Company expects these actions will improve the financial performance of the Pernis, Netherlands site while enabling the Company to continue to serve its customers with BPA, LER, solutions, and epoxy specialty resins.

Louisiana Tax Reform Bills

On December 4, 2024, the Governor of Louisiana signed into law a package of tax reform bills, effective January 1, 2025 and January 1, 2026. Among other things, the laws reduce the corporate state income tax rate, repeal the corporate state franchise tax, and eliminate preferential apportionment treatment for companies with sales and inventory in foreign trade zones. In the fourth quarter of 2024, we recognized a one-time charge of approximately $45 million for the revaluation of state deferred tax assets and deferred tax liabilities associated with the change in corporate state income tax and apportionment rates resulting from this change. The Company will continue to evaluate the impact of these tax law changes.

Our Operations and Outlook

Performance and Essential Materials

Our performance and essential materials such as ethylene, PVC, polyethylene, epoxy and caustic soda are some of the most widely used materials in the world and are upgraded into a wide variety of higher value-added products used in many end-markets. Westlake is the second-largest chlor-alkali producer and the second-largest PVC producer in the world, which makes Westlake a leading global chlorovinyls producer. Our performance and essential materials are used by customers in PVC pipe applications; housing and construction products; food and specialty packaging; industrial and consumer packaging; renewable wind energy; coatings; consumer durables; medical health applications; and mobility and transportation. Chlor-alkali and petrochemicals are typically manufactured globally in large volume by a number of different producers using widely available technologies. The chlor-alkali and petrochemical industries exhibit cyclical commodity characteristics, and margins are influenced by changes in the balance between global supply and demand and the resulting operating rates, the level of general economic activity and the price of raw materials. Due to the significant size of new plants, capacity additions are built in large increments and typically require several years of demand growth to be absorbed. The cycle is generally characterized by periods of tight supply, leading to high operating rates and margins, followed by a decline in operating rates and margins primarily as a result of excess new capacity additions. Westlake is a leading supplier of liquid and solid epoxy resins that are used in a wide variety of industrial coating applications. We are also one of the leading producers of epoxy specialty resins, modifiers and curing agents in Europe, the United States and Asia with a global reach to our end markets. Epoxy resins are the fundamental component of many types of materials and are often used in the automotive, construction, wind energy, aerospace and electronics industries due to their superior adhesion, strength and durability.

Global demand for most of our products started to recover from the effects of the COVID-19 pandemic in the second half of 2020 and remained strong through the first half of 2022. However, since the second half of 2022 and during the early part of 2023, we saw significant volatility in natural gas and electricity costs, particularly in Europe, as well as in ethane and ethylene prices. We have experienced a decline in natural gas and electricity costs since the second half of 2023 through the third quarter of 2024 and seasonal price increase in the fourth quarter of 2024. Since the first half of 2022, we have continued to experience lower prices and weak demand for most of our products globally. The ongoing conflict between Russia and Ukraine since Russia's invasion of Ukraine in 2022, the conflict in the Middle East, slow economic growth in China, increase in bisphenol-A, epichlorohydrin and base epoxy resin exports out of Asia into European and North American markets, disruption of trade flows due to enactment of duties and tariffs, timing of certain new ethylene and polyethylene capacity additions in North America, Asia, and the Middle East, volatility in natural gas and electricity prices and volatility in crude oil prices could have a continuing negative impact on the performance of Performance and Essential Materials businesses.

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We purchase significant amounts of ethane feedstock, natural gas, ethylene and salt from external suppliers for use in production of performance and essential materials. We also purchase significant amounts of electricity to supply the energy required in our production processes. While we have agreements providing for the supply of ethane feedstock, natural gas, ethylene, salt and electricity, the contractual prices for these raw materials and energy vary with market conditions and may be highly volatile. Factors that have caused volatility in our raw material prices in the past, and which may do so in the future include:

•the availability of feedstock from shale gas and oil drilling;

•supply and demand for crude oil and natural gas;

•shortages of raw materials due to increasing demand;

•ethane and liquefied natural gas exports;

•capacity constraints due to higher construction costs for investments, construction delays, strike action or involuntary shutdowns;

•the general level of business and economic activity; and

•the direct or indirect effect of governmental regulation.

Significant volatility in raw material costs tends to put pressure on product margins as sales price increases could lag behind raw material cost increases. Conversely, when raw material costs decrease, customers may seek immediate relief in the form of lower sales prices. We currently use derivative instruments to reduce price volatility risk on feedstock commodities and lower overall costs. Normally, there is a pricing relationship between a commodity that we process and the feedstock from which it is derived. When this pricing relationship deviates from historical norms, we have from time to time entered into derivative instruments and physical positions in an attempt to take advantage of this relationship.

Our historical results have been significantly affected by our plant production capacity, our efficient use of that capacity and our ability to increase capacity. Since our inception, we have followed a disciplined growth strategy that focuses on plant acquisitions, new plant construction and internal expansion. We evaluate each expansion project on the basis of its ability to produce sustained returns in excess of our cost of capital and its ability to improve efficiency or reduce operating costs. We also regularly look at acquisition opportunities that would be consistent with, or complimentary to, our overall business strategies. Depending on the size of the acquisition, any such acquisitions could require external financing.

As noted above in Item 1A, "Risk Factors," we are subject to extensive environmental regulations, which may impose significant additional costs on our operations in the future. Further, concerns about greenhouse gas emissions and their possible effects on climate change has led to the enactment of regulations, and to proposed legislation and additional regulations, that could affect us in the form of increased cost of feedstocks and fuel, other increased costs of production and decreased demand for our products. While we do not expect any of these enactments or proposals to have a material adverse effect on us in the near term, we cannot predict the longer-term effect of any of these regulations or proposals on our future financial condition, results of operations or cash flows.

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Housing and Infrastructure Products

Our Housing and Infrastructure Products segment is primarily comprised of residential building products, PVC pipes and fittings and PVC compound products. Our sales are affected by new home constructions and home repair and remodeling as well as the decisions of distributors and dealers on the levels of inventory they carry, their views on product demand, their financial condition and the manner in which they choose to manage inventory risk. A significant portion of our performance in this segment is driven by the activities in the residential construction and repair and remodeling markets in North America, which began to decline at the end of the second quarter of 2022 primarily due to the negative effect that rising mortgage rates in the United States had on buyer sentiment. Since the beginning of 2024, with the stabilization of interest rates and the possibility of further interest rate cuts by the U.S. Federal Reserve in the near term, we have seen improvement in the demand for housing products. Performance of our housing and infrastructure products businesses over time are generally reflective of the trends of building permits and housing starts in the New Residential Construction Survey by the U.S. Census Bureau and the Repair and Remodeling Index (RRI) provided by the National Association of Home Builders (the "NAHB") among others. Although we ultimately expect that the Infrastructure Investment and Jobs Act of 2021 and historically low residential housing construction that has resulted in an undersupply of existing housing may have a favorable long-term impact on our Housing and Infrastructure Products segment, the current inflationary environment impacting consumer spending and priorities and decade-high mortgage interest rates impacting consumer affordability are expected to have an unfavorable impact on the demand for housing construction in the near term and, as a result, our products produced by this segment.

The following table presents annual historical housing starts per the U.S. Census Bureau and the 2025 and 2026 outlook per the NAHB:

North American PVC facilities within the Performance and Essential Materials segment supply most of the PVC required for our building products and PVC pipes and fittings plants. Our raw materials for stone, roofing and accessories, windows, shutters and specialty tool products are externally purchased. PVC required for the PVC compounds plants is either internally sourced from our North American, European and Asian facilities within the Performance and Essential Materials segment or externally purchased based on the location of the plants. The remaining feedstocks required, including pigments, fillers, stabilizers and other ingredients, are purchased under short-term contracts based on prevailing market prices.

Factors that have caused volatility in our raw material prices, energy costs and production processes in the past, and which may do so in the future, include significant fluctuation in prices of these raw materials in response to, among other things, variable worldwide supply and demand across different industries, speculation in commodities futures, general economic, business or environmental conditions, labor costs, competition, import duties impacting our cross-border trades within North America, tariffs, worldwide currency fluctuations, freight, inflationary pressures, regulatory costs, and product and process evolutions that impact demand for the same materials. Increasing raw material prices directly impact our cost of sales and our ability to maintain margins depends on implementing price increases in response to increasing raw material costs. The market for our products may or may not accept price increases, and as such, our future financial condition, results of operations or cash flows could be materially impacted.

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Non-GAAP Financial Measures

The body of accounting principles generally accepted in the United States is commonly referred to as "GAAP." For this purpose, a non-GAAP financial measure is generally defined by the Securities and Exchange Commission ("SEC") as one that purports to measure historical or future financial performance, financial position or cash flows that (1) excludes amounts, or is subject to adjustments that have the effect of excluding amounts, that are included in the most directly comparable measure calculated and presented in accordance with GAAP in the statement of income, balance sheet or statement of cash flows (or equivalent statements) of the registrant; or (2) includes amounts, or is subject to adjustments that have the effect of including amounts, that are excluded from the most directly comparable measure so calculated and presented. In this report, we disclose non-GAAP financial measures, primarily earnings before interest, taxes, depreciation and amortization ("EBITDA") and Free Cash Flow. We define EBITDA as net income before interest expense, income taxes, depreciation and amortization. We define Free Cash Flow as net cash provided by operating activities less additions to property, plant and equipment. The non-GAAP financial measures described in this Form 10-K are not substitutes for the GAAP measures of earnings and cash flows.

EBITDA is included in this Form 10-K because our management considers it an important supplemental measure of our performance and believes that it is frequently used by securities analysts, investors and other interested parties in the evaluation of companies in our industry, some of which present EBITDA when reporting their results. We regularly evaluate our performance as compared to other companies in our industry that have different financing and capital structures and/or tax rates by using EBITDA. In addition, we utilize EBITDA in evaluating acquisition targets. Management also believes that EBITDA is a useful tool for measuring our ability to meet our future debt service and satisfy capital expenditure and working capital requirements, and EBITDA is commonly used by us and our investors to measure our ability to service indebtedness.

Free Cash Flow is included in this Form 10-K because our management considers it an important supplemental measure of our performance and believes that it is frequently used by securities analysts, investors and other interested parties in the evaluation of companies in our industry, some of which present Free Cash Flow when reporting their results. We regularly evaluate our performance as compared to other companies in our industry that have different financing and capital structures and/or tax rates by using Free Cash Flow. Management also believes that Free Cash Flow is useful to investors and securities analysts to evaluate our liquidity, evaluate strategic investment, evaluate our stock buyback plan and measure our ability to meet our future debt service.

EBITDA and Free Cash Flow are not substitutes for the GAAP measures of net income, income from operations and net cash provided by operating activities and are not necessarily measures of our ability to fund our cash needs. In addition, companies calculate EBITDA and Free Cash Flow differently and, therefore, EBITDA and Free Cash Flow as presented for us may not be comparable to EBITDA and Free Cash Flow reported by other companies. EBITDA has material limitations as a performance measure because it excludes interest expense, depreciation and amortization and income taxes. Free Cash Flow has material limitations as a performance measure because it only considers net cash provided by operating activities, and not net income or income from operations. For instance, it applies the entire cost of capital expenditure in the period in which the property or equipment is acquired, rather than spreading it over several periods as is the case with net income and income from operations.

Reconciliations of EBITDA to net income, income from operations and net cash provided by operating activities, and Free Cash Flow to net cash provided by operating activities, are included in the "Results of Operations" section below.

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Results of Operations

Segment Data

The table below and descriptions that follow represent the consolidated results of operations of the Company for the years ended December 31, 2024, 2023 and 2022.

Net External Sales

The table below presents net external sales on a disaggregated basis for our two principal operating segments. Performance Materials net external sales primarily consist of sales of PVC, polyethylene and epoxy. Essential Materials net external sales primarily consist of sales of caustic soda, chlorine, styrene, and related derivative materials. Housing Products net external sales primarily consist of sales of housing exterior and interior products, residential pipes and fittings and residential products utilizing PVC compounds. Infrastructure Products net external sales primarily consist of sales of infrastructure related pipes and fittings and infrastructure products utilizing PVC compounds.

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(1)See above for discussions on non-GAAP financial measures. See "Reconciliation of EBITDA to Net Income, Income from Operations and Net Cash Provided by Operating Activities" below.

(2)See above for discussions on non-GAAP financial measures. See "Reconciliation of Free Cash Flow to Net Cash Provided by Operating Activities" below.

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Reconciliation of EBITDA to Net Income, Income from Operations and Net Cash Provided by Operating Activities

The following table presents the reconciliation of EBITDA to net income, income from operations and net cash provided by operating activities, the most directly comparable GAAP financial measures, for each of the periods indicated.

Reconciliation of Free Cash Flow to Net Cash Provided by Operating Activities

The following table presents the reconciliation of Free Cash Flow to net cash provided by operating activities, the most directly comparable GAAP financial measure, for each of the periods indicated.

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2024 Compared with 2023

Summary

For the year ended December 31, 2024, net income attributable to Westlake Corporation was $602 million, or $4.64 per diluted share, on net sales of $12,142 million. This represents an increase in net income attributable to Westlake Corporation of $123 million, or $0.94 per diluted share, compared to 2023 net income attributable to Westlake Corporation of $479 million, or $3.70 per diluted share, on net sales of $12,548 million. Income from operations was $875 million for the year ended December 31, 2024, as compared to $729 million for the year ended December 31, 2023, an increase of $146 million. Our income from operations and net income for the twelve months ended December 31, 2023 was negatively impacted by an impairment charge of $475 million that comprised of Westlake Epoxy goodwill and long-lived assets of our epoxy base resin business in the Netherlands in the fourth quarter of 2023, and a pre-tax litigation charge of approximately $150 million related to a final settlement to fully resolve lawsuits involving certain liability claims. The absence of such changes in the twelve months ended December 31, 2024 had a positive impact on our net income and income for operations. Excluding these impacts, our income and income from operations in the twelve months ended December 31, 2024 were lower, primarily due to lower sales prices for PVC resin, caustic soda, chlorine and pipe and fittings and the accrual of $75 million for expenses associated with mothballing of the Units in Pernis, Netherlands during 2024. The decreases in net income and income from operations in the twelve months ended December 31, 2024 were partially offset by higher PVC resin, polyethylene, caustic soda, chlorine, pipe and fittings and siding and trim sales volumes and lower natural gas and feedstock costs. Net income for the twelve months ended December 31, 2024 was favorably impacted by higher interest income and was negatively impacted by income tax expense of $45 million as a result of changes in Louisiana tax laws, as discussed above. Lower sales prices for most of our major products in the Performance and Essential Materials segment was primarily due to weaker global demand due to lower industrial and manufacturing activity. Lower sales prices for pipes and fittings in the Housing and Infrastructure Products segment was driven by the competitive commercial environment. Net sales decreased by $406 million to $12,142 million in 2024 from $12,548 million in 2023, primarily due to lower sales prices for PVC resin, epoxy resin, caustic soda, chlorine and pipe and fittings, partially offset by higher sales volumes for PVC resin, polyethylene, epoxy resin, caustic soda, chlorine, pipe and fittings and siding and trim.

Net Sales. Net sales decreased by $406 million, or 3%, to $12,142 million in 2024 from $12,548 million in 2023, primarily due to lower sales prices for most of our products across both segments. Average sales prices for 2024 decreased by 10% as compared to 2023 as a result of weaker demand for PVC resin, epoxy resin, caustic soda, chlorine and pipe and fittings. Sales volumes increased by 6% in 2024 as compared to 2023, due to increased sales volumes for PVC resin, polyethylene, epoxy resin, caustic soda, chlorine, pipe and fittings and siding and trim.

Gross Profit. Gross profit margin percentage was 16% in 2024 as compared to 18% in 2023. The decline in gross margin percentage for the year ended December 31, 2024 as compared to the year ended December 31, 2023 was primarily due to lower prices for most of our products across both segments, which was partially offset by lower natural gas and feedstock costs. The 2023 gross profit margin was impacted by the litigation charge of $150 million, as discussed above.

Selling, General and Administrative Expenses. Selling, general and administrative expenses increased by $9 million to $874 million in 2024 from $865 million in 2023. This increase was mainly due to higher professional consulting, selling and technology related expenses, which was partially offset by lower employee benefit costs.

Amortization of Intangibles. Amortization expense remained relatively consistent at $117 million in 2024 as compared to $122 million in 2023.

Impairment of Goodwill and Long-Lived Assets. The 2023 impairment of $475 million comprised of Westlake Epoxy goodwill impairment of $128 million and long-lived asset impairment of $347 million related to our base epoxy resin business in the Netherlands was recognized within the Performance and Infrastructure Materials segment. No similar impairment charge was recognized in 2024.

Restructuring, Transaction and Integration-related Costs. Restructuring, transaction and integration-related costs increased by $63 million to $91 million in 2024 from $28 million in 2023. The 2024 costs primarily related to mothballing of the Units and consisted of expenses for environmental remediation and other plant mothballing expenses of approximately $71 million and employee severance and separation expenses of approximately $4 million. The restructuring and integration costs in 2023 were primarily related to plant closures resulting from the Company's manufacturing footprint optimization efforts.

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Interest Expense. Interest expense decreased by $6 million to $159 million in 2024 from $165 million in 2023, primarily due to the redemption of 0.875% senior notes of $300 million and capitalization of interest on capital projects.

Other Income, Net. Other income, net of $222 million in 2024 was higher than other income, net of $136 million in 2023, substantially due to a higher average cash and cash equivalents balance and higher interest rates in 2024, as compared to 2023, resulting in higher interest income.

Income Taxes. The effective income tax rate was 31% in 2024, which was higher than the 25% effective income tax rate in 2023. The effective income tax rate in 2024 was higher as compared to 2023, primarily due to the revaluation of state deferred tax assets and deferred tax liabilities for the change in corporate state income tax and apportionment rates as a result of the Louisiana tax law change, as discussed earlier under Recent Developments.

Performance and Essential Materials Segment

Net Sales. Net sales for the Performance and Essential Materials segment decreased by $511 million, or 6%, to $7,825 million in 2024 from $8,336 million in 2023. Average sales prices for the Performance and Essential Materials segment decreased by 12% in 2024 as compared to 2023. Lower Performance Materials sales prices were primarily due to lower PVC resin and epoxy resin sales prices. Lower Essential Materials sales prices were primarily due to lower caustic soda and chlorine sales prices resulting from weak global industrial and manufacturing activity. Sales volumes for the Performance and Essential Materials segment increased by 5% in 2024 as compared to 2023, primarily due to higher PVC resin, polyethylene, epoxy resin, caustic soda and chlorine sales volumes.

Income from Operations. Income from operations for the Performance and Essential Materials segment increased by $70 million to $129 million in 2024 from $59 million in 2023. The results for the twelve months ended December 31, 2023 were negatively impacted by a non-cash impairment charge of $475 million related to Westlake Epoxy goodwill and long-lived assets of our epoxy base resin business in the Netherlands, and a litigation charge of approximately $150 million related to a final settlement to fully resolve lawsuits involving certain liability claims, both of which were recorded in the fourth quarter of 2023. Excluding the impact of these charges in 2023, the income from operations was lower for the twelve months ended December 31, 2024 as compared to the twelve months ended December 31, 2023, primarily due to lower sales prices for most of our major products in this segment, particularly PVC resin, caustic soda, chlorine and epoxy resin. These decreases were partially offset by higher sales volumes for PVC resin, polyethylene, caustic soda and chlorine and lower natural gas and feedstock costs. The 2024 results were also impacted by an unplanned outage at the LACC joint venture ethylene production plant during the third quarter of 2024, resulting in lower operating rates and higher maintenance costs.

Housing and Infrastructure Products Segment

Net Sales. Net sales for the Housing and Infrastructure Products segment increased by $105 million, or 2%, to $4,317 million in 2024 from $4,212 million in 2023. Housing Products net sales of $3,644 million increased by $150 million as compared to 2023. Infrastructure Products net sales of $673 million decreased by $45 million as compared to 2023. Sales volumes for the Housing and Infrastructure Products segment increased by 8% in 2024, as compared to 2023 primarily due to higher sales of pipe and fittings and siding and trim. Average sales prices for the Housing and Infrastructure Products segment decreased by 6% in 2024 as compared to 2023, primarily due to lower sales prices for most of our products in this segment, primarily resulting from the competitive commercial environment.

Income from Operations. Income from operations for the Housing and Infrastructure Products segment increased by $97 million to $807 million in 2024 from $710 million in 2023. The increase in income from operations was primarily due to higher sales volumes for pipe and fittings and siding and trim and lower raw material and energy costs. These increases were partially offset by lower sales prices for most of our products in this segment in the twelve months ended December 31, 2024 as compared to the twelve months ended December 31, 2023.

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2023 Compared with 2022

Summary

For the year ended December 31, 2023, net income attributable to Westlake Corporation was $479 million, or $3.70 per diluted share, on net sales of $12,548 million. This represents a decrease in net income attributable to Westlake Corporation of $1,768 million, or $13.64 per diluted share, compared to 2022 net income attributable to Westlake Corporation of $2,247 million, or $17.34 per diluted share, on net sales of $15,794 million. Income from operations was $729 million for the year ended December 31, 2023, as compared to $3,050 million for the year ended December 31, 2022, a decrease of $2,321 million. The decrease in net income and income from operations was primarily due to lower sales prices and volumes for most of our products across both segments as a result of weaker global demand, a non-cash impairment charge of $475 million that comprised of Westlake Epoxy goodwill and long-lived assets of our epoxy base resin business in the Netherlands in the fourth quarter of 2023, and a pre-tax litigation charge of approximately $150 million related to a final settlement to fully resolve lawsuits involving certain liability claims. The decreases in net income and income from operations in 2023 were partially offset by lower natural gas and feedstock costs and lower amortization of intangibles. Net sales decreased by $3,246 million to $12,548 million in 2023 from $15,794 million in 2022, primarily due to lower sales prices and volumes for most of our products across both segments.

Net Sales. Net sales decreased by $3,246 million, or 21%, to $12,548 million in 2023 from $15,794 million in 2022, primarily due to lower sales prices and volumes for most of our products. Average sales prices for 2023 decreased by 16% as compared to 2022, due to continuing weaker demand for most of our products across both segments. Sales volumes decreased by 5% in 2023 as compared to 2022, substantially due to weaker global demand for many of our products across both segments.

Gross Profit. Gross profit margin percentage was 18% in 2023 as compared to 26% in 2022. The decline in gross margin percentage for the year ended December 31, 2023 as compared to the year ended December 31, 2022 was primarily due to lower prices for most of our products and the litigation charge, as discussed above, partially offset lower natural gas and feedstock costs.

Selling, General and Administrative Expenses. Selling, general and administrative expenses increased by $30 million to $865 million in 2023 from $835 million in 2022. This increase was mainly due to higher compensation and professional consulting expenses and a full year of selling, general and administrative expenses in the current year for the epoxy business acquired in February 2022.

Amortization of Intangibles. Amortization expense decreased by $33 million to $122 million in 2023 from $155 million in 2022, primarily due to the end of useful lives of certain intangible assets within the Housing and Infrastructure Products segment during 2022.

Impairment of Goodwill and Long-Lived Assets. The impairment of $475 million comprised of Westlake Epoxy goodwill impairment of $128 million and long-lived asset impairment of $347 million related to our base epoxy resin business in the Netherlands, recognized within the Performance and Infrastructure Materials segment.

Restructuring, Transaction and Integration-related Costs. Restructuring, transaction and integration-related costs decreased by $5 million to $28 million in 2023 from $33 million in 2022. The costs in 2023 are restructuring and integration costs primarily related to plant closures resulting from the Company's manufacturing footprint optimization efforts. The 2022 expenses primarily related to the integration-related consulting fees and restructuring expenses related to the businesses acquired in previous years.

Interest Expense. Interest expense decreased by $12 million to $165 million in 2023 from $177 million in 2022, primarily due to the repayment of $269 million of debt during 2022.

Other Income, Net. Other income, net of $136 million in 2023 was higher than other income, net of $73 million in 2022, substantially due to higher interest income attributable to a higher average cash and cash equivalents balance and higher interest rates in the current period and insurance recoveries in 2023.

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Income Taxes. The effective income tax rate was 25% in 2023, which was higher than the 22% effective income tax rate in 2022. The effective income tax rate in 2023 was higher as compared to 2022, primarily because Westlake Epoxy's goodwill impairment was not deductible for tax purposes, and because of a valuation allowance that was recorded against Westlake Epoxy Netherlands' deferred tax assets including net operating loss carryforwards, mostly generated from the impairment of long-lived assets. Such increase in the effective income tax rate was partially offset by an increase in U.S. federal research and development credits available to the Company and a decrease in state and foreign taxes.

Performance and Essential Materials Segment

Net Sales. Net sales for the Performance and Essential Materials segment decreased by $2,672 million, or 24%, to $8,336 million in 2023 from $11,008 million in 2022, primarily resulting from lower global demand for most of our products across our businesses under this segment. Average sales prices for the Performance and Essential Materials segment decreased by 21% in 2023 as compared to 2022. Lower Performance Materials sales prices were primarily due to lower PVC resin, polyethylene and epoxy sales prices. Lower Essential Materials sales prices were due to lower caustic soda sales prices. Sales volumes for the Performance and Essential Materials segment decreased by 3% in 2023 as compared to 2022, primarily due to lower epoxy and caustic soda sales volumes.

Income from Operations. Income from operations for the Performance and Essential Materials segment decreased by $2,357 million to $59 million in 2023 from $2,416 million in 2022. This decrease in income from operations was primarily due to lower sales prices and volumes for most of our products, a non-cash impairment charge of $475 million related to Westlake Epoxy goodwill and long-lived assets of our epoxy base resin business in the Netherlands, and a litigation charge of approximately $150 million related to a final settlement to fully resolve lawsuits involving certain liability claims, both of which were recorded in the fourth quarter of 2023, and planned and unplanned outages. These decreases were partially offset by lower natural gas and feedstock costs.

Housing and Infrastructure Products Segment

Net Sales. Net sales for the Housing and Infrastructure Products segment decreased by $574 million, or 12%, to $4,212 million in 2023 from $4,786 million in 2022. Housing Products net sales of $3,494 million decreased by $370 million as compared to 2022 primarily due to lower demand for most of our products across our housing businesses due to the downturn in U.S. residential construction throughout 2023, partially offset by higher sales prices for some of our building products. Infrastructure Products net sales of $718 million decreased by $204 million as compared to 2022, due to a continuing lower demand for our products attributable to customers destocking from elevated inventory levels in the prior year. Average sales prices for the Housing and Infrastructure Products segment decreased slightly by 3% in 2023 as compared to 2022. Sales volumes for the Housing and Infrastructure Products segment decreased by 9% in 2023, as compared to 2022.

Income from Operations. Income from operations for the Housing and Infrastructure Products segment increased by $35 million to $710 million in 2023 from $675 million in 2022. The increase in income from operations was primarily due to lower raw material costs and higher sales prices for some of our building products, partially offset by lower sales prices for PVC compounds and pipe and fittings and volumes across most of our housing and infrastructure businesses.

Cash Flows

Operating Activities

Operating activities provided cash of $1,314 million in 2024 as compared to cash provided by operating activities of $2,336 million in 2023. The $1,022 million decrease in cash flow from operating activities was mainly due to unfavorable changes in working capital and lower prices for most of our products resulting in lower operating income. Changes in components of working capital, which we define for purposes of this cash flow discussion as accounts receivable, inventories, prepaid expenses and other current assets, less accounts payable and accrued and other liabilities, used cash of $278 million in 2024, as compared to $600 million of cash provided in 2023, an unfavorable change of $878 million. The unfavorable changes in 2024 were substantially driven by the higher inventory at the end of 2024, as compared to 2023 and cash outflows in 2024 related to the 2023 litigation accrual.

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Operating activities provided cash of $2,336 million in 2023 as compared to cash provided by operating activities of $3,395 million in 2022. The $1,059 million decrease in cash flows from operating activities was mainly due to lower prices and demand for most of our products, partially offset by favorable changes in working capital. Changes in components of working capital, which we define for purposes of this cash flow discussion as accounts receivable, inventories, prepaid expenses and other current assets, less accounts payable and accrued and other liabilities, provided cash of $600 million in 2023, as compared to $174 million of cash provided in 2022, a favorable change of $426 million. The favorable changes in 2023 were substantially due to lower inventory costs driven by lower feedstock and fuel costs, as compared to 2022.

Investing Activities

Net cash used for investing activities during 2024 was $1,001 million as compared to net cash used of $1,037 million in 2023. The decrease in investing activities during 2024 was primarily because of the lower capital expenditures in 2024 as compared to 2023. Capital expenditures were $1,008 million during 2024 as compared to $1,034 million during 2023. Capital expenditures in 2024 were primarily related to projects to increase production capacity or reduce costs, maintenance and safety projects and environmental projects at our various facilities.

Net cash used for investing activities during 2023 was $1,037 million as compared to net cash used of $2,479 million in 2022. The decrease in investing activities during 2023 was primarily because of the epoxy acquisition in February 2022 for $1,163 million. Capital expenditures were $1,034 million during 2023 as compared to $1,108 million during 2022. Capital expenditures in 2023 and 2022 were primarily related to projects to increase production capacity or reduce costs, maintenance and safety projects and environmental projects at our various facilities. The investing activities during 2022 were comprised primarily of the acquisition of Westlake Epoxy in February 2022 for $1,163 million, the purchase of an additional 3.2% interest in LACC for $89 million, aggregate contributions of $87 million to LACC, capital expenditures, and other asset acquisitions.

Financing Activities

Net cash used by financing activities during 2024 was $650 million as compared to net cash used by financing activities of $245 million in 2023. The increase in cash used for financing activities during 2024 as compared to 2023 was primarily due to the redemption of $300 million aggregate principal amount of the 0.875% Senior Notes due 2024. Other financing activities during 2024 were primarily related to the $264 million payment of cash dividends, the $49 million payment of cash distributions to noncontrolling interests, repurchases of shares of our common stock for an aggregate purchase price of $60 million and inflows of $13 million from the exercise of stock options.

Net cash used by financing activities during 2023 was $245 million as compared to net cash used of $587 million in 2022. The financing activities during 2023 were primarily related to the $221 million payment of cash dividends, the $54 million payment of cash distributions to noncontrolling interests, repurchases of shares of our common stock for an aggregate purchase price of $23 million and inflows of $44 million from the exercise of stock options. Financing activities during 2022 were primarily related to the redemption of $250 million aggregate principal amount of the 3.60% 2022 Senior Notes, the $169 million payment of cash dividends, the $60 million payment of cash distributions to noncontrolling interests and repurchases of our common stock for an aggregate purchase price of $101 million.

Liquidity and Capital Resources

Liquidity and Financing Arrangements

Our principal sources of liquidity are from cash and cash equivalents, cash from operations, short-term borrowings under the Credit Agreement and our long-term financing.

In November 2014, our Board of Directors authorized a $250 million stock repurchase program (the "2014 Program"). In November 2015, our Board of Directors approved the expansion of the 2014 Program by an additional $150 million. In August 2018, our Board of Directors approved the further expansion of the existing 2014 Program by an additional $150 million. In August 2022, our Board of Directors approved the further expansion of the existing 2014 Program by an additional $500 million. During the year ended December 31, 2024, 480,081 shares of our common stock were repurchased for an aggregate purchase price of $60 million under the 2014 Program. As of December 31, 2024, we had repurchased 9,202,631 shares of our common stock for an aggregate purchase price of approximately $634 million under the 2014 Program. Purchases under the 2014 Program may be made either through the open market or in privately negotiated transactions. Decisions regarding the amount and the timing of purchases under the 2014 Program will be influenced by our cash on hand, our cash flows from operations, general market conditions and other factors. The 2014 Program may be discontinued by our Board of Directors at any time.

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On October 4, 2018, Westlake Chemical Partners LP ("Westlake Partners") and Westlake Chemical Partners GP LLC, the general partner of Westlake Partners, entered into an Equity Distribution Agreement with UBS Securities LLC, Barclays Capital Inc., Citigroup Global Markets Inc., Deutsche Bank Securities Inc., RBC Capital Markets, LLC, Merrill Lynch, Pierce, Fenner & Smith Incorporated and Wells Fargo Securities, LLC to offer and sell Westlake Partners common units, from time to time, up to an aggregate offering amount of $50 million. This Equity Distribution Agreement was amended on February 28, 2020 to reference a new shelf registration and subsequent renewals thereof for utilization under this agreement. No common units have been issued under this program in 2024, 2023 or 2022.

We believe that our sources of liquidity as described above are adequate to fund our normal operations and ongoing capital expenditures and turnaround activities. We commenced the next planned maintenance turnaround at our Petro 1 ethylene facility in the first quarter of 2025. Funding of any potential large expansions such as our recent acquisitions or potential future acquisitions or the redemption of debt may likely necessitate, and therefore depend on our ability to obtain, additional financing in the future. We may not be able to access additional liquidity at favorable interest rates due to volatility of the commercial credit markets.

Cash and Cash Equivalents

As of December 31, 2024, our cash and cash equivalents totaled $2,919 million.

In addition to our cash and cash equivalents, our credit agreement is available to provide liquidity as needed, as described under "Debt" below.

Debt

As of December 31, 2024, the carrying value of our indebtedness totaled $4,562 million. See Note 10 to the consolidated financial statements appearing elsewhere in this Form 10-K for a discussion of our long-term indebtedness. Defined terms used in this section have the definitions assigned to such terms in Note 10 to the consolidated financial statements included in Item 8 of this Form 10-K.

Our ability to make payments on our indebtedness and to fund planned capital expenditures will depend on our ability to generate cash in the future, which is subject to general economic, financial, competitive, legislative, regulatory and other factors that are beyond our control. Based on our current level of operations and unless we were to undertake a new expansion or large acquisition, we believe our cash flows from operations, available cash and available borrowings under our credit agreement will be adequate to meet our normal operating needs for the foreseeable future.

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Our long-term debt consisted of the following as of December 31, 2024:

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(1)    At our option, we may redeem the notes at any time on or after the specified par call date at a redemption price equal to 100% of the principal amount of the notes being redeemed plus accrued and unpaid interest.

(2)    At our option, we may redeem the notes at any time prior to the specified par call date at a redemption price equal to the greater of (i) 100% of the principal amount of the notes being redeemed plus accrued and unpaid interest and (ii) the sum of the present values of the remaining scheduled payments on the notes being redeemed that would be due if the notes matured on the specified par call date (not including any portion of such payments of interest accrued as of the redemption date), discounted to the redemption date on an annual basis at the applicable comparable government bond rate plus 30 basis points plus accrued and unpaid interest.

(3)    At our option, we may redeem the notes at any time prior to the specified par call date at a redemption price equal to the greater of (i) 100% of the principal amount of the notes being redeemed plus accrued and unpaid interest and (ii) the sum of the present values of the remaining scheduled payments on the notes being redeemed that would be due if the notes matured on the specified par call date (excluding accrued and unpaid interest to the redemption date), discounted to the redemption date on a semi-annual basis at the treasury rate plus 20 to 40 basis points plus accrued and unpaid interest.

(4)    At our option, we may redeem the notes at any time prior to the specified par call date at a redemption price equal to the greater of (i) 100% of the principal amount of the notes being redeemed plus accrued and unpaid interest and (ii) the sum of the present values of the remaining scheduled payments on the notes being redeemed (excluding accrued and unpaid interest to the redemption date), discounted to the redemption date on a semi-annual basis at the treasury rate plus 35 to 45 basis points, plus accrued and unpaid interest.

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(5)    In the event of a redemption of certain bonds (the "GO Zone Bonds") issued by the Louisiana Local Government Environmental Facility and Development Authority (the "Authority") in 2017, we will redeem notes equal in principal amount to the GO Zone Bonds to be redeemed at a redemption price equal to the redemption price of the GO Zone Bonds to be redeemed, plus accrued interest to the redemption date. The GO Zone Bonds are subject to optional redemption by the Authority upon the direction of the Company at any time on or after November 1, 2027, for 100% of the principal amount plus accrued interest to the redemption date.

(6)    The waste disposal revenue bonds expire in December 2027 and are subject to redemption and mandatory tender for purchase prior to maturity under certain conditions. Interest on the waste disposal revenue bonds accrues at a rate determined by a remarketing agent and is payable quarterly. The interest rate on the waste disposal revenue bonds at December 31, 2024 was 3.35%.

(7)    The 2026 Term Loan has a 5-year maturity and includes a government rate subsidy. The interest rate on the 2026 Term Loan as of December 31, 2024 was 1.08%.

The holders of the 3.60% 2026 Senior Notes, the 1.625% 2029 Senior Notes, the 3.375% 2030 Senior Notes, the 3.50% 2032 tax-exempt GO Zone Refunding Senior Notes, the 2.875% 2041 Senior Notes, the 5.00% 2046 Senior Notes, the 4.375% 2047 Senior Notes, the 3.125% 2051 Senior Notes and the 3.375% 2061 Senior Notes may require us to repurchase the notes at a price equal to 101% of their principal amount, plus accrued and unpaid interest to, but not including, the date of repurchase, upon the occurrence of both a "change of control" and, within 60 days of such change of control, a "below investment grade rating event" (as such terms are defined in the respective indentures governing these notes).

The indenture governing the 3.60% 2026 Senior Notes, the 1.625% 2029 Senior Notes, the 3.375% 2030 Senior Notes, the 3.50% 2032 tax-exempt GO Zone Refunding Senior Notes, the 2.875% 2041 Senior Notes, the 5.00% 2046 Senior Notes, the 4.375% 2047 Senior Notes, the 3.125% 2051 Senior Notes, and the 3.375% 2061 Senior Notes contains customary events of default and covenants that, among other things and subject to certain exceptions, restrict us and certain of our subsidiaries' ability to (1) incur certain secured indebtedness, (2) engage in certain sale and leaseback transactions and (3) consolidate, merge or transfer all or substantially all of our assets.

As of December 31, 2024, we were in compliance with all of our long-term debt covenants.

Redemption of 0.875% senior notes due 2024

On August 15, 2024, the Company redeemed $300 million aggregate principal amount of its outstanding 0.875% senior notes due August 15, 2024 at a redemption price equal to 100% of the principal amount of the senior notes to be redeemed plus accrued and unpaid interest thereon.

Credit Agreement

On June 9, 2022, we entered into a new $1.5 billion revolving credit facility that is scheduled to mature on June 9, 2027 (the "Credit Agreement") and, in connection therewith, terminated our then existing revolving credit agreement. The Credit Agreement bears interest at either (a) Adjusted Term SOFR (as defined in the Credit Agreement) plus a margin ranging from 1.00% to 1.625% per annum or (b) Alternate Base Rate (as defined in the Credit Agreement) plus a margin ranging from 0.00% to 0.625% per annum, in each case depending on the credit rating of the Company. The Credit Agreement contains certain affirmative and negative covenants, including a quarterly total leverage ratio financial maintenance covenant. As of December 31, 2024, we were in compliance with the total leverage ratio financial maintenance covenant.

The Credit Agreement also contains certain events of default and, if and for so long as certain events of default have occurred and are continuing, any overdue amounts outstanding under the Credit Agreement will accrue interest at an increased rate, the lenders can terminate their commitments to lend thereunder and payments of any outstanding amounts thereunder could be accelerated by the lenders. None of our subsidiaries are required to guarantee our obligations under the Credit Agreement.

The Credit Agreement includes a $150 million sub-limit for letters of credit, and any outstanding letters of credit will be deducted from availability under the facility. The Credit Agreement also provides for a discretionary $50 million commitment for swingline loans to be provided on a same-day basis. We may also increase the size of the facility, in increments of at least $25 million, up to a maximum of $500 million, subject to certain conditions and if certain lenders agree to commit to such an increase.

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Westlake Chemical Partners LP Credit Arrangements

Our subsidiary, Westlake Chemical Finance Corporation, is the lender party to a $600 million revolving credit facility with Westlake Chemical Partners LP ("Westlake Partners") (the "MLP Revolver") that is scheduled to mature on July 12, 2027. As of December 31, 2024, outstanding borrowings under the credit facility totaled $377 million and bore interest at Secured Overnight Financing Rate, as administered by the Federal Reserve Bank of New York ("SOFR") plus the Applicable Margin plus a 0.10% credit spread adjustment. On July 12, 2022, Westlake Partners entered into the Fourth Amendment (the "MLP Revolver Amendment") to the MLP Revolver. The MLP Revolver Amendment, among other things, extended the maturity date to July 12, 2027 and provided for the replacement of LIBOR with SOFR. Borrowings under the MLP Revolver now bear interest at a variable rate of either (a) SOFR plus the Applicable Margin plus a 0.10% credit spread adjustment or, if SOFR is no longer available, (b) the Alternate Base Rate plus the Applicable Margin minus 1.0%. The Applicable Margin under the MLP Revolver varies between 1.75% and 2.75%, depending on the Partnership's Consolidated Leverage Ratio.

Our subsidiary, Westlake Polymers LLC, is the administrative agent to a $600 million revolving credit facility with Westlake Chemical OpCo LP ("OpCo") (the "OpCo Revolver") that is scheduled to mature on July 12, 2027. As of December 31, 2024, outstanding borrowings under the credit facility totaled $23 million and bore interest at SOFR plus the Applicable Margin of 1.75% plus a 0.10% credit spread adjustment. On July 12, 2022, OpCo entered into the Second Amendment (the "OpCo Revolver Amendment") to the OpCo Revolver. The OpCo Revolver Amendment, among other things, extended the maturity date to July 12, 2027 and provided for the replacement of LIBOR with SOFR. Borrowings under the OpCo Revolver now bear interest at a variable rate of either (a) SOFR plus the Applicable Margin plus a 0.10% credit spread adjustment or, if SOFR is no longer available, (b) the Alternate Base Rate plus the Applicable Margin minus 1.0%. The Applicable Margin under the OpCo Revolver is 1.75%.

We consolidate Westlake Partners and OpCo for financial reporting purposes as we have a controlling financial interest. As such, the revolving credit facilities described above between our subsidiaries and Westlake Partners and OpCo are eliminated from the financial statements upon consolidation.

Contractual and Other Obligations

The Company's material cash requirements for contractual and other obligations in the near term (next 12 months) and the long term period (2026 and thereafter) include long-term debt, interest payments, operating leases, pension benefits funding, post-retirement healthcare benefits, purchase obligations, asset retirement obligations and letters of credit.

Debt Obligations and Interest Payments. As of December 31, 2024, we had $6 million debt obligations due within the near term, and debt obligations of $4,639 million due over the long-term period. At December 31, 2024, long-term debt related interest expense of $156 million was due within the near term, and related interest expense of $2,543 million was due over the long-term period. Maturities of our debt consist of $6 million in 2025, $751 million in 2026, $11 million in 2027 and $727 million in 2029. There are no other scheduled maturities of debt in 2025 through 2029. See Note 10, "Long-Term Debt," in the Notes to Consolidated Financial Statements in Item 8 of this Form 10-K for further information on our debt obligations and the expected timing of future principal and interest payments.

Operating Leases. As of December 31, 2024, there was $158 million in operating lease obligations due within the near term, and $881 million due over the long-term period. See Note 6, "Leases," in the Notes to Consolidated Financial Statements in Item 8 of this Form 10-K for further detail of our obligations and the timing of expected future payments.

Pension Benefits Funding and Post-retirement Healthcare Benefits. Pension benefits funding obligations due within the near term were $10 million while post-retirement healthcare benefit payment obligations due within the near term were $7 million as of December 31, 2024. As of December 31, 2024, we had $125 million and $49 million of pension benefit funding and post-retirement healthcare benefit obligations due over the long-term period, respectively. The estimate of the timing of future payments under our defined benefit pension plans which cover certain eligible employees in the United States and non-U.S. countries and our post-retirement healthcare benefits to the employees of certain subsidiaries who meet certain minimum age and service requirements involves the use of certain assumptions, including retirement ages and payout periods. See Note 13, "Employee Benefits," in the Notes to Consolidated Financial Statements in Item 8 of this Form 10-K for further information on our obligations and the timing of expected future payments.

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Purchase Obligations. Purchase obligations include agreements to purchase goods and services that are enforceable and legally binding and that specify all significant terms, including a minimum quantity and price. We are party to various obligations to purchase goods and services, including commitments to purchase various feedstock, utilities, nitrogen, oxygen, product storage, pipeline usage and logistic support, in each case in the ordinary course of our business, as well as various purchase commitments for our capital projects. As of December 31, 2024, we had $2,592 million of enforceable and legally binding purchase commitments due within the near term, and $5,509 million due over the long-term period.

Asset Retirement Obligations. As of December 31, 2024, we had $38 million asset retirement obligations due within the near term, and $34 million due over the long-term period. Asset retirement obligations includes the estimated costs and timing of payments to satisfy our recognized asset retirement obligations. We recognize asset retirement obligations in the period in which the liability becomes probable and reasonably estimable. Initially, the asset retirement obligation is recorded at fair value and capitalized as a component of the carrying value of the long-lived asset to which the obligation relates. See Note 1, "Description of Business and Significant Accounting Policies," in the Notes to Consolidated Financial Statements in Item 8 of this Form 10-K for further detail of our asset retirement obligations.

Letters of Credit. As of December 31, 2024, we had $45 million standby letters of credit, made in the ordinary course of business, maturing within the near term, and no standby letters of credit maturing over the long-term period. We had no letters of credit outstanding under our Credit Agreement.

Critical Accounting Policies and Estimates

Critical accounting policies are those that are important to our financial condition and require management's most difficult, subjective or complex judgments. Different amounts would be reported under different operating conditions or under alternative assumptions. We have evaluated the accounting policies used in the preparation of the accompanying consolidated financial statements and related notes and believe those policies are reasonable and appropriate. Our significant accounting policies are summarized in Note 1 to the consolidated financial statements appearing elsewhere in this Form 10-K.

Critical accounting estimates are those estimates made in accordance with the accounting principles generally accepted in the United States ("GAAP") that involve a significant level of estimation uncertainty and have had or are reasonably likely to have a material impact on our financial condition or results of operation. Our more critical accounting estimates include those related to business combinations, fair values, long-lived assets, goodwill, accruals for long-term employee benefits, accounts receivable, income taxes and environmental and legal obligations. Inherent in such estimates are certain key assumptions. We periodically update the estimates used in the preparation of the financial statements based on our latest assessment of the current and projected business and general economic environment. We believe the following to be our most critical accounting estimates required for the preparation of our financial statements.

Business Combinations and Intangible Assets Including Goodwill. We account for business combinations using the acquisition method of accounting, and accordingly, the assets and liabilities of the acquired business are recorded at their fair values at the date of acquisition. The excess of the purchase price over the estimated fair value is recorded as goodwill. Any changes in the estimated fair values of the net assets recorded for acquisitions prior to the finalization of more detailed analysis, but not to exceed one year from the date of acquisition, will change the amount of the purchase price allocable to goodwill. Any subsequent changes to any purchase price allocations that are material to our consolidated financial results will be adjusted in the same period's financial statements, including the effect on earnings of changes in depreciation, amortization or other income effects, if any, as a result of the change to the provisional amounts, calculated as if the accounting had been completed at the acquisition date. All acquisition costs are expensed as incurred and in-process research and development costs are recorded at fair value as an indefinite-lived intangible asset and assessed for impairment thereafter until completion, at which point the asset is amortized over its expected useful life. Separately recognized transactions associated with business combinations are generally expensed subsequent to the acquisition date. The application of business combination accounting requires the use of significant estimates and assumptions. Our estimates of fair value are based upon assumptions we believe to be reasonable, but which are inherently uncertain and unpredictable. The fair value of the customer relationships acquired are estimated by management through a discounted cash flow model using the multi-period excess earnings methodology, which involves the use of significant estimates and assumptions related to revenue growth rates, operating margins, discount rates, and customer attrition rates, among other items. The fair value of the technology and trade names acquired is estimated by management through a discounted cash flow model using the relief from royalty methodology, which involves the use of significant estimates and assumptions related to revenue growth rates, and discount rates. The results of operations of acquired businesses are included in our consolidated financial statements from the acquisition date.

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Fair Value Estimates. We develop estimates of fair value to allocate the purchase price paid to acquire a business to the assets acquired and liabilities assumed in an acquisition, to assess impairment of long-lived assets and goodwill and to record marketable securities and pension plan assets. We use all available information to make these fair value determinations, including the engagement of third-party consultants. In addition, we record all pension plan assets and certain marketable securities at fair value. The fair value of these items is determined by quoted market prices or from observable market-based inputs. See Note 15 to the consolidated financial statements appearing elsewhere in this Form 10-K for more information.

Long-Lived Assets. Key estimates related to long-lived assets include useful lives, recoverability of carrying values and existence of any retirement obligations. Such estimates could be significantly modified. The carrying values of long-lived assets could be impaired by significant changes or projected changes in supply and demand fundamentals (which could have a negative impact on operating rates or margins), new technological developments, new competitors with significant raw material or other cost advantages, adverse changes associated with the United States and global economies, the cyclical nature of the chemical and refining industries and uncertainties associated with governmental actions.

We evaluate long-lived assets for potential impairment indicators whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable, including when negative conditions such as significant current or projected operating losses exist. Our judgments regarding the existence of impairment indicators are based on legal factors, market conditions and the operational performance of our businesses. Actual impairment losses incurred could vary significantly from amounts estimated. Long-lived assets are assessed for impairment by asset group, the lowest level for which identifiable cash flows are largely independent of the cash flows of other groups of assets and liabilities. Additionally, future events could cause us to conclude that impairment indicators exist and that associated long-lived assets of our businesses are impaired. Any resulting impairment loss could have a material adverse impact on our financial condition and results of operations.

During the fourth quarter of 2023, the Westlake Epoxy business's sales volumes and prices, specifically base epoxy resins in Europe, continued to deteriorate. These lower sales volumes and prices were primarily driven by record exports out of Asia into Europe and North America. In addition, Westlake Epoxy operations in Europe have experienced sustained high energy and power costs. These factors negatively impacted Westlake Epoxy financial results during 2023. The Company identified these developments, along with management's outlook for the Westlake Epoxy business over the foreseeable future, as impairment indicators during the fourth quarter of 2023. Recoverability tests were performed for each of Westlake Epoxy's asset groups to compare the carrying amounts of assets to the net undiscounted cash flow projections of the asset group generated from its use and eventual disposition. The undiscounted cash flow projections were based on historical results, estimates made by management of future market conditions, current and future strategic and operational plans and future financial performance projected through the remaining useful life of the primary asset in the asset group. Based on the recoverability tests, we determined that the carrying amount of the primary assets of Westlake Epoxy's Netherlands asset group is not recoverable, and as such, an impairment loss was recorded in fourth quarter of 2023 to reduce the carrying amount of the asset group to its fair value. See Note 5 in the notes to the consolidated financial statements for further details.

The estimated useful lives of long-lived assets range from one to 40 years. Depreciation and amortization of these assets, including amortization of deferred turnaround costs, under the straight-line method over their estimated useful lives totaled $1,114 million, $1,097 million and $1,056 million in 2024, 2023 and 2022, respectively. If the useful lives of the assets were found to be shorter than originally estimated, depreciation or amortization charges would be accelerated.

We defer the costs of planned major maintenance activities, or turnarounds, and amortize the costs over the period until the next planned turnaround of the affected unit. Total costs deferred on turnarounds were $114 million, $179 million and $178 million in 2024, 2023 and 2022, respectively. As of December 31, 2024, deferred turnaround costs, net of accumulated amortization, totaled $352 million. Amortization in 2024, 2023 and 2022 of deferred turnaround costs was $153 million, $137 million and $80 million, respectively. Expensing turnaround costs as incurred would likely result in greater variability of our quarterly operating results and would adversely affect our financial position and results of operations. We commenced the next planned maintenance turnaround at our Petro 1 ethylene facility in the first quarter of 2025.

Additional information concerning long-lived assets and related depreciation and amortization appears in Notes 5 and 7 to the consolidated financial statements appearing elsewhere in this Form 10-K.

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Goodwill. At December 31, 2024, our recorded goodwill was $2,031 million. Goodwill is evaluated for impairment when events or changes in circumstances indicate the fair value of a reporting unit with goodwill has been reduced below its carrying amount, and otherwise at least annually. We perform our annual impairment assessment for both the Performance and Essential Materials and Housing and Infrastructure Products reporting units in the fourth quarter each year. We may elect to perform an optional qualitative assessment to determine whether a quantitative impairment analysis is required. The qualitative assessment considers factors such as macroeconomic conditions, industry and market considerations, cost factors related to raw materials and labor, current and projected financial performance, changes in management or strategy, and market capitalization. Alternatively, we may unconditionally elect to bypass the qualitative assessment and perform a quantitative goodwill impairment assessment in any period.

We performed the quantitative assessment for each of our reporting units within both of our segments during the fourth quarter of 2024. The quantitative analysis compares a reporting unit's fair value to its carrying amount to determine whether goodwill is impaired. The fair values of the reporting units are calculated using both a discounted cash flow methodology and a market value methodology. The discounted cash flow projections are based on a forecast to reflect the cyclicality of the business. The forecast is based on historical results, estimates by management of future market conditions, current and future strategic and operational plans and future financial performance. Significant assumptions used in the discounted cash flow projection include projected sales volumes based on production capacities, future sales prices, EBITDA margin, inclusive of feedstock, energy and power costs and capital expenditures. The future cash flows are discounted to present value using an applicable discount rate. The significant assumptions used in determining the fair value of the reporting unit using the market value methodology include the determination of appropriate market comparables and the estimated multiples of EBITDA a willing buyer is likely to pay. Based on the quantitative tests performed during the fourth quarter of 2024, the fair value of each of the reporting units with goodwill were substantially in excess of the carrying amounts. See Note 7 in the notes to the consolidated financial statements for further details. For all reporting units with goodwill, even if the fair values of the reporting units decreased by 10% from the fair values determined for the quantitative tests, the carrying amounts of the reporting units would not have exceeded their fair values. See Item 1A, "Risk Factors—If our goodwill or other long-lived assets become impaired in the future, we may be required to record non-cash charges to earnings, which could be significant."

Long-Term Employee Benefit Costs. Our costs for long-term employee benefits, particularly pension and postretirement medical and life benefits, are incurred over long periods of time and involve many uncertainties over those periods. The net periodic benefit cost attributable to current periods is based on several assumptions about such future uncertainties and is sensitive to changes in those assumptions. It is our responsibility, often with the assistance of independent experts, to select assumptions that represent the best estimates of those uncertainties. It is also our responsibility to review those assumptions periodically and, if necessary, adjust the assumptions to reflect changes in economic or other factors.

Accounting for employee retirement plans involves estimating the cost of benefits that are to be provided in the future and attempting to match, for each employee, that estimated cost to the period worked. To accomplish this, we rely extensively on advice from actuaries, and we make assumptions about inflation, investment returns, mortality, employee turnover and discount rates that ultimately impact amounts recorded. Changes in these assumptions may result in different expense and liability amounts. One of the more significant assumptions relates to the discount rate for measuring benefit obligations. At December 31, 2024, the projected pension benefit obligations for U.S. and non-U.S. plans were calculated using assumed weighted average discount rates of 5.5% and 3.5%, respectively. The discount rates were determined using a benchmark pension discount curve and applying spot rates from the curve to each year of expected benefit payments to determine the appropriate discount rate. As a result of the funding relief provided by the enactment of the Bipartisan Budget Act of 2015, no minimum funding requirements are expected during 2025 for the U.S. pension plans. Additional information on the 2025 funding requirements and key assumptions underlying these benefit costs appear in Note 13 to the consolidated financial statements appearing elsewhere in this Form 10-K.

The following table reflects the sensitivity of the benefit obligation of our pension plans to changes in the actuarial assumptions:

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A one-percentage point increase or decrease in assumed healthcare trend rates would not have a significant effect on the amounts reported for the healthcare plans.

While we believe that the amounts recorded in the consolidated financial statements appearing elsewhere in this Form 10-K related to these retirement plans are based on the best estimates and judgments available, the actual outcomes could differ from these estimates.

Income Taxes. We utilize the balance sheet method of accounting for deferred income taxes. Under this method, deferred tax assets or liabilities are recorded based upon temporary differences between the tax basis of assets and liabilities and their carrying values for financial reporting purposes. Deferred tax expense or benefit is the result of changes in the deferred tax assets and liabilities during the period. Valuation allowances are recorded against deferred tax assets when it is considered more likely than not that the deferred tax assets will not be realized. Additional information on income taxes appears in Note 16 to the consolidated financial statements appearing elsewhere in this Form 10-K.

Environmental and Legal Obligations. We consult with various professionals to assist us in making estimates relating to environmental costs and legal proceedings. We accrue an expense when we determine that it is probable that a liability has been incurred and the amount is reasonably estimable. While we believe that the amounts recorded in the accompanying consolidated financial statements related to these contingencies are based on the best estimates and judgments available, the actual outcomes could differ from our estimates. Additional information about certain legal proceedings and environmental matters appears in Note 21 to the consolidated financial statements appearing elsewhere in this Form 10-K.

Asset Retirement Obligations. We recognize asset retirement obligations in the period in which the liability becomes probable and reasonably estimable. Initially, the asset retirement obligation is recorded at fair value and capitalized as a component of the carrying value of the long-lived asset to which the obligation relates. The liability is recorded at its future value each period, and the capitalized cost is depreciated over the estimated useful life of the related asset. Upon settlement of the liability, a gain or loss is recorded. We have conditional asset retirement obligations for the removal and disposal of hazardous materials from certain of our manufacturing facilities. Additional information on asset retirement obligations appears in Note 1, under Asset Retirement Obligations, to the consolidated financial statements appearing elsewhere in this Form 10-K.

We also have conditional asset retirement obligations that have not been recognized because the fair values of the conditional legal obligations cannot be measured due to the indeterminate settlement date of the obligations. Settlements of the unrecognized conditional asset retirement obligations are not expected to have a material adverse effect on our financial condition, results of operations or cash flows in any individual reporting period.

Recent Accounting Pronouncements

See Note 1 to the consolidated financial statements included in Item 8 of this Form 10-K for a full description of recent accounting pronouncements, including expected date of adoption and estimated effect on results of operations and financial condition.

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Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations

Overview

We are a vertically integrated global manufacturer and marketer of performance and essential materials and housing and infrastructure products. We operate in two principal operating segments, Performance and Essential Materials and Housing and Infrastructure Products. The Performance and Essential Materials segment includes Westlake North American Vinyls, Westlake North American Chlor-alkali & Derivatives, Westlake European & Asian Chlorovinyls, Westlake Olefins, Westlake Polyethylene and Westlake Epoxy. The Housing and Infrastructure Products segment includes Westlake Royal Building Products, Westlake Pipe & Fittings, Westlake Global Compounds and Westlake Dimex. We are highly integrated along our materials chain with significant downstream integration from ethylene and chlor-alkali (chlorine and caustic soda) into vinyls, polyethylene, epoxy and styrene monomer. We also have substantial downstream integration from polyvinyl chloride ("PVC") into our building products, PVC pipes and fittings and PVC compounds in our Housing and Infrastructure Products segment.

During 2022 and continuing through the end of 2023, our European businesses have been impacted by higher energy prices, inflation and reduced demand. Our North American businesses, where we derive a significant portion of our revenue, have also experienced the impacts of high energy costs and interest rates and slower demand for most of our products since the second half of 2022. However, in recent months we have experienced lower energy costs as prices for electricity and natural gas have declined following the elevated 2022 levels and inflation appears to be easing. In the near term, we expect that the volatility in energy prices, higher interest rates, inflation and other macroeconomic conditions will continue to impact margins and demand for most of our products.

On February 1, 2022, we completed the acquisition of the global epoxy business of Hexion Inc. ("Westlake Epoxy") for total consideration of $1,207 million. The assets acquired and liabilities assumed and the results of operations of Westlake Epoxy are included in the Performance and Essential Materials segment. During the fourth quarter of 2023, the Westlake Epoxy business's sales volumes and prices, specifically base epoxy resins in Europe, continued to deteriorate. These lower sales volumes and prices have been primarily driven by record exports at lower prices of bisphenol-A, epichlorohydrin and base epoxy resins (constituting the epoxy value chain) out of Asia into Europe and North America during the time when demand in the European market was contracting. In addition, Westlake Epoxy operations in Europe have experienced sustained high energy and power costs. These factors negatively impacted Westlake Epoxy financial results during 2023. Based on these developments, along with management's outlook for the Westlake Epoxy business we determined, in the fourth quarter of 2023, that the carrying amount of long-lived assets of our base epoxy resin business in the Netherlands and all of the goodwill of the Westlake Epoxy business will not be recoverable in the foreseeable future. As a result of this assessment, a goodwill impairment charge of $128 million and a non-cash long-lived asset impairment charge of $347 million, related to our base epoxy resin business in the Netherlands, were recognized in the fourth quarter of 2023.

Performance and Essential Materials

Our performance and essential materials such as ethylene, PVC, polyethylene, epoxy and caustic soda are some of the most widely used materials in the world and are upgraded into a wide variety of higher value-added products used in many end-markets. Westlake is the second-largest chlor-alkali producer and the second-largest PVC producer in the world, which makes Westlake a leading global chlorovinyls producer. Our performance and essential materials are used by customers in food and specialty packaging; industrial and consumer packaging; medical health applications; PVC pipe applications; consumer durables; mobility and transportation; renewable wind energy; coatings; and housing and construction products. Chlor-alkali and petrochemicals are typically manufactured globally in large volume by a number of different producers using widely available technologies. The chlor-alkali and petrochemical industries exhibit cyclical commodity characteristics, and margins are influenced by changes in the balance between supply and demand and the resulting operating rates, the level of general economic activity and the price of raw materials. Due to the significant size of new plants, capacity additions are built in large increments and typically require several years of demand growth to be absorbed. The cycle is generally characterized by periods of tight supply, leading to high operating rates and margins, followed by a decline in operating rates and margins primarily as a result of excess new capacity additions. Westlake is one of the leading producers of epoxy specialty resins, modifiers and curing agents in Europe, the United States and Asia, with a global reach to our end markets. Epoxy resins are the fundamental component of many types of materials and are often used in the automotive, construction, wind energy, aerospace and electronics industries due to their superior adhesion, strength and durability. We are also a leading supplier of Liquid and Solid Epoxy Resin. These base epoxies are used in a wide variety of industrial coatings applications.

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Global demand for most of our products started to recover from the effects of the COVID-19 pandemic in the second half of 2020 and remained strong through the first half of 2022. However, since the second half of 2022 and continuing through the end of 2023, we saw significant volatility in natural gas and electricity prices, particularly in Europe, as well as in ethane and ethylene prices. We have also experienced lower prices and reduced demand for most of our products globally. The ongoing conflict between Russia and Ukraine since Russia's invasion of Ukraine in 2022, conflict in the Middle East, slow economic growth in China, increase in bisphenol-A, epichlorohydrin and base epoxy resin exports out of Asia into European and North American markets, timing of certain new ethylene and polyethylene capacity additions in North America, Asia, and the Middle East, volatility in natural gas and electricity prices, volatility in crude oil prices and inflationary pressures could have a continuing negative impact on the performance of Performance and Essential Materials businesses.

We purchase significant amounts of ethane feedstock, natural gas, ethylene and salt from external suppliers for use in production of performance and essential materials. We also purchase significant amounts of electricity to supply the energy required in our production processes. While we have agreements providing for the supply of ethane feedstock, natural gas, ethylene, salt and electricity, the contractual prices for these raw materials and energy vary with market conditions and may be highly volatile. Factors that have caused volatility in our raw material prices in the past, and which may do so in the future include:

•the availability of feedstock from shale gas and oil drilling;

•supply and demand for crude oil and natural gas;

•shortages of raw materials due to increasing demand;

•ethane and liquefied natural gas exports;

•capacity constraints due to higher construction costs for investments, construction delays, strike action or involuntary shutdowns;

•the general level of business and economic activity; and

•the direct or indirect effect of governmental regulation.

Significant volatility in raw material costs tends to put pressure on product margins as sales price increases could lag behind raw material cost increases. Conversely, when raw material costs decrease, customers may seek immediate relief in the form of lower sales prices. We currently use derivative instruments to reduce price volatility risk on feedstock commodities and lower overall costs. Normally, there is a pricing relationship between a commodity that we process and the feedstock from which it is derived. When this pricing relationship deviates from historical norms, we have from time to time entered into derivative instruments and physical positions in an attempt to take advantage of this relationship.

Our historical results have been significantly affected by our plant production capacity, our efficient use of that capacity and our ability to increase capacity. Since our inception, we have followed a disciplined growth strategy that focuses on plant acquisitions, new plant construction and internal expansion. We evaluate each expansion project on the basis of its ability to produce sustained returns in excess of our cost of capital and its ability to improve efficiency or reduce operating costs. We also regularly look at acquisition opportunities that would be consistent with, or complimentary to, our overall business strategies. Depending on the size of the acquisition, any such acquisitions could require external financing.

As noted above in Item 1A, "Risk Factors," we are subject to extensive environmental regulations, which may impose significant additional costs on our operations in the future. Further, concerns about greenhouse gas emissions and their possible effects on climate change has led to the enactment of regulations, and to proposed legislation and additional regulations, that could affect us in the form of increased cost of feedstocks and fuel, other increased costs of production and decreased demand for our products. While we do not expect any of these enactments or proposals to have a material adverse effect on us in the near term, we cannot predict the longer-term effect of any of these regulations or proposals on our future financial condition, results of operations or cash flows.

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Housing and Infrastructure Products

Our Housing and Infrastructure Products segment is primarily comprised of building products, PVC pipes and fittings and PVC compound products. Our sales are affected by the individual decisions of distributors and dealers on the levels of inventory they carry, their views on product demand, their financial condition and the manner in which they choose to manage inventory risk. A significant portion of our performance in this segment is driven by the activities in the residential construction and repair and remodeling markets in North America, which began to decline at the end of the second quarter of 2022 primarily due to the negative effect that rising mortgage rates in the United States had on buyer sentiment. Performance of our housing and infrastructure products businesses over time are generally reflective of the trends of building permits and housing starts in the New Residential Construction Survey by the U.S. Census Bureau and the Repair and Remodeling Index (RRI) provided by the National Association of Home Builders (the "NAHB") among others. Although we ultimately expect that the Infrastructure Investment and Jobs Act of 2021 and historically low residential housing construction may have a favorable long-term impact on certain industries related to our Housing and Infrastructure Products segment, the current inflationary environment impacting consumer spending and priorities, the possibility of recession or financial market instability, rapidly rising interest rates, decade high mortgage interest rates impacting consumer affordability, and ongoing labor and supply chain constraints are expected to have an unfavorable impact on the demand for housing construction in the near term and, as a result, our products produced by this segment. The lower demand for new housing construction as a result of the factors discussed above, however, could encourage homeowners to remodel and repair existing homes, which could have a favorable impact on our product sales

The following table presents annual historical housing starts per the U.S. Census Bureau and the 2024 and 2025 outlook per the NAHB:

North American PVC facilities within the Performance and Essential Materials segment supply most of the PVC required for our building products and PVC pipes and fittings plants. Our raw materials for stone, roofing and accessories, windows, shutters and specialty tool products are externally purchased. PVC required for the PVC compounds plants is either internally sourced from our North American and Asian facilities within the Performance and Essential Materials segment or externally purchased based on the location of the plants. The remaining feedstocks required, including pigments, fillers, stabilizers and other ingredients, are purchased under short-term contracts based on prevailing market prices.

Factors that have caused volatility in our raw material prices, energy costs and production processes in the past, and which may do so in the future, include significant fluctuation in prices of these raw materials in response to, among other things, variable worldwide supply and demand across different industries, speculation in commodities futures, general economic, business or environmental conditions, labor costs, competition, import duties, tariffs, worldwide currency fluctuations, freight, inflationary pressures, regulatory costs, and product and process evolutions that impact demand for the same materials. Increasing raw material prices directly impact our cost of sales and our ability to maintain margins depends on implementing price increases in response to increasing raw material costs. The market for our products may or may not accept price increases, and as such, our future financial condition, results of operations or cash flows could be materially impacted.

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Non-GAAP Financial Measures

The body of accounting principles generally accepted in the United States is commonly referred to as "GAAP." For this purpose, a non-GAAP financial measure is generally defined by the Securities and Exchange Commission ("SEC") as one that purports to measure historical or future financial performance, financial position or cash flows that (1) excludes amounts, or is subject to adjustments that have the effect of excluding amounts, that are included in the most directly comparable measure calculated and presented in accordance with GAAP in the statement of income, balance sheet or statement of cash flows (or equivalent statements) of the registrant; or (2) includes amounts, or is subject to adjustments that have the effect of including amounts, that are excluded from the most directly comparable measure so calculated and presented. In this report, we disclose non-GAAP financial measures, primarily earnings before interest, taxes, depreciation and amortization ("EBITDA") and Free Cash Flow. We define EBITDA as net income before interest expense, income taxes, depreciation and amortization. We define Free Cash Flow as net cash provided by operating activities less additions to property, plant and equipment. The non-GAAP financial measures described in this Form 10-K are not substitutes for the GAAP measures of earnings and cash flows.

EBITDA is included in this Form 10-K because our management considers it an important supplemental measure of our performance and believes that it is frequently used by securities analysts, investors and other interested parties in the evaluation of companies in our industry, some of which present EBITDA when reporting their results. We regularly evaluate our performance as compared to other companies in our industry that have different financing and capital structures and/or tax rates by using EBITDA. In addition, we utilize EBITDA in evaluating acquisition targets. Management also believes that EBITDA is a useful tool for measuring our ability to meet our future debt service and satisfy capital expenditure and working capital requirements, and EBITDA is commonly used by us and our investors to measure our ability to service indebtedness.

Free Cash Flow is included in this Form 10-K because our management considers it an important supplemental measure of our performance and believes that it is frequently used by securities analysts, investors and other interested parties in the evaluation of companies in our industry, some of which present Free Cash Flow when reporting their results. We regularly evaluate our performance as compared to other companies in our industry that have different financing and capital structures and/or tax rates by using Free Cash Flow. Management also believes that Free Cash Flow is useful to investors and securities analysts to evaluate our liquidity, evaluate strategic investment, evaluate our stock buyback plan and measure our ability to meet our future debt service.

EBITDA and Free Cash Flow are not substitutes for the GAAP measures of net income, income from operations and net cash provided by operating activities and are not necessarily measures of our ability to fund our cash needs. In addition, companies calculate EBITDA and Free Cash Flow differently and, therefore, EBITDA and Free Cash Flow as presented for us may not be comparable to EBITDA and Free Cash Flow reported by other companies. EBITDA has material limitations as a performance measure because it excludes interest expense, depreciation and amortization and income taxes. Free Cash Flow has material limitations as a performance measure because it only considers net cash provided by operating activities, and not net income or income from operations. For instance, it applies the entire cost of capital expenditure in the period in which the property or equipment is acquired, rather than spreading it over several periods as is the case with net income and income from operations.

Reconciliations of EBITDA to net income, income from operations and net cash provided by operating activities, and Free Cash Flow to net cash provided by operating activities, are included in the "Results of Operations" section below.

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Results of Operations

Segment Data

The table below and descriptions that follow represent the consolidated results of operations of the Company for the years ended December 31, 2023, 2022 and 2021.

Net External Sales

The table below presents net external sales on a disaggregated basis for our two principal operating segments. Performance Materials net external sales primarily consist of sales of PVC, polyethylene and epoxy. Essential Materials net external sales primarily consist of sales of caustic soda, styrene, and related derivative materials. Housing Products net external sales primarily consist of sales of housing exterior and interior products, residential pipes and fittings and residential PVC compounds. Infrastructure Products net external sales primarily consist of sales of non-residential pipes and fittings and non-residential PVC compounds.

______________________________

(1)See above for discussions on non-GAAP financial measures. See "Reconciliation of EBITDA to Net Income, Income from Operations and Net Cash Provided by Operating Activities" below.

(2)See above for discussions on non-GAAP financial measures. See "Reconciliation of Free Cash Flow to Net Cash Provided by Operating Activities" below.

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Reconciliation of EBITDA to Net Income, Income from Operations and Net Cash Provided by Operating Activities

The following table presents the reconciliation of EBITDA to net income, income from operations and net cash provided by operating activities, the most directly comparable GAAP financial measures, for each of the periods indicated.

Reconciliation of Free Cash Flow to Net Cash Provided by Operating Activities

The following table presents the reconciliation of Free Cash Flow to net cash provided by operating activities, the most directly comparable GAAP financial measure, for each of the periods indicated.

2023 Compared with 2022

Summary

For the year ended December 31, 2023, net income attributable to Westlake Corporation was $479 million, or $3.70 per diluted share, on net sales of $12,548 million. This represents a decrease in net income attributable to Westlake Corporation of $1,768 million, or $13.64 per diluted share, compared to 2022 net income attributable to Westlake Corporation of $2,247 million, or $17.34 per diluted share, on net sales of $15,794 million. Income from operations was $729 million for the year ended December 31, 2023, as compared to $3,050 million for the year ended December 31, 2022, a decrease of $2,321 million. The decrease in net income and income from operations was primarily due to lower sales prices and volumes for most of our products across both segments as a result of weaker global demand, a non-cash impairment charge of $475 million that comprised of Westlake Epoxy goodwill and long-lived assets of our epoxy base resin business in the Netherlands in the fourth quarter of 2023, and a pre-tax litigation charge of approximately $150 million related to a final settlement to fully resolve lawsuits involving certain liability claims. The decreases in net income and income from operations in 2023 were partially offset by lower natural gas and feedstock costs and lower amortization of intangibles. Net sales decreased by $3,246 million to $12,548 million in 2023 from $15,794 million in 2022, primarily due to lower sales prices and volumes for most of our products across both segments.

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Net Sales. Net sales decreased by $3,246 million, or 21%, to $12,548 million in 2023 from $15,794 million in 2022, primarily due to lower sales prices and volumes for most of our products. Average sales prices for 2023 decreased by 16% as compared to 2022, due to continuing weaker demand for most of our products across both segments. Sales volumes decreased by 5% in 2023 as compared to 2022, substantially due to weaker global demand for many of our products across both segments.

Gross Profit. Gross profit margin percentage was 18% in 2023 as compared to 26% in 2022. The decline in gross margin percentage for the year ended December 31, 2023 as compared to the year ended December 31, 2022 was primarily due to lower prices for most of our products and the litigation charge, as discussed above, partially offset lower natural gas and feedstock costs.

Selling, General and Administrative Expenses. Selling, general and administrative expenses increased by $30 million to $865 million in 2023 from $835 million in 2022. This increase was mainly due to higher compensation and professional consulting expenses and a full year of selling, general and administrative expenses in the current year for the epoxy business acquired in February 2022.

Amortization of Intangibles. Amortization expense decreased by $33 million to $122 million in 2023 from $155 million in 2022, primarily due to the end of useful lives of certain intangible assets within the Housing and Infrastructure Products segment during 2022.

Impairment of Goodwill and Long-Lived Assets. The impairment of $475 million comprised of Westlake Epoxy goodwill impairment of $128 million and long-lived asset impairment of $347 million related to our base epoxy resin business in the Netherlands, recognized within the Performance and Infrastructure Materials segment.

Restructuring, Transaction and Integration-related Costs. Restructuring, transaction and integration-related costs decreased by $5 million to $28 million in 2023 from $33 million in 2022. The costs in 2023 are restructuring and integration costs primarily related to plant closures resulting from the Company's manufacturing footprint optimization efforts. The 2022 expenses primarily related to the integration-related consulting fees and restructuring expenses related to the businesses acquired in previous years.

Interest Expense. Interest expense decreased by $12 million to $165 million in 2023 from $177 million in 2022, primarily due to the repayment of $269 million of debt during 2022.

Other Income, Net. Other income, net of $136 million in 2023 was higher than other income, net of $73 million in 2022, substantially due to higher interest income attributable to a higher average cash and cash equivalents balance and higher interest rates in the current period and insurance recoveries in 2023.

Income Taxes. The effective income tax rate was 25% in 2023, which was higher than the 22% effective income tax rate in 2022. The effective income tax rate in 2023 was higher as compared to 2022, primarily because Westlake Epoxy's goodwill impairment was not deductible for tax purposes, and because of a valuation allowance that was recorded against Westlake Epoxy Netherlands' deferred tax assets including net operating loss carryforwards, mostly generated from the impairment of long-lived assets. Such increase in the effective income tax rate was partially offset by an increase in U.S. federal research and development credits available to the Company and a decrease in state and foreign taxes.

Performance and Essential Materials Segment

Net Sales. Net sales for the Performance and Essential Materials segment decreased by $2,672 million, or 24%, to $8,336 million in 2023 from $11,008 million in 2022, primarily resulting from lower global demand for most of our products across our businesses under this segment. Average sales prices for the Performance and Essential Materials segment decreased by 21% in 2023 as compared to 2022. Lower Performance Materials sales prices were primarily due to lower PVC resin, polyethylene and epoxy sales prices. Lower Essential Materials sales prices were due to lower caustic soda sales prices. Sales volumes for the Performance and Essential Materials segment decreased by 3% in 2023 as compared to 2022, primarily due to lower epoxy and caustic soda sales volumes.

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Income from Operations. Income from operations for the Performance and Essential Materials segment decreased by $2,357 million to $59 million in 2023 from $2,416 million in 2022. This decrease in income from operations was primarily due to lower sales prices and volumes for most of our products, a non-cash impairment charge of $475 million related to Westlake Epoxy goodwill and long-lived assets of our epoxy base resin business in the Netherlands, and a litigation charge of approximately $150 million related to a final settlement to fully resolve lawsuits involving certain liability claims, both of which were recorded in the fourth quarter of 2023, and planned and unplanned outages. These decreases were partially offset by lower natural gas and feedstock costs.

Housing and Infrastructure Products Segment

Net Sales. Net sales for the Housing and Infrastructure Products segment decreased by $574 million, or 12%, to $4,212 million in 2023 from $4,786 million in 2022. Housing Products net sales of $3,494 million decreased by $370 million as compared to 2022 primarily due to lower demand for most of our products across our housing businesses due to the downturn in U.S. residential construction throughout 2023, partially offset by higher sales prices for some of our building products. Infrastructure Products net sales of $718 million decreased by $204 million as compared to 2022, due to a continuing lower demand for our products attributable to customers destocking from elevated inventory levels in the prior year. Average sales prices for the Housing and Infrastructure Products segment decreased slightly by 3% in 2023 as compared to 2022. Sales volumes for the Housing and Infrastructure Products segment decreased by 9% in 2023, as compared to 2022.

Income from Operations. Income from operations for the Housing and Infrastructure Products segment increased by $35 million to $710 million in 2023 from $675 million in 2022. The increase in income from operations was primarily due to lower raw material costs and higher sales prices for some of our building products, partially offset by lower sales prices for PVC compounds and pipe and fittings and volumes across most of our housing and infrastructure businesses.

2022 Compared with 2021

Summary

For the year ended December 31, 2022, net income attributable to Westlake Corporation was $2,247 million, or $17.34 per diluted share, on net sales of $15,794 million. This represents an increase in net income attributable to Westlake Corporation of $232 million, or $1.76 per diluted share, compared to 2021 net income attributable to Westlake Corporation of $2,015 million, or $15.58 per diluted share, on net sales of $11,778 million. Income from operations was $3,050 million for the year ended December 31, 2022, as compared to $2,800 million for the year ended December 31, 2021, an increase of $250 million. The increase in net income and income from operations was primarily due to significantly higher global sales prices for caustic soda and chlorine caused by higher demand through the year, and higher prices and margins on many of our products in the Housing and Infrastructure Products segment, due to strong demand for our products primarily during the first half of 2022. In addition, net income and income from operations included the contributions from the businesses acquired in the second half of 2021 and in the first quarter of 2022. Net income and income from operations for the year ended December 31, 2022 was negatively impacted by softening demand for PVC resin during the second half of 2022 due to slowing global economic conditions. In addition, higher natural gas, power and feedstock costs and a $70 million pre-tax litigation charge negatively impacted net income and income from operations during the year ended December 31, 2022. Selling, general and administrative expenses were also higher for the year ended December 31, 2022 primarily due to the businesses acquired in the second half of 2021 and in the first quarter of 2022. Net sales increased by $4,016 million to $15,794 million in 2022 from $11,778 million in 2021, due to higher sales prices for caustic soda and chlorine and for many of our products in the Housing and Infrastructure Products segment, partially offset by lower polyethylene sales prices. Sales volumes in the year ended December 31, 2022 were also higher in both segments as compared to the year ended December 31, 2021, primarily due to the contributions from the acquired businesses in the second half of 2021 and in the first quarter of 2022, partially offset by lower PVC resin, caustic soda and PVC compounds sales volumes.

Net Sales. Net sales increased by $4,016 million, or 34%, to $15,794 million in 2022 from $11,778 million in 2021, primarily due to higher sales prices for caustic soda and chlorine and for many of our products in the Housing and Infrastructure Products segment as well as higher sales volumes due to the businesses acquired in the second half of 2021 and in the first quarter of 2022, partially offset by lower polyethylene sales prices. Average sales prices for 2022 increased by 20% as compared to 2021 due to strong demand for caustic soda and strong residential construction, repair and remodeling markets in North America during the first half of 2022. Sales volumes increased by 14% in 2022 as compared to 2021, primarily due to the businesses acquired in the second half of 2021 and in the first quarter of 2022, partially offset by lower PVC resin, caustic soda and PVC compounds sales volumes.

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Gross Profit. Gross profit margin percentage was 26% in 2022 as compared to 30% in 2021. The decline in gross margin percentage for the year ended December 31, 2022 as compared to the year ended December 31, 2021 was primarily due to higher natural gas, power, feedstock and raw material costs and lower polyethylene sales prices. These decreases versus the prior year were partially offset by higher sales prices for caustic soda, chlorine, derivative products, pipes and fittings and PVC compounds.

Selling, General and Administrative Expenses. Selling, general and administrative expenses increased by $284 million to $835 million in 2022 from $551 million in 2021. This increase was mainly due to the inclusion of expenses related to the businesses acquired in the second half of 2021 and in the first quarter of 2022 as well as higher employee-related costs.

Amortization of Intangibles. Amortization expense increased by $32 million to $155 million in 2022 from $123 million in 2021, primarily due to the amortization of intangibles associated with the businesses acquired in the second half of 2021 and in the first quarter of 2022.

Restructuring, Transaction and Integration-related Costs. The restructuring, transaction and integration-related costs of $33 million and $21 million for the years ended December 31, 2022 and December 31, 2021, respectively, primarily consisted of restructuring, transaction and integration-related costs associated with the businesses acquired in the second half of 2021 and in the first quarter of 2022.

Interest Expense. Interest expense of $177 million in 2022 was comparable to $176 million in 2021. The full year interest expense in 2022 associated with the issuance of $1,700 million aggregate principal amount of senior notes in August 2021 was substantially offset by the realization of losses in 2021 on the settlement of interest rate lock arrangements associated with the senior notes issued in August 2021.

Other Income, Net. Other income, net of $73 million in 2022 was higher than other income, net of $53 million in 2021, primarily due to higher interest income.

Income Taxes. The effective income tax rate was 22% in 2022, which was slightly lower than the 23% effective tax rate in 2021. The effective tax rate in 2022 was lower as compared to 2021, primarily due to an increase in U.S. federal research and development credits available to the Company in 2022.

Performance and Essential Materials Segment

Net Sales. Net sales for the Performance and Essential Materials segment increased by $2,338 million, or 27%, to $11,008 million in 2022 from $8,670 million in 2021. Average sales prices for the Performance and Essential Materials segment increased by 15% in 2022 as compared to 2021. The increase in average sales prices were primarily driven by higher prices for caustic soda, chlorine and derivative products, partially offset by lower polyethylene sales prices. Sales volumes for the Performance and Essential Materials segment increased by 13% in 2022 as compared to 2021, primarily due to contributions from the recently acquired Westlake Epoxy business, which were partially offset by lower PVC resin, caustic soda and styrene sales volumes.

Income from Operations. Income from operations for the Performance and Essential Materials segment decreased by $133 million to $2,416 million in 2022 from $2,549 million in 2021. This decrease in income from operations was primarily due to lower polyethylene sales prices and integrated margins and lower sales volumes for PVC resin and caustic soda, higher natural gas, power and feedstock costs and a $70 million pre-tax litigation charge in the third quarter of 2022. The decrease in income from operations versus the prior-year was partially offset by higher sales prices for caustic soda, chlorine and derivative products and income from Westlake Epoxy, which was acquired in the first quarter of 2022. Trading activity in 2022 resulted in a loss of approximately $28 million as compared to a gain of $12 million in 2021.

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Housing and Infrastructure Products Segment

Net Sales. Net sales for the Housing and Infrastructure Products segment increased by $1,678 million, or 54%, to $4,786 million in 2022 from $3,108 million in 2021. Housing Products net sales of $3,864 million increased by $1,530 million as compared to 2021 primarily due to higher sales prices for all products as well as a full year of sales contribution from the businesses acquired in the second half of 2021. Infrastructure Products net sales of $922 million increased by $148 million as compared to 2021 primarily due to significantly higher sales prices. Average sales prices for the Housing and Infrastructure Products segment increased by 35% in 2022 as compared to 2021, primarily due to strong residential construction and repair and remodeling activity during the first half of 2022. Sales volumes for the Housing and Infrastructure Products segment increased by 19% in 2022, as compared to 2021, primarily due to contributions from the businesses acquired in the second half of 2021, partially offset by lower sales volumes for PVC compounds.

Income from Operations. Income from operations for the Housing and Infrastructure Products segment increased by $319 million to $675 million in 2022 from $356 million in 2021. The increase in income from operations was primarily due to higher sales prices driven by higher housing construction and remodeling activity during the first half of 2022. Income from operations was also higher due to contributions from the businesses acquired in the second half of 2021. The higher income from operations in 2022 as compared to 2021 was partially offset by higher raw material, power and production costs.

Cash Flows

Operating Activities

Operating activities provided cash of $2,336 million in 2023 as compared to cash provided by operating activities of $3,395 million in 2022. The $1,059 million decrease in cash flow from operating activities was mainly due to lower prices and demand for most of our products, partially offset by favorable changes in working capital. Changes in components of working capital, which we define for purposes of this cash flow discussion as accounts receivable, inventories, prepaid expenses and other current assets, less accounts payable and accrued and other liabilities, provided cash of $600 million in 2023, as compared to $174 million of cash provided in 2022, a favorable change of $426 million. The favorable changes in 2023 were substantially due to lower inventory costs driven by lower feedstock and fuel costs, as compared to 2022.

Operating activities provided cash of $3,395 million in 2022 as compared to cash provided by operating activities of $2,394 million in 2021. The $1,001 million increase in cash flows from operating activities was mainly due to the increase in income from operations, which was partially offset by working capital changes and an unfavorable change related to the turnaround at OpCo's Petro 2 facility and other turnaround activities. Changes in components of working capital, which we define for purposes of this cash flow discussion as accounts receivable, inventories, prepaid expenses and other current assets, less accounts payable and accrued and other liabilities, provided cash of $174 million in 2022, as compared to $383 million of cash used in 2021, a favorable change of $557 million. The majority of the unfavorable changes in 2021 were driven by higher accounts receivable and higher inventories, partially offset by higher accounts payable and accrued and other liabilities. The unfavorable change in accounts receivable was primarily driven by higher sales prices resulting in higher trade customer balances. The higher inventories, accounts payable and accrued and other liabilities in 2022 were primarily driven by higher inventory cost and an increase in operating activities, as compared to 2021.

Investing Activities

Net cash used for investing activities during 2023 was $1,037 million as compared to net cash used of $2,479 million in 2022. The decrease in investing activities during 2023 was primarily because of the epoxy acquisition in February 2022 for $1,163 million. Capital expenditures were $1,034 million during 2023 as compared to $1,108 million during 2022. Capital expenditures in 2023 and 2022 were primarily related to projects to increase production capacity or reduce costs, maintenance and safety projects and environmental projects at our various facilities. The investing activities during 2022 were comprised primarily of the acquisition of Westlake Epoxy in February 2022 for $1,163 million, the purchase of an additional 3.2% interest in LACC for $89 million, aggregate contributions of $87 million to LACC, capital expenditures, and other asset acquisitions.

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Net cash used for investing activities during 2022 was $2,479 million as compared to net cash used of $3,213 million in 2021. Investing activities during 2022 were comprised primarily of the acquisition of Westlake Epoxy in February 2022 for $1,163 million, the purchase of an additional 3.2% interest in LACC for $89 million, aggregate contributions of $87 million to LACC, capital expenditures, and other asset acquisitions. Our 2021 acquisition related activities were higher, as compared to 2022, due to the acquisitions of the Boral Target Companies, LASCO and Dimex for $2,554 million in the aggregate. Capital expenditures were $1,108 million in 2022 compared to $658 million in 2021. Capital expenditures in 2022 and 2021 were primarily related to expansion projects at various chlor-alkali plants as well as projects to improve production capacity or reduce costs, maintenance and safety projects and environmental projects at our various facilities.

Financing Activities

Net cash used by financing activities during 2023 was $245 million as compared to net cash used by financing activities of $587 million in 2022. The decrease in cash used for financing activities during 2023 as compared to 2022 was primarily due to the redemption of $250 million aggregate principal amount of the 3.60% Senior Notes due 2022 and higher repurchases of our common stock in 2022 as compared to 2023. The financing activities during 2023 were primarily related to the $221 million payment of cash dividends, the $54 million payment of cash distributions to noncontrolling interests, repurchases of shares of our common stock for an aggregate purchase price of $23 million and inflows of $44 million from the exercise of stock options. The financing activities during 2022 were primarily related to the redemption of $250 million aggregate principal amount of the 3.60% 2022 Senior Notes, $169 million payment of cash dividends, the $60 million payment of cash distributions to noncontrolling interests and repurchases of shares of our common stock for an aggregate purchase price of $101 million.

Net cash used by financing activities during 2022 was $587 million as compared to net cash provided of $1,437 million in 2021. Financing activities during 2022 were primarily related to the redemption of $250 million aggregate principal amount of the 3.60% 2022 Senior Notes, the $169 million payment of cash dividends, the $60 million payment of cash distributions to noncontrolling interests and repurchases of our common stock for an aggregate purchase price of $101 million. The activities during 2021 were primarily related to the registered public offering of $300 million aggregate principal amount of the 0.875% 2024 Senior Notes, $350 million aggregate principal amount of the 2.875% 2041 Senior Notes, $600 million aggregate principal amount of the 3.125% 2051 Senior Notes and $450 million aggregate principal amount of the 3.375% 2061 Senior Notes and the payment of debt issuance costs of $18 million related to such notes. The remaining activities in 2021 were primarily related to the $145 million payment of cash dividends, the $48 million payment of cash distributions to noncontrolling interests and repurchases of our common stock for an aggregate purchase price of $30 million.

Liquidity and Capital Resources

Liquidity and Financing Arrangements

Our principal sources of liquidity are from cash and cash equivalents, cash from operations, short-term borrowings under the Credit Agreement and our long-term financing.

In November 2014, our Board of Directors authorized a $250 million stock repurchase program (the "2014 Program"). In November 2015, our Board of Directors approved the expansion of the 2014 Program by an additional $150 million. In August 2018, our Board of Directors approved the further expansion of the existing 2014 Program by an additional $150 million. In August 2022, our Board of Directors approved the further expansion of the existing 2014 Program by an additional $500 million. As of December 31, 2023, we had repurchased 8,722,550 shares of our common stock for an aggregate purchase price of approximately $574 million under the 2014 Program. During the year ended December 31, 2023, 211,294 shares of our common stock were repurchased for an aggregate purchase price of $23 million under the 2014 Program. Purchases under the 2014 Program may be made either through the open market or in privately negotiated transactions. Decisions regarding the amount and the timing of purchases under the 2014 Program will be influenced by our cash on hand, our cash flows from operations, general market conditions and other factors. The 2014 Program may be discontinued by our Board of Directors at any time.

On October 4, 2018, Westlake Chemical Partners LP ("Westlake Partners") and Westlake Chemical Partners GP LLC, the general partner of Westlake Partners, entered into an Equity Distribution Agreement with UBS Securities LLC, Barclays Capital Inc., Citigroup Global Markets Inc., Deutsche Bank Securities Inc., RBC Capital Markets, LLC, Merrill Lynch, Pierce, Fenner & Smith Incorporated and Wells Fargo Securities, LLC to offer and sell Westlake Partners common units, from time to time, up to an aggregate offering amount of $50 million. This Equity Distribution Agreement was amended on February 28, 2020 to reference a new shelf registration and subsequent renewals thereof for utilization under this agreement. No common units were issued under this program in 2023, 2022 or 2021.

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We believe that our sources of liquidity as described above are adequate to fund our normal operations and ongoing capital expenditures and turnaround activities. Funding of any potential large expansions such as our recent acquisitions or potential future acquisitions or the redemption of debt may likely necessitate, and therefore depend on our ability to obtain, additional financing in the future. We may not be able to access additional liquidity at favorable interest rates due to volatility of the commercial credit markets.

Cash and Cash Equivalents

As of December 31, 2023, our cash and cash equivalents totaled $3,304 million.

In addition to our cash and cash equivalents, our credit agreement is available to provide liquidity as needed, as described under "Debt" below.

Debt

As of December 31, 2023, the carrying value of our indebtedness totaled $4,906 million. See Note 11 to the consolidated financial statements appearing elsewhere in this Form 10-K for a discussion of our long-term indebtedness. Defined terms used in this section have the definitions assigned to such terms in Note 11 to the consolidated financial statements included in Item 8 of this Form 10-K.

Our ability to make payments on our indebtedness and to fund planned capital expenditures will depend on our ability to generate cash in the future, which is subject to general economic, financial, competitive, legislative, regulatory and other factors that are beyond our control. Based on our current level of operations and unless we were to undertake a new expansion or large acquisition, we believe our cash flows from operations, available cash and available borrowings under our credit agreement will be adequate to meet our normal operating needs for the foreseeable future.

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Our long-term debt consisted of the following as of December 31, 2023:

______________________________

(1)    At our option, we may redeem the notes at any time on or after the specified par call date at a redemption price equal to 100% of the principal amount of the notes being redeemed plus accrued and unpaid interest.

(2)    At our option, we may redeem the notes at any time prior to the specified par call date at a redemption price equal to the greater of (i) 100% of the principal amount of the notes being redeemed plus accrued and unpaid interest and (ii) the sum of the present values of the remaining scheduled payments on the notes being redeemed that would be due if the notes matured on the specified par call date (not including any portion of such payments of interest accrued as of the redemption date), discounted to the redemption date on an annual basis at the applicable comparable government bond rate plus 30 basis points plus accrued and unpaid interest.

(3)    At our option, we may redeem the notes at any time prior to the specified par call date at a redemption price equal to the greater of (i) 100% of the principal amount of the notes being redeemed plus accrued and unpaid interest and (ii) the sum of the present values of the remaining scheduled payments on the notes being redeemed that would be due if the notes matured on the specified par call date (excluding accrued and unpaid interest to the redemption date), discounted to the redemption date on a semi-annual basis at the treasury rate plus 20 to 40 basis points plus accrued and unpaid interest.

(4)    At our option, we may redeem the notes at any time prior to the specified par call date at a redemption price equal to the greater of (i) 100% of the principal amount of the notes being redeemed plus accrued and unpaid interest and (ii) the sum of the present values of the remaining scheduled payments on the notes being redeemed (excluding accrued and unpaid interest to the redemption date), discounted to the redemption date on a semi-annual basis at the treasury rate plus 35 to 45 basis points, plus accrued and unpaid interest.

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(5)    In the event of a redemption of certain bonds (the "GO Zone Bonds") issued by the Louisiana Local Government Environmental Facility and Development Authority (the "Authority") in 2017, we will redeem notes equal in principal amount to the GO Zone Bonds to be redeemed at a redemption price equal to the redemption price of the GO Zone Bonds to be redeemed, plus accrued interest to the redemption date. The GO Zone Bonds are subject to optional redemption by the Authority upon the direction of the Company at any time on or after November 1, 2027, for 100% of the principal amount plus accrued interest to the redemption date.

(6)    The waste disposal revenue bonds expire in December 2027 and are subject to redemption and mandatory tender for purchase prior to maturity under certain conditions. Interest on the waste disposal revenue bonds accrues at a rate determined by a remarketing agent and is payable quarterly. The interest rate on the waste disposal revenue bonds at December 31, 2023 was 4.30%.

(7)    The 2026 Term Loan has a 5-year maturity and includes a government rate subsidy. The interest rate on the 2026 Term Loan as of December 31, 2023 was 0.95%.

The holders of the 0.875% 2024 Senior Notes, the 3.60% 2026 Senior Notes, the 1.625% 2029 Senior Notes, the 3.375% 2030 Senior Notes, the 3.50% 2032 tax-exempt GO Zone Refunding Senior Notes, the 2.875% 2041 Senior Notes, the 5.00% 2046 Senior Notes, the 4.375% 2047 Senior Notes, the 3.125% 2051 Senior Notes and the 3.375% 2061 Senior Notes may require us to repurchase the notes at a price equal to 101% of their principal amount, plus accrued and unpaid interest to, but not including, the date of repurchase, upon the occurrence of both a "change of control" and, within 60 days of such change of control, a "below investment grade rating event" (as such terms are defined in the respective indentures governing these notes).

The indenture governing the 0.875% 2024 Senior Notes, the 3.60% 2026 Senior Notes, the 1.625% 2029 Senior Notes, the 3.375% 2030 Senior Notes, the 3.50% 2032 tax-exempt GO Zone Refunding Senior Notes, the 2.875% 2041 Senior Notes, the 5.00% 2046 Senior Notes, the 4.375% 2047 Senior Notes, the 3.125% 2051 Senior Notes, and the 3.375% 2061 Senior Notes contains customary events of default and covenants that, among other things and subject to certain exceptions, restrict us and certain of our subsidiaries' ability to (1) incur certain secured indebtedness, (2) engage in certain sale and leaseback transactions and (3) consolidate, merge or transfer all or substantially all of our assets.

As of December 31, 2023, we were in compliance with all of our long-term debt covenants.

Credit Agreement

On June 9, 2022, we entered into a new $1.5 billion revolving credit facility that is scheduled to mature on June 9, 2027 (the "Credit Agreement") and, in connection therewith, terminated our then existing revolving credit agreement. The Credit Agreement bears interest at either (a) Adjusted Term SOFR (as defined in the Credit Agreement) plus a margin ranging from 1.00% to 1.625% per annum or (b) Alternate Base Rate (as defined in the Credit Agreement) plus a margin ranging from 0.00% to 0.625% per annum, in each case depending on the credit rating of the Company. The Credit Agreement contains certain affirmative and negative covenants, including a quarterly total leverage ratio financial maintenance covenant. As of December 31, 2023, we were in compliance with the total leverage ratio financial maintenance covenant.

The Credit Agreement also contains certain events of default and, if and for so long as certain events of default have occurred and are continuing, any overdue amounts outstanding under the Credit Agreement will accrue interest at an increased rate, the lenders can terminate their commitments to lend thereunder and payments of any outstanding amounts thereunder could be accelerated by the lenders. None of our subsidiaries are required to guarantee our obligations under the Credit Agreement.

The Credit Agreement includes a $150 million sub-limit for letters of credit, and any outstanding letters of credit will be deducted from availability under the facility. The Credit Agreement also provides for a discretionary $50 million commitment for swingline loans to be provided on a same-day basis. We may also increase the size of the facility, in increments of at least $25 million, up to a maximum of $500 million, subject to certain conditions and if certain lenders agree to commit to such an increase.

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Westlake Chemical Partners LP Credit Arrangements

Our subsidiary, Westlake Chemical Finance Corporation, is the lender party to a $600 million revolving credit facility with Westlake Chemical Partners LP ("Westlake Partners") (the "MLP Revolver") that is scheduled to mature on July 12, 2027. As of December 31, 2023, outstanding borrowings under the credit facility totaled $377 million and bore interest at Secured Overnight Financing Rate, as administered by the Federal Reserve Bank of New York ("SOFR") plus the Applicable Margin plus a 0.10% credit spread adjustment. On July 12, 2022, Westlake Partners entered into the Fourth Amendment (the "MLP Revolver Amendment") to the MLP Revolver. The MLP Revolver Amendment, among other things, extended the maturity date to July 12, 2027 and provided for the replacement of LIBOR with SOFR. Borrowings under the MLP Revolver now bear interest at a variable rate of either (a) SOFR plus the Applicable Margin plus a 0.10% credit spread adjustment or, if SOFR is no longer available, (b) the Alternate Base Rate plus the Applicable Margin minus 1.0%. The Applicable Margin under the MLP Revolver varies between 1.75% and 2.75%, depending on the Partnership's Consolidated Leverage Ratio.

Our subsidiary, Westlake Polymers LLC, is the administrative agent to a $600 million revolving credit facility with Westlake Chemical OpCo LP ("OpCo") (the "OpCo Revolver") that is scheduled to mature on July 12, 2027. As of December 31, 2023, outstanding borrowings under the credit facility totaled $23 million and bore interest at SOFR plus the Applicable Margin of 1.75% plus a 0.10% credit spread adjustment. On July 12, 2022, OpCo entered into the Second Amendment (the "OpCo Revolver Amendment") to the OpCo Revolver. The OpCo Revolver Amendment, among other things, extended the maturity date to July 12, 2027 and provided for the replacement of LIBOR with SOFR. Borrowings under the OpCo Revolver now bear interest at a variable rate of either (a) SOFR plus the Applicable Margin plus a 0.10% credit spread adjustment or, if SOFR is no longer available, (b) the Alternate Base Rate plus the Applicable Margin minus 1.0%. The Applicable Margin under the OpCo Revolver is 1.75%

We consolidate Westlake Partners and OpCo for financial reporting purposes as we have a controlling financial interest. As such, the revolving credit facilities described above between our subsidiaries and Westlake Partners and OpCo are eliminated from the financial statements upon consolidation.

Contractual and Other Obligations

The Company's material cash requirements for contractual and other obligations in the near term (next 12 months) and the long term period (2024 and thereafter) include long-term debt, interest payments, operating leases, pension benefits funding, post-retirement healthcare benefits, purchase obligations, asset retirement obligations and letters of credit.

Debt Obligations and Interest Payments. As of December 31, 2023, we had $300 million debt obligations due within the near term, and debt obligations of $4,697 million due over the long-term period. At December 31, 2023, long-term debt related interest expense of $158 million was due within the near term, and related interest expense of $2,692 million was due over the long-term period. Maturities of our debt consist of $300 million in 2024, $763 million in 2026 and $11 million in 2027. There are no other scheduled maturities of debt in 2024 through 2028. See Note 11, "Long-Term Debt," in the Notes to Consolidated Financial Statements in Item 8 of this Form 10-K for further information on our debt obligations and the expected timing of future principal and interest payments.

Operating leases. As of December 31, 2023, there was $142 million in operating lease obligations due within the near term, and $768 million due over the long-term period. See Note 7, "Leases," in the Notes to Consolidated Financial Statements in Item 8 of this Form 10-K for further detail of our obligations and the timing of expected future payments.

Pension Benefits Funding and Post-retirement Healthcare Benefits. Pension benefits funding obligations due within the near term were $8 million while post-retirement healthcare benefit payment obligations due within the near term were $8 million as of December 31, 2023. As of December 31, 2023, we had $135 million and $64 million of pension benefit funding and post-retirement healthcare benefit obligations due over the long-term period, respectively. The estimate of the timing of future payments under our defined benefit pension plans which cover certain eligible employees in the United States and non-U.S. countries and our post-retirement healthcare benefits to the employees of certain subsidiaries who meet certain minimum age and service requirements involves the use of certain assumptions, including retirement ages and payout periods. See Note 14, "Employee Benefits," in the Notes to Consolidated Financial Statements in Item 8 of this Form 10-K for further information on our obligations and the timing of expected future payments.

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Purchase Obligations. Purchase obligations include agreements to purchase goods and services that are enforceable and legally binding and that specify all significant terms, including a minimum quantity and price. We are party to various obligations to purchase goods and services, including commitments to purchase various feedstock, utilities, nitrogen, oxygen, product storage, pipeline usage and logistic support, in each case in the ordinary course of our business, as well as various purchase commitments for our capital projects. As of December 31, 2023, we had $2,152 million of enforceable and legally binding purchase commitments due within the near term, and $5,976 million due over the long-term period.

Asset Retirement Obligations. As of December 31, 2023, we had $3 million asset retirement obligations due within the near term, and $55 million due over the long-term period. Asset retirement obligations includes the estimated costs and timing of payments to satisfy our recognized asset retirement obligations. We recognize asset retirement obligations in the period in which the liability becomes probable and reasonably estimable. Initially, the asset retirement obligation is recorded at fair value and capitalized as a component of the carrying value of the long-lived asset to which the obligation relates. See Note 1, "Description of Business and Significant Accounting Policies," in the Notes to Consolidated Financial Statements in Item 8 of this Form 10-K for further detail of our asset retirement obligations.

Letters of Credit. As of December 31, 2023, we had $39 million standby letters of credit, made in the ordinary course of business, maturing within the near term, and no standby letters of credit maturing over the long-term period. We had no letters of credit outstanding under our Credit Agreement.

Critical Accounting Policies and Estimates

Critical accounting policies are those that are important to our financial condition and require management's most difficult, subjective or complex judgments. Different amounts would be reported under different operating conditions or under alternative assumptions. We have evaluated the accounting policies used in the preparation of the accompanying consolidated financial statements and related notes and believe those policies are reasonable and appropriate. Our significant accounting policies are summarized in Note 1 to the consolidated financial statements appearing elsewhere in this Form 10-K.

Critical accounting estimates are those estimates made in accordance with the accounting principles generally accepted in the United States ("GAAP") that involve a significant level of estimation uncertainty and have had or are reasonably likely to have a material impact on our financial condition or results of operation. Our more critical accounting estimates include those related to business combinations, fair values, long-lived assets, goodwill, accruals for long-term employee benefits, accounts receivable, income taxes and environmental and legal obligations. Inherent in such estimates are certain key assumptions. We periodically update the estimates used in the preparation of the financial statements based on our latest assessment of the current and projected business and general economic environment. We believe the following to be our most critical accounting estimates required for the preparation of our financial statements.

Business Combinations and Intangible Assets Including Goodwill. We account for business combinations using the acquisition method of accounting, and accordingly, the assets and liabilities of the acquired business are recorded at their fair values at the date of acquisition. The excess of the purchase price over the estimated fair value is recorded as goodwill. Any changes in the estimated fair values of the net assets recorded for acquisitions prior to the finalization of more detailed analysis, but not to exceed one year from the date of acquisition, will change the amount of the purchase price allocable to goodwill. Any subsequent changes to any purchase price allocations that are material to our consolidated financial results will be adjusted in the same period's financial statements, including the effect on earnings of changes in depreciation, amortization or other income effects, if any, as a result of the change to the provisional amounts, calculated as if the accounting had been completed at the acquisition date. All acquisition costs are expensed as incurred and in-process research and development costs are recorded at fair value as an indefinite-lived intangible asset and assessed for impairment thereafter until completion, at which point the asset is amortized over its expected useful life. Separately recognized transactions associated with business combinations are generally expensed subsequent to the acquisition date. The application of business combination accounting requires the use of significant estimates and assumptions. Our estimates of fair value are based upon assumptions we believe to be reasonable, but which are inherently uncertain and unpredictable. The fair value of the customer relationships acquired are estimated by management through a discounted cash flow model using the multi-period excess earnings methodology, which involves the use of significant estimates and assumptions related to revenue growth rates, operating margins, discount rates, and customer attrition rates, among other items. The fair value of the technology and trade names acquired is estimated by management through a discounted cash flow model using the relief from royalty methodology, which involves the use of significant estimates and assumptions related to revenue growth rates, and discount rates. The results of operations of acquired businesses are included in our consolidated financial statements from the acquisition date.

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Fair Value Estimates. We develop estimates of fair value to allocate the purchase price paid to acquire a business to the assets acquired and liabilities assumed in an acquisition, to assess impairment of long-lived assets and goodwill and to record marketable securities and pension plan assets. We use all available information to make these fair value determinations, including the engagement of third-party consultants. In addition, we record all pension plan assets and certain marketable securities at fair value. The fair value of these items is determined by quoted market prices or from observable market-based inputs. See Note 16 to the consolidated financial statements appearing elsewhere in this Form 10-K for more information.

Long-Lived Assets. Key estimates related to long-lived assets include useful lives, recoverability of carrying values and existence of any retirement obligations. Such estimates could be significantly modified. The carrying values of long-lived assets could be impaired by significant changes or projected changes in supply and demand fundamentals (which could have a negative impact on operating rates or margins), new technological developments, new competitors with significant raw material or other cost advantages, adverse changes associated with the United States and global economies, the cyclical nature of the chemical and refining industries and uncertainties associated with governmental actions.

We evaluate long-lived assets for potential impairment indicators whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable, including when negative conditions such as significant current or projected operating losses exist. Our judgments regarding the existence of impairment indicators are based on legal factors, market conditions and the operational performance of our businesses. Actual impairment losses incurred could vary significantly from amounts estimated. Long-lived assets are assessed for impairment by asset group, the lowest level for which identifiable cash flows are largely independent of the cash flows of other groups of assets and liabilities. Additionally, future events could cause us to conclude that impairment indicators exist and that associated long-lived assets of our businesses are impaired. Any resulting impairment loss could have a material adverse impact on our financial condition and results of operations.

During the fourth quarter of 2023, the Westlake Epoxy business's sales volumes and prices, specifically base epoxy resins in Europe, continued to deteriorate. These lower sales volumes and prices were primarily driven by record exports out of Asia into Europe and North America. In addition, Westlake Epoxy operations in Europe have experienced sustained high energy and power costs. These factors negatively impacted Westlake Epoxy financial results during 2023. The Company identified these developments, along with management's outlook for the Westlake Epoxy business over the foreseeable future, as impairment indicators during the fourth quarter of 2023. Recoverability tests were performed for each of Westlake Epoxy's asset groups to compare the carrying amounts of assets to the net undiscounted cash flow projections of the asset group generated from its use and eventual disposition. The undiscounted cash flow projections were based on historical results, estimates made by management of future market conditions, current and future strategic and operational plans and future financial performance projected through the remaining useful life of the primary asset in the asset group. Based on the recoverability tests, we determined that the carrying amount of the primary assets of Westlake Epoxy's Netherlands asset group is not recoverable, and as such, an impairment loss was recorded to reduce the carrying amount of the asset group to its fair value. See Note 6 in the notes to the consolidated financial statements for further details.

The estimated useful lives of long-lived assets range from one to 40 years. Depreciation and amortization of these assets, including amortization of deferred turnaround costs, under the straight-line method over their estimated useful lives totaled $1,097 million, $1,056 million and $840 million in 2023, 2022 and 2021, respectively. If the useful lives of the assets were found to be shorter than originally estimated, depreciation or amortization charges would be accelerated.

We defer the costs of planned major maintenance activities, or turnarounds, and amortize the costs over the period until the next planned turnaround of the affected unit. Total costs deferred on turnarounds were $179 million, $178 million and $215 million in 2023, 2022 and 2021, respectively. As of December 31, 2023, deferred turnaround costs, net of accumulated amortization, totaled $391 million. Amortization in 2023, 2022 and 2021 of deferred turnaround costs was $137 million, $80 million and $56 million, respectively. Expensing turnaround costs as incurred would likely result in greater variability of our quarterly operating results and would adversely affect our financial position and results of operations.

Additional information concerning long-lived assets and related depreciation and amortization appears in Notes 6 and 8 to the consolidated financial statements appearing elsewhere in this Form 10-K.

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Goodwill. At December 31, 2023, our recorded goodwill was $2,041 million. Goodwill is evaluated for impairment when events or changes in circumstances indicate the fair value of a reporting unit with goodwill has been reduced below its carrying value, and otherwise at least annually. We perform our annual impairment assessment for both the Performance and Essential Materials and Housing and Infrastructure Products reporting units in October each year. We may elect to perform an optional qualitative assessment to determine whether a quantitative impairment analysis is required. The qualitative assessment considers factors such as macroeconomic conditions, industry and market considerations, cost factors related to raw materials and labor, current and projected financial performance, changes in management or strategy, and market capitalization. Alternatively, we may unconditionally elect to bypass the qualitative assessment and perform a quantitative goodwill impairment assessment in any period.

We evaluated the Westlake Epoxy reporting unit's goodwill for impairment during the fourth quarter of 2023 in line with the timing of our annual goodwill impairment assessment for all reporting units. We performed the quantitative assessment for each of our reporting units within both of our segments during the fourth quarter of 2023. The quantitative analysis compares a reporting unit's fair value to its carrying amount to determine whether goodwill is impaired. The fair values of the reporting units are calculated using both a discounted cash flow methodology and a market value methodology. The discounted cash flow projections are based on a forecast to reflect the cyclicality of the business. The forecast is based on historical results, estimates by management of future market conditions, current and future strategic and operational plans and future financial performance. Significant assumptions used in the discounted cash flow projection included projected sales volumes based on production capacities, future sales prices, feedstock, energy and power costs and capital expenditures to maintain safe and reliable plant operations. The future cash flows are discounted to present value using an applicable discount rate. The significant assumptions used in determining the fair value of the reporting unit using the market value methodology include the determination of appropriate market comparables and the estimated multiples of EBITDA a willing buyer is likely to pay. Based on the quantitative tests performed during the fourth quarter of 2023, an impairment of the Westlake Epoxy reporting unit was identified as the carrying amount of the reporting unit exceeded its fair value. See Note 8 in the notes to the consolidated financial statements for further details. For all reporting units other than Westlake Epoxy, even if the fair values of the reporting units decreased by 10% from the fair values determined for the quantitative tests, the carrying amounts of the reporting units would not have exceeded their fair values. See Item 1A, "Risk Factors—If our goodwill or other long-lived assets become impaired in the future, we may be required to record non-cash charges to earnings, which could be significant."

Long-Term Employee Benefit Costs. Our costs for long-term employee benefits, particularly pension and postretirement medical and life benefits, are incurred over long periods of time and involve many uncertainties over those periods. The net periodic benefit cost attributable to current periods is based on several assumptions about such future uncertainties and is sensitive to changes in those assumptions. It is our responsibility, often with the assistance of independent experts, to select assumptions that represent the best estimates of those uncertainties. It is also our responsibility to review those assumptions periodically and, if necessary, adjust the assumptions to reflect changes in economic or other factors.

Accounting for employee retirement plans involves estimating the cost of benefits that are to be provided in the future and attempting to match, for each employee, that estimated cost to the period worked. To accomplish this, we rely extensively on advice from actuaries, and we make assumptions about inflation, investment returns, mortality, employee turnover and discount rates that ultimately impact amounts recorded. Changes in these assumptions may result in different expense and liability amounts. One of the more significant assumptions relates to the discount rate for measuring benefit obligations. At December 31, 2023, the projected pension benefit obligations for U.S. and non-U.S. plans were calculated using assumed weighted average discount rates of 5.0% and 3.2%, respectively. The discount rates were determined using a benchmark pension discount curve and applying spot rates from the curve to each year of expected benefit payments to determine the appropriate discount rate. As a result of the funding relief provided by the enactment of the Bipartisan Budget Act of 2015, no minimum funding requirements are expected during 2024 for the U.S. pension plans. Additional information on the 2024 funding requirements and key assumptions underlying these benefit costs appear in Note 14 to the consolidated financial statements appearing elsewhere in this Form 10-K.

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The following table reflects the sensitivity of the benefit obligation of our pension plans to changes in the actuarial assumptions:

A one-percentage point increase or decrease in assumed healthcare trend rates would not have a significant effect on the amounts reported for the healthcare plans.

While we believe that the amounts recorded in the consolidated financial statements appearing elsewhere in this Form 10-K related to these retirement plans are based on the best estimates and judgments available, the actual outcomes could differ from these estimates.

Income Taxes. We utilize the balance sheet method of accounting for deferred income taxes. Under this method, deferred tax assets or liabilities are recorded based upon temporary differences between the tax basis of assets and liabilities and their carrying values for financial reporting purposes. Deferred tax expense or benefit is the result of changes in the deferred tax assets and liabilities during the period. Valuation allowances are recorded against deferred tax assets when it is considered more likely than not that the deferred tax assets will not be realized. Additional information on income taxes appears in Note 17 to the consolidated financial statements appearing elsewhere in this Form 10-K.

Environmental and Legal Obligations. We consult with various professionals to assist us in making estimates relating to environmental costs and legal proceedings. We accrue an expense when we determine that it is probable that a liability has been incurred and the amount is reasonably estimable. While we believe that the amounts recorded in the accompanying consolidated financial statements related to these contingencies are based on the best estimates and judgments available, the actual outcomes could differ from our estimates. Additional information about certain legal proceedings and environmental matters appears in Note 22 to the consolidated financial statements appearing elsewhere in this Form 10-K.

Asset Retirement Obligations. We recognize asset retirement obligations in the period in which the liability becomes probable and reasonably estimable. Initially, the asset retirement obligation is recorded at fair value and capitalized as a component of the carrying value of the long-lived asset to which the obligation relates. The liability is recorded at its future value each period, and the capitalized cost is depreciated over the estimated useful life of the related asset. Upon settlement of the liability, a gain or loss is recorded. We have conditional asset retirement obligations for the removal and disposal of hazardous materials from certain of our manufacturing facilities. Additional information on asset retirement obligations appears in Note 1, under Asset Retirement Obligations, to the consolidated financial statements appearing elsewhere in this Form 10-K.

We also have conditional asset retirement obligations that have not been recognized because the fair values of the conditional legal obligations cannot be measured due to the indeterminate settlement date of the obligations. Settlements of the unrecognized conditional asset retirement obligations are not expected to have a material adverse effect on our financial condition, results of operations or cash flows in any individual reporting period.

Recent Accounting Pronouncements

See Note 1 to the consolidated financial statements included in Item 8 of this Form 10-K for a full description of recent accounting pronouncements, including expected date of adoption and estimated effect on results of operations and financial condition.

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Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations

Overview

We are a vertically integrated global manufacturer and marketer of performance and essential materials and housing and infrastructure products. We operate in two principal operating segments, Performance and Essential Materials and Housing and Infrastructure Products. The Performance and Essential Materials segment includes Westlake North American Vinyls, Westlake North American Chlor-alkali & Derivatives, Westlake European & Asian Chlorovinyls, Westlake Olefins, Westlake Polyethylene and Westlake Epoxy. The Housing and Infrastructure Products segment includes Westlake Royal Building Products, Westlake Pipe & Fittings, Westlake Global Compounds and Westlake Dimex. Prior to our segment reorganization in the fourth quarter of 2021, we operated in two principal operating segments, Vinyls and Olefins. The change has been retrospectively reflected in the periods presented in this Form 10-K. We are highly integrated along our materials chain with significant downstream integration from ethylene and chlor-alkali (chlorine and caustic soda) into vinyls, polyethylene, epoxy and styrene monomer. We also have substantial downstream integration from polyvinyl chloride ("PVC") into our building products, PVC pipes and fittings and PVC compounds in our Housing and Infrastructure Products segment.

During 2022, our European businesses continued to be impacted by higher energy prices, inflation and reduced demand. Our North American businesses, where we derive a significant portion of our revenue, also saw impacts of rising energy costs and interest rates and slowing demand. In the near term, we expect that higher energy costs, higher interest rates, inflation and other macroeconomic conditions could reduce margins and demand for most of our products.

Performance and Essential Materials

Our performance and essential materials such as ethylene, PVC, polyethylene, epoxy and chlor-alkali are some of the most widely used materials in the world and are upgraded into a wide variety of higher value-added products used in many end-markets. Westlake is the second-largest chlor-alkali producer and the second-largest PVC producer in the world, which makes Westlake a leading global chlorovinyls producer. Our performance and essential materials are used by customers in food and specialty packaging; industrial and consumer packaging; medical health applications; PVC pipe applications; consumer durables; mobility and transportation; renewable wind energy; coatings; and housing and construction products. Chlor-alkali and petrochemicals are typically manufactured globally in large volume by a number of different producers using widely available technologies. The chlor-alkali and petrochemical industries exhibit cyclical commodity characteristics, and margins are influenced by changes in the balance between supply and demand and the resulting operating rates, the level of general economic activity and the price of raw materials. Due to the significant size of new plants, capacity additions are built in large increments and typically require several years of demand growth to be absorbed. The cycle is generally characterized by periods of tight supply, leading to high operating rates and margins, followed by a decline in operating rates and margins primarily as a result of excess new capacity additions.

Demand for our products in the first half of 2020 was negatively impacted by the onset of the COVID-19 pandemic. Global demand for most of our products started strengthening in the second half of 2020 and remained strong through the first half of 2022. However, in the past year, we have seen significant volatility in natural gas, ethane and ethylene prices, primarily due to changes in demand, the timing for certain new ethylene capacity additions, the availability of natural gas liquids, and the ongoing conflict between Russia and Ukraine. Depending on the performance of the global economy, the timing of resolution of the conflict between Russia and Ukraine, disruption in the global supply chain, the extent to which we must rely on export markets, volatility in natural gas and electricity prices in Europe and across the world, labor shortages and costs, potential resurgence of the COVID-19 pandemic, the trend of crude oil prices, new ethylene and polyethylene capacity additions in North America, Asia and the Middle East in 2022 and beyond, the continued demand for most of our products in this segment, inflationary pressures and concerns over slower future economic growth, including the possibility of recession or financial market instability, our financial condition, results of operations or cash flows could be negatively or positively impacted.

We purchase significant amounts of ethane feedstock, natural gas, ethylene and salt from external suppliers for use in production of performance and essential materials. We also purchase significant amounts of electricity to supply the energy required in our production processes. While we have agreements providing for the supply of ethane feedstock, natural gas, ethylene, salt and electricity, the contractual prices for these raw materials and energy vary with market conditions and may be highly volatile. Factors that have caused volatility in our raw material prices in the past, and which may do so in the future include:

•the availability of feedstock from shale gas and oil drilling;

•supply and demand for crude oil and natural gas;

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•shortages of raw materials due to increasing demand;

•ethane and liquefied natural gas exports;

•capacity constraints due to higher construction costs for investments, construction delays, strike action or involuntary shutdowns;

•the general level of business and economic activity; and

•the direct or indirect effect of governmental regulation.

Significant volatility in raw material costs tends to put pressure on product margins as sales price increases could lag behind raw material cost increases. Conversely, when raw material costs decrease, customers may seek immediate relief in the form of lower sales prices. We currently use derivative instruments to reduce price volatility risk on feedstock commodities and lower overall costs. Normally, there is a pricing relationship between a commodity that we process and the feedstock from which it is derived. When this pricing relationship deviates from historical norms, we have from time to time entered into derivative instruments and physical positions in an attempt to take advantage of this relationship.

Our historical results have been significantly affected by our plant production capacity, our efficient use of that capacity and our ability to increase capacity. Since our inception, we have followed a disciplined growth strategy that focuses on plant acquisitions, new plant construction and internal expansion. We evaluate each expansion project on the basis of its ability to produce sustained returns in excess of our cost of capital and its ability to improve efficiency or reduce operating costs. We also regularly look at acquisition opportunities that would be consistent with, or complimentary to, our overall business strategies. Depending on the size of the acquisition, any such acquisitions could require external financing.

On February 1, 2022, we completed the acquisition of the Westlake Epoxy business for a purchase consideration of $1,207 million. The assets acquired and liabilities assumed and the results of operations of the Westlake Epoxy business are included in the Performance and Essential Materials segment. This acquisition represents a significant strategic expansion of Westlake's Performance and Essential Materials businesses into additional high-growth, innovative and sustainability-oriented applications – such as wind turbine blades and light-weight automotive structural components. We supply epoxy resin systems to composite fabricators in the wind energy, automotive and pipe markets. Epoxy specialty resins are also used for a variety of high-end coating applications that require the superior adhesion, corrosion resistance and durability of epoxy, such as protective coatings for industrial flooring, pipe, marine and construction applications and automotive coatings.

As noted above in Item 1A, "Risk Factors," we are subject to extensive environmental regulations, which may impose significant additional costs on our operations in the future. Further, concerns about greenhouse gas emissions and their possible effects on climate change has led to the enactment of regulations, and to proposed legislation and additional regulations, that could affect us in the form of increased cost of feedstocks and fuel, other increased costs of production and decreased demand for our products. While we do not expect any of these enactments or proposals to have a material adverse effect on us in the near term, we cannot predict the longer-term effect of any of these regulations or proposals on our future financial condition, results of operations or cash flows.

Housing and Infrastructure Products

Our Housing and Infrastructure Products segment is primarily comprised of building products, PVC pipes and fittings and PVC compound products. Our sales are affected by the individual decisions of distributors and dealers on the levels of inventory they carry, their views on product demand, their financial condition and the manner in which they choose to manage inventory risk. A significant portion of our performance in this segment is driven by the activities in the residential construction and repair and remodeling markets in North America which began to decline at the end of the second quarter of 2022 due to the negative effect that rising mortgage rates in the United States had on buyer sentiment. Performance of our housing and infrastructure products businesses over time are generally reflective of the trends of building permits and housing starts in the New Residential Construction Survey by the U.S. Census Bureau and the Repair and Remodeling Index (RRI) provided by the National Association of Home Builders (the "NAHB") among others. Although we ultimately expect that the Infrastructure Investment and Jobs Act of 2021 and historically low residential housing construction may have a favorable long-term impact on certain industries related to our Housing and Infrastructure Products segment, the current inflationary environment impacting consumer spending and priorities, the possibility of recession or financial market instability, rapidly rising interest rates, decade high mortgage interest rates impacting consumer affordability, and ongoing labor and supply chain constraints are expected to have an unfavorable impact on the demand for housing construction in the near term and, as a result, our products produced by this segment.

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The following table presents annual historical housing starts per the U.S. Census Bureau and the 2023 and 2024 outlook per the NAHB:

North American PVC facilities within the Performance and Essential Materials segment supply most of the PVC required for our building products and PVC pipes and fittings plants. Our raw materials for stone, roofing and accessories, windows, shutters and specialty tool products are externally purchased. PVC required for the PVC compounds plants is either internally sourced from our North American and Asian facilities within the Performance and Essential Materials segment or externally purchased based on the location of the plants. The remaining feedstocks required, including pigments, fillers, stabilizers and other ingredients, are purchased under short-term contracts based on prevailing market prices.

During the fourth quarter of 2021, we completed the acquisition of Boral's North American building products businesses in roofing, siding, trim and shutters, decorative stone and windows (the "Boral Target Companies") for $2,140 million. During the third quarter of 2021, we completed the acquisitions of LASCO Fittings, Inc. ("LASCO"), a manufacturer of injected-molded PVC fittings that serve the plumbing, pool and spa, industrial, irrigation and retail markets in the United States, for $277 million, and DX Acquisition Corp. ("Dimex"), a producer of various consumer products made from post-industrial-recycled PVC, polyethylene and thermoplastic elastomer materials, including, landscape edging; industrial, home and office matting; marine dock edging; and masonry joint controls, for $172 million. The results of operations for these acquired businesses are included in the Housing and Infrastructure Products segment.

Factors that have caused volatility in our raw material prices, energy costs and production processes in the past, and which may do so in the future, include significant fluctuation in prices of these raw materials in response to, among other things, variable worldwide supply and demand across different industries, speculation in commodities futures, general economic, business or environmental conditions, labor costs, competition, import duties, tariffs, worldwide currency fluctuations, freight, inflationary pressures, regulatory costs, and product and process evolutions that impact demand for the same materials. Increasing raw material prices directly impact our cost of sales and our ability to maintain margins depends on implementing price increases in response to increasing raw material costs. The market for our products may or may not accept price increases, and as such, our future financial condition, results of operations or cash flows could be materially impacted.

Non-GAAP Financial Measures

The body of accounting principles generally accepted in the United States is commonly referred to as "GAAP." For this purpose, a non-GAAP financial measure is generally defined by the Securities and Exchange Commission ("SEC") as one that purports to measure historical or future financial performance, financial position or cash flows that (1) excludes amounts, or is subject to adjustments that have the effect of excluding amounts, that are included in the most directly comparable measure calculated and presented in accordance with GAAP in the statement of income, balance sheet or statement of cash flows (or equivalent statements) of the registrant; or (2) includes amounts, or is subject to adjustments that have the effect of including amounts, that are excluded from the most directly comparable measure so calculated and presented. In this report, we disclose non-GAAP financial measures, primarily earnings before interest, taxes, depreciation and amortization ("EBITDA") and Free Cash Flow. We define EBITDA as net income before interest expense, income taxes, depreciation and amortization. We define Free Cash Flow as net cash provided by operating activities less additions to property, plant and equipment. The non-GAAP financial measures described in this Form 10-K are not substitutes for the GAAP measures of earnings and cash flows.

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EBITDA is included in this Form 10-K because our management considers it an important supplemental measure of our performance and believes that it is frequently used by securities analysts, investors and other interested parties in the evaluation of companies in our industry, some of which present EBITDA when reporting their results. We regularly evaluate our performance as compared to other companies in our industry that have different financing and capital structures and/or tax rates by using EBITDA. In addition, we utilize EBITDA in evaluating acquisition targets. Management also believes that EBITDA is a useful tool for measuring our ability to meet our future debt service and satisfy capital expenditure and working capital requirements, and EBITDA is commonly used by us and our investors to measure our ability to service indebtedness.

Free Cash Flow is included in this Form 10-K because our management considers it an important supplemental measure of our performance and believes that it is frequently used by securities analysts, investors and other interested parties in the evaluation of companies in our industry, some of which present Free Cash Flow when reporting their results. We regularly evaluate our performance as compared to other companies in our industry that have different financing and capital structures and/or tax rates by using Free Cash Flow. Management also believes that Free Cash Flow is useful to investors and securities analysts to evaluate our liquidity, evaluate strategic investment, evaluate our stock buyback plan and measure our ability to meet our future debt service.

EBITDA and Free Cash Flow are not substitutes for the GAAP measures of net income, income from operations and net cash provided by operating activities and are not necessarily measures of our ability to fund our cash needs. In addition, companies calculate EBITDA and Free Cash Flow differently and, therefore, EBITDA and Free Cash Flow as presented for us may not be comparable to EBITDA and Free Cash Flow reported by other companies. EBITDA has material limitations as a performance measure because it excludes interest expense, depreciation and amortization and income taxes. Free Cash Flow has material limitations as a performance measure because it only considers net cash provided by operating activities, and not net income or income from operations. For instance, it applies the entire cost of capital expenditure in the period in which the property or equipment is acquired, rather than spreading it over several periods as is the case with net income and income from operations.

Reconciliations of EBITDA to net income, income from operations and net cash provided by operating activities, and Free Cash Flow to net cash provided by operating activities, are included in the "Results of Operations" section below.

Significant Developments

COVID-19, Industry Conditions and Our Business

On March 11, 2020, the World Health Organization declared the ongoing COVID-19 outbreak a pandemic and recommended containment and mitigation measures worldwide. The pandemic resulted in widespread adverse impacts on the global economy. We experienced significant disruptions in the second quarter of 2020 as the pandemic and its impact on the global economy spread through most of our markets. Though government restrictions across most countries generally eased through the end of 2021, there is considerable uncertainty regarding the potential resurgence of COVID-19 pandemic and the extent and duration of governmental and other measures that could be re-implemented to try to slow the spread of the virus. Considering the uncertain and volatile nature of the COVID-19 pandemic, we could experience significant disruptions to our business operations in the future.

Hexion Global Epoxy Business Acquisition

On February 1, 2022, we completed the acquisition of the global epoxy business of Hexion Inc. ("Westlake Epoxy") for a purchase consideration of $1,207 million, as discussed above under the Performance and Essential Materials segment.

Acquisition of Additional LACC Interests

In January 2022, we notified Lotte Chemical Corporation ("Lotte") of the exercise of the option to acquire an additional 3.2% of the membership interests in LACC, LLC ("LACC") from Lotte. The acquisition was completed on March 15, 2022 for $89 million. As of December 31, 2022, we owned an aggregate 50% membership interest in LACC.

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Redemption of 3.60% Senior Notes Due 2022

In April 2022, we provided notice to the trustee of the 3.60% senior notes due 2022 (the "3.60% 2022 Senior Notes") that we had elected to redeem all of the outstanding 3.60% 2022 Senior Notes on May 14, 2022 (the "Redemption Date") pursuant to our optional redemption right under the indenture governing the 3.60% 2022 Senior Notes. The 3.60% 2022 Senior Notes were redeemed on May 14, 2022. The redemption price was equal to 100% of the principal amount of the 3.60% 2022 Senior Notes, plus accrued and unpaid interest on the 3.60% 2022 Senior Notes to the Redemption Date.

New Credit Agreement

On June 9, 2022, we entered into a new $1.5 billion revolving credit facility that is scheduled to mature on June 9, 2027 (the "New Credit Agreement") and, in connection therewith, terminated our existing revolving credit agreement. The New Credit Agreement bears interest at either (a) Adjusted Term Secured Overnight Financing Rate ("SOFR") (as defined in the New Credit Agreement) plus a margin ranging from 1.00% to 1.625% per annum or (b) Alternate Base Rate (as defined in the New Credit Agreement) plus a margin ranging from 0.00% to 0.625% per annum, in each case depending on the credit rating of the Company. The New Credit Agreement contains certain affirmative and negative covenants, including a quarterly total leverage ratio financial maintenance covenant.

Expansion of Share Repurchase Program

On August 12, 2022, our Board of Directors authorized the Company to repurchase an additional $500 million of shares of its common stock under its existing share repurchase program.

Inflation Reduction Act of 2022

On August 16, 2022, the Inflation Reduction Act of 2022 (the "IRA") was signed into law. The IRA contains several revisions to the Internal Revenue Code, including a 15% corporate minimum income tax for corporations with average annual adjusted financial statement income over a three-tax-year period in excess of $1 billion and is effective for the tax years beginning after December 31, 2022, a 1% excise tax on stock repurchases made by publicly traded U.S. corporations after December 31, 2022, and business tax credits and incentives for the development of clean energy projects and the production of clean energy. At this time, we do not expect the IRA will have a material impact on our consolidated financial statements. We continue to evaluate its impact as new information and guidance becomes available.

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Results of Operations

Segment Data

The table below and descriptions that follow represent the consolidated results of operations of the Company for the years ended December 31, 2022, 2021 and 2020.

Net External Sales

The table below presents net external sales on a disaggregated basis for our two principal operating segments. Performance Materials net external sales primarily consist of sales of PVC, polyethylene and epoxy. Essential Materials net external sales primarily consist of sales of caustic soda, styrene, and related derivative materials. Housing Products net external sales primarily consist of sales of housing exterior and interior products, residential pipes and fittings and residential PVC compounds. Infrastructure Products net external sales primarily consist of sales of non-residential pipes and fittings and non-residential PVC compounds.

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(1)See above for discussions on non-GAAP financial measures. See "Reconciliation of EBITDA to Net Income, Income from Operations and Net Cash Provided by Operating Activities" below.

(2)See above for discussions on non-GAAP financial measures. See "Reconciliation of Free Cash Flow to Net Cash Provided by Operating Activities" below.

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Reconciliation of EBITDA to Net Income, Income from Operations and Net Cash Provided by Operating Activities

The following table presents the reconciliation of EBITDA to net income, income from operations and net cash provided by operating activities, the most directly comparable GAAP financial measures, for each of the periods indicated.

Reconciliation of Free Cash Flow to Net Cash Provided by Operating Activities

The following table presents the reconciliation of Free Cash Flow to net cash provided by operating activities, the most directly comparable GAAP financial measure, for each of the periods indicated.

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2022 Compared with 2021

Summary

For the year ended December 31, 2022, net income attributable to Westlake Corporation was $2,247 million, or $17.34 per diluted share, on net sales of $15,794 million. This represents an increase in net income attributable to Westlake Corporation of $232 million, or $1.76 per diluted share, compared to 2021 net income attributable to Westlake Corporation of $2,015 million, or $15.58 per diluted share, on net sales of $11,778 million. Income from operations was $3,050 million for the year ended December 31, 2022, as compared to $2,800 million for the year ended December 31, 2021, an increase of $250 million. The increase in net income and income from operations was primarily due to significantly higher global sales prices for caustic soda and chlorine caused by higher demand through the year, and higher prices and margins on many of our products in the Housing and Infrastructure Products segment, due to strong demand for our products primarily during the first half of 2022. In addition, net income and income from operations included the contributions from the businesses acquired in the second half of 2021 and in the first quarter of 2022. Net income and income from operations for the year ended December 31, 2022 was negatively impacted by softening demand for PVC resin during the second half of 2022 due to slowing global economic conditions. In addition, higher natural gas, power and feedstock costs and a $70 million pre-tax litigation charge negatively impacted net income and income from operations during the year ended December 31, 2022. Selling, general and administrative expenses were also higher for the year ended December 31, 2022 primarily due to the businesses acquired in the second half of 2021 and in the first quarter of 2022. Net sales increased by $4,016 million to $15,794 million in 2022 from $11,778 million in 2021, due to higher sales prices for caustic soda and chlorine and for many of our products in the Housing and Infrastructure Products segment, partially offset by lower polyethylene sales prices. Sales volumes in the year ended December 31, 2022 were also higher in both segments as compared to the year ended December 31, 2021, primarily due to the contributions from the acquired businesses in the second half of 2021 and in the first quarter of 2022, partially offset by lower PVC resin, caustic soda and PVC compounds sales volumes.

Net Sales. Net sales increased by $4,016 million, or 34%, to $15,794 million in 2022 from $11,778 million in 2021, primarily due to higher sales prices for caustic soda and chlorine and for many of our products in the Housing and Infrastructure Products segment as well as higher sales volumes due to the businesses acquired in the second half of 2021 and in the first quarter of 2022, partially offset by lower polyethylene sales prices. Average sales prices for 2022 increased by 20% as compared to 2021 due to strong demand for caustic soda and strong residential construction, repair and remodeling markets in North America during the first half of 2022. Sales volumes increased by 14% in 2022 as compared to 2021, primarily due to the businesses acquired in the second half of 2021 and in the first quarter of 2022, partially offset by lower PVC resin, caustic soda and PVC compounds sales volumes.

Gross Profit. Gross profit margin percentage was 26% in 2022 as compared to 30% in 2021. The decline in gross margin percentage for the year ended December 31, 2022 as compared to the year ended December 31, 2021 was primarily due to higher natural gas, power, feedstock and raw material costs and lower polyethylene sales prices. These decreases versus the prior year were partially offset by higher sales prices for caustic soda, chlorine, derivative products, pipes and fittings and PVC compounds.

Selling, General and Administrative Expenses. Selling, general and administrative expenses increased by $284 million to $835 million in 2022 from $551 million in 2021. This increase was mainly due to the inclusion of expenses related to the businesses acquired in the second half of 2021 and in the first quarter of 2022 as well as higher employee-related costs.

Amortization of Intangibles. Amortization expense increased by $32 million to $155 million in 2022 from $123 million in 2021, primarily due to the amortization of intangibles associated with the businesses acquired in the second half of 2021 and in the first quarter of 2022.

Restructuring, Transaction and Integration-related Costs. The restructuring, transaction and integration-related costs of $33 million and $21 million for the years ended December 31, 2022 and December 31, 2021, respectively, primarily consisted of restructuring, transaction and integration-related costs associated with the businesses acquired in the second half of 2021 and in the first quarter of 2022.

Interest Expense. Interest expense of $177 million in 2022 was comparable to $176 million in 2021. The full year interest expense in 2022 associated with the issuance of $1,700 million aggregate principal amount of senior notes in August 2021 was substantially offset by the realization of losses in 2021 on the settlement of interest rate lock arrangements associated with the senior notes issued in August 2021.

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Other Income, Net. Other income, net of $73 million in 2022 was higher than other income, net of $53 million in 2021, primarily due to higher interest income.

Income Taxes. The effective income tax rate was 22% in 2022, which was slightly lower than the 23% effective tax rate in 2021. The effective tax rate in 2022 was lower as compared to 2021, primarily due to an increase in U.S. federal research and development credits available to the Company in 2022.

Performance and Essential Materials Segment

Net Sales. Net sales for the Performance and Essential Materials segment increased by $2,338 million, or 27%, to $11,008 million in 2022 from $8,670 million in 2021. Average sales prices for the Performance and Essential Materials segment increased by 15% in 2022 as compared to 2021. The increase in average sales prices were primarily driven by higher prices for caustic soda, chlorine and derivative products, partially offset by lower polyethylene sales prices. Sales volumes for the Performance and Essential Materials segment increased by 13% in 2022 as compared to 2021, primarily due to contributions from the recently acquired Westlake Epoxy business, which were partially offset by lower PVC resin, caustic soda and styrene sales volumes.

Income from Operations. Income from operations for the Performance and Essential Materials segment decreased by $133 million to $2,416 million in 2022 from $2,549 million in 2021. This decrease in income from operations was primarily due to lower polyethylene sales prices and integrated margins and lower sales volumes for PVC resin and caustic soda, higher natural gas, power and feedstock costs and a $70 million pre-tax litigation charge in the third quarter of 2022. The decrease in income from operations versus the prior-year was partially offset by higher sales prices for caustic soda, chlorine and derivative products and income from Westlake Epoxy, which was acquired in the first quarter of 2022. Trading activity in 2022 resulted in a loss of approximately $28 million as compared to a gain of $12 million in 2021.

Housing and Infrastructure Products Segment

Net Sales. Net sales for the Housing and Infrastructure Products segment increased by $1,678 million, or 54%, to $4,786 million in 2022 from $3,108 million in 2021. Housing Products net sales of $3,864 million increased by $1,530 million as compared to 2021 primarily due to higher sales prices for all products as well as a full year of sales contribution from the businesses acquired in the second half of 2021. Infrastructure Products net sales of $922 million increased by $148 million as compared to 2021 primarily due to significantly higher sales prices. Average sales prices for the Housing and Infrastructure Products segment increased by 35% in 2022 as compared to 2021, primarily due to strong residential construction and repair and remodeling activity during the first half of 2022. Sales volumes for the Housing and Infrastructure Products segment increased by 19% in 2022, as compared to 2021, primarily due to contributions from the businesses acquired in the second half of 2021, partially offset by lower sales volumes for PVC compounds.

Income from Operations. Income from operations for the Housing and Infrastructure Products segment increased by $319 million to $675 million in 2022 from $356 million in 2021. The increase in income from operations was primarily due to higher sales prices driven by higher housing construction and remodeling activity during the first half of 2022. Income from operations was also higher due to contributions from the businesses acquired in the second half of 2021. The higher income from operations in 2022 as compared to 2021 was partially offset by higher raw material, power and production costs.

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2021 Compared with 2020

Summary

For the year ended December 31, 2021, net income attributable to Westlake Corporation was $2,015 million, or $15.58 per diluted share, on net sales of $11,778 million. This represents an increase in net income attributable to Westlake Corporation of $1,685 million, or $13.02 per diluted share, as compared to 2020 net income attributable to Westlake Corporation of $330 million, or $2.56 per diluted share, on net sales of $7,504 million. Income from operations was $2,800 million for the year ended December 31, 2021 as compared to $429 million for the year ended December 31, 2020, an increase of $2,371 million. The increase in net income and income from operations was primarily due to significantly higher global sales prices and integrated margins for our major products due to the strengthening of demand for our products resulting from continued improvement in global economic activity from the severe impact of the COVID-19 pandemic in 2020, strong residential construction and repair and remodeling markets in North America and strong demand from the packaging and other consumer markets. Net income and income from operations for the year ended December 31, 2021 were positively impacted by higher margin contribution on ethylene produced by LACC. Net income and income from operations for the year ended December 31, 2021 was negatively impacted by higher feedstock costs, fuel costs and selling, general and administrative expense. Net income for the year ended December 31, 2020 included an income tax rate benefit of $95 million resulting from the carryback of federal net operating losses permitted by the Coronavirus Aid, Relief, and Economic Security Act (the "CARES Act"). Net sales increased by $4,274 million to $11,778 million in 2021 from $7,504 million in 2020, mainly due to higher sales prices for our major products as well as higher sales volumes for Housing and Infrastructure Products due to our acquisitions in 2021.

Net Sales. Net sales increased by $4,274 million, or 57%, to $11,778 million in 2021 from $7,504 million in 2020, primarily attributable to higher sales prices for our major products as well as higher sales volumes for Housing and Infrastructure Products due to our acquisitions in 2021. Average sales prices for 2021 increased by 51% as compared to 2020 due to the strong demand for our products resulting from continued improvement in global economic activity, strong residential construction, repair and remodeling markets in North America, and strong demand from the packaging and other consumer markets. Sales volumes increased by 6% in 2021 as compared to 2020, primarily due to the acquisitions in 2021.

Gross Profit. Gross profit margin percentage increased to 30% in 2021 from 14% in 2020. The increase in gross profit margin was primarily due to higher sales prices and margins for our major products. Gross profit margin for the year ended December 31, 2021 was also positively impacted by the margin contributed from LACC's produced ethylene. Gross profit margin for the year ended December 31, 2021 was negatively impacted by higher feedstock and fuel costs.

Selling, General and Administrative Expenses. Selling, general and administrative expenses increased by $102 million to $551 million in 2021 from $449 million in 2020. This increase was mainly due to higher employee compensation, selling and consulting expenses and the inclusion of expenses related to the acquisitions in 2021.

Amortization of Intangibles. Amortization expense increased by $14 million to $123 million in 2021 from $109 million for 2020, primarily due to the amortization of intangibles associated with the acquisitions in 2021.

Restructuring, Transaction and Integration-related Costs. Restructuring, transaction and integration-related costs were $21 million in 2021 as compared to $36 million in 2020. The restructuring, transaction and integration-related costs of $21 million for the year ended December 31, 2021 primarily consisted of costs associated with the acquisitions in 2021. Restructuring, transaction and integration-related costs of $36 million in the year ended December 31, 2020 was primarily related to the closure of a non-integrated PVC plant located in Germany and included the $8 million write-off of certain assets and other expenses associated with the plant closure.

Interest Expense. Interest expense increased by $34 million to $176 million in 2021 from $142 million in 2020, primarily as a result of higher average debt outstanding in 2021 as compared to the year ended December 31, 2020 and the settlement of interest rate lock arrangements associated with the issuance of the Notes. See "Liquidity and Capital Resources—Debt" below and Note 11 to the consolidated financial statements included in this Form 10-K for further discussion of our indebtedness.

Other Income, Net. Other income, net of $53 million in 2021 was higher as compared to other income, net of $44 million in 2020. This increase was primarily due to higher expected return on pension plan assets.

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Income Taxes. The effective income tax rate was an expense of 23% in 2021 as compared to a benefit of 13% in 2020. The change in effective tax rate in 2021 as compared to 2020 was primarily due to the income tax rate benefit in the year ended December 31, 2020 resulting from the carryback of federal net operating loss to taxable years that were taxed at the U.S. corporate tax rate of 35% as permitted under the CARES Act, partially offset by the reduction in the Section 199 domestic manufacturing deduction as a result of the net operating loss carryback.

Performance and Essential Materials Segment

Net Sales. Net sales for the Performance and Essential Materials segment increased by $3,205 million, or 59%, to $8,670 million in 2021 from $5,465 million in 2020. Average sales prices for the Performance and Essential Materials segment increased by 58% in 2021 as compared to 2020. The higher Performance Materials sales prices were due to higher polyethylene and PVC resin sales prices. The higher Essential Materials sales prices were primarily driven by the higher prices for caustic due to improved global economic activity. Sales volumes for the Performance and Essential Materials segment remained relatively consistent in 2021 as compared to 2020.

Income from Operations. Income from operations for the Performance and Essential Materials segment increased by $2,318 million to $2,549 million in 2021 from $231 million in 2020. This increase in income from operations was primarily due to higher sales prices and margins for polyethylene, PVC resin and caustic soda, mainly resulting from the continued improvement in global economic activity from the severe impact of the COVID-19 pandemic in 2020. The increase in income from operations as compared to the prior year was negatively impacted by higher feedstock and fuel costs. Income from operations for the year ended December 31, 2021 was also impacted by Winter Storm Uri and Hurricane Ida, while income from operations for the year ended December 31, 2020 was negatively impacted by the onset of the COVID-19 pandemic and Hurricanes Laura and Delta.

Housing and Infrastructure Products Segment

Net Sales. Net sales for the Housing and Infrastructure Products segment increased by $1,069 million, or 52%, to $3,108 million in 2021 from $2,039 million in 2020. In addition to the net sales from the businesses we acquired in the second half of 2021, the increase in net sales was also driven by higher sales prices for our major products in the housing and infrastructure businesses. Average sales prices increased by 33% from 2020 to due to strong demand for our major products in the residential construction and repair and remodeling markets. Sales volumes for the Housing and Infrastructure Products segment increased by 19% in 2021 as compared to 2020 due to strong demand as well as the businesses we acquired in the second half of 2021.

Income from Operations. Income from operations for the Housing and Infrastructure Products segment increased by $100 million to $356 million in 2021 from $256 million in 2020. The increase in income from operations was primarily due to significantly higher sales prices and margins driven by robust housing construction and remodeling activity resulting from the continued economic recovery from the COVID-19 pandemic. Additionally, 2021 experienced higher energy costs as well as the impacts from Winter Storm Uri and Hurricane Ida, while income from operations for the year ended December 31, 2020 was negatively impacted by the onset of the COVID-19 pandemic and Hurricanes Laura and Delta.

Cash Flows

Operating Activities

Operating activities provided cash of $3,395 million in 2022 as compared to cash provided by operating activities of $2,394 million in 2021. The $1,001 million increase in cash flow from operating activities was mainly due to the increase in income from operations and favorable working capital changes. Changes in components of working capital, which we define for purposes of this cash flow discussion as accounts receivable, inventories, prepaid expenses and other current assets, less accounts payable and accrued and other liabilities, provided cash of $174 million in 2022, as compared to $383 million of cash used in 2021, a favorable change of $557 million. The majority of the favorable changes in 2022 were driven by a favorable change in accounts receivable, partially offset by unfavorable changes in accounts payable and accrued and other liabilities. The favorable change in accounts receivable was primarily driven by lower sales prices and volumes in the second half of 2022 due to overall softening of demand in markets we serve. The unfavorable changes in accounts payable and accrued and other liabilities in 2022 were primarily driven by lower operating activity in the second half of 2022, as compared to 2021.

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Operating activities provided cash of $2,394 million in 2021 as compared to cash provided by operating activities of $1,297 million in 2020. The $1,097 million increase in cash flows from operating activities was mainly due to the increase in income from operations, which was partially offset by working capital changes and an unfavorable change related to the turnaround at OpCo's Petro 2 facility and other turnaround activities. Changes in components of working capital, which we define for purposes of this cash flow discussion as accounts receivable, inventories, prepaid expenses and other current assets, less accounts payable and accrued and other liabilities, used cash of $383 million in 2021, as compared to $17 million of cash used in 2020, an unfavorable change of $366 million. The majority of the unfavorable changes in 2021 were driven by higher accounts receivable and higher inventories, partially offset by higher accounts payable and accrued and other liabilities. The unfavorable change in accounts receivable was primarily driven by higher sales prices resulting in higher trade customer balances. The higher inventories, accounts payable and accrued and other liabilities in 2021 were primarily driven by higher inventory cost and an increase in operating activities, as compared to 2020.

Investing Activities

Net cash used for investing activities during 2022 was $2,479 million as compared to net cash used of $3,213 million in 2021. The investing activities during 2022 were comprised primarily of the acquisition of Westlake Epoxy in February 2022 for $1,163 million, the purchase of an additional 3.2% interest in LACC for $89 million, aggregate contributions of $87 million to LACC, capital expenditures, and other asset acquisitions. Our 2021 acquisition related activities were higher, as compared to the current year, due to the acquisitions of the Boral Target Companies, LASCO and Dimex for $2,554 million in the aggregate. Capital expenditures were $1,108 million in 2022 compared to $658 million in 2021. Capital expenditures in 2022 and 2021 were primarily related to expansion projects at various chlor-alkali plants as well as projects to improve production capacity or reduce costs, maintenance and safety projects and environmental projects at our various facilities.

Net cash used for investing activities during 2021 was $3,213 million as compared to net cash used of $509 million in 2020. The increase in investing activities in 2021 was primarily due to the acquisitions of the Boral Target Companies, LASCO and Dimex for $2,554 million in the aggregate, net of cash acquired. Capital expenditures were $658 million in 2021 compared to $525 million in 2020. The higher capital expenditures in 2021 were primarily associated with the turnaround at OpCo's Petro 2 facility. Capital expenditures in 2021 and 2020 were primarily related to projects to improve production capacity or reduce costs, maintenance and safety projects and environmental projects at our various facilities. During 2021, we contributed $22 million to LACC and $2 million to an unconsolidated investee compared to a net return of investment of $40 million from LACC in 2020.

Financing Activities

Net cash used by financing activities during 2022 was $587 million as compared to net cash provided by financing activities of $1,437 million in 2021. The activities during 2022 were primarily related to the redemption of $250 million aggregate principal amount of the 3.60% 2022 Senior Notes, the $169 million payment of cash dividends, the $60 million payment of cash distributions to noncontrolling interests and repurchases of our common stock for an aggregate purchase price of $101 million.

Net cash provided by financing activities during 2021 was $1,437 million as compared to net cash used of $216 million in 2020. The activities during 2021 were primarily related to the registered public offering of $300 million aggregate principal amount of the 0.875% 2024 Senior Notes, $350 million aggregate principal amount of the 2.875% 2041 Senior Notes, $600 million aggregate principal amount of the 3.125% 2051 Senior Notes and $450 million aggregate principal amount of the 3.375% 2061 Senior Notes and the payment of debt issuance costs of $18 million related to the Notes. The remaining activities in 2021 were primarily related to the $145 million payment of cash dividends, the $48 million payment of cash distributions to noncontrolling interests and repurchases of our common stock for an aggregate purchase price of $30 million.

Liquidity and Capital Resources

Liquidity and Financing Arrangements

Our principal sources of liquidity are from cash and cash equivalents, cash from operations, short-term borrowings under the New Credit Agreement and our long-term financing.

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In November 2014, our Board of Directors authorized a $250 million stock repurchase program (the "2014 Program"). In November 2015, our Board of Directors approved the expansion of the 2014 Program by an additional $150 million. In August 2018, our Board of Directors approved the further expansion of the existing 2014 Program by an additional $150 million. In August 2022, our Board of Directors approved the further expansion of the existing 2014 Program by an additional $500 million. As of December 31, 2022, we had repurchased 8,511,256 shares of our common stock for an aggregate purchase price of approximately $551 million under the 2014 Program. During the year ended December 31, 2022, 1,079,736 shares of our common stock were repurchased for an aggregate purchase price of $102 million under the 2014 Program. Purchases under the 2014 Program may be made either through the open market or in privately negotiated transactions. Decisions regarding the amount and the timing of purchases under the 2014 Program will be influenced by our cash on hand, our cash flows from operations, general market conditions and other factors. The 2014 Program may be discontinued by our Board of Directors at any time.

On October 4, 2018, Westlake Partners and Westlake Partners GP, the general partner of Westlake Partners, entered into an Equity Distribution Agreement with UBS Securities LLC, Barclays Capital Inc., Citigroup Global Markets Inc., Deutsche Bank Securities Inc., RBC Capital Markets, LLC, Merrill Lynch, Pierce, Fenner & Smith Incorporated and Wells Fargo Securities, LLC to offer and sell Westlake Partners common units, from time to time, up to an aggregate offering amount of $50 million. This Equity Distribution Agreement was amended on February 28, 2020 to reference a new shelf registration for utilization under this agreement. No common units were issued under this program in 2022, 2021 or 2020.

We believe that our sources of liquidity as described above are adequate to fund our normal operations and ongoing capital expenditures. Funding of any potential large expansions such as our recent acquisitions or potential future acquisitions or the repayment of debt may likely necessitate, and therefore depend on our ability to obtain, additional financing in the future. We may not be able to access additional liquidity at favorable interest rates due to volatility of the commercial credit market.

Cash and Cash Equivalents

As of December 31, 2022, our cash and cash equivalents totaled $2,228 million.

In addition to our cash and cash equivalents, our New Credit Agreement is available to provide liquidity as needed, as described under "Debt" below.

Debt

As of December 31, 2022, our indebtedness totaled $4,879 million. See Note 11 to the consolidated financial statements appearing elsewhere in this Form 10-K for a discussion of our long-term indebtedness. Defined terms used in this section have the definitions assigned to such terms in Note 11 to the consolidated financial statements included in Item 8 of this Form 10-K.

Our ability to make payments on our indebtedness and to fund planned capital expenditures will depend on our ability to generate cash in the future, which is subject to general economic, financial, competitive, legislative, regulatory and other factors that are beyond our control. Based on our current level of operations and unless we were to undertake a new expansion or large acquisition, we believe our cash flows from operations, available cash and available borrowings under our New Credit Agreement will be adequate to meet our normal operating needs for the foreseeable future.

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Our long-term debt consisted of the following as of December 31, 2022:

______________________________

(1)    At our option, we may redeem the notes at any time on or after the specified par call date at a redemption price equal to 100% of the principal amount of the notes being redeemed plus accrued and unpaid interest.

(2)    At our option, we may redeem the notes at any time prior to the specified par call date at a redemption price equal to the greater of (i) 100% of the principal amount of the notes being redeemed plus accrued and unpaid interest and (ii) the sum of the present values of the remaining scheduled payments on the notes being redeemed that would be due if the notes matured on the specified par call date, discounted to the redemption date on an annual basis at the applicable comparable government bond rate plus 30 basis points plus accrued and unpaid interest.

(3)    At our option, we may redeem the notes at any time prior to the specified par call date at a redemption price equal to the greater of (i) 100% of the principal amount of the notes being redeemed plus accrued and unpaid interest and (ii) the sum of the present values of the remaining scheduled payments on the notes being redeemed that would be due if the notes matured on the specified par call date, discounted to the redemption date on a semi-annual basis at the treasury rate plus 20 to 45 basis points plus accrued and unpaid interest.

(4)    In the event of a redemption of certain bonds (the "GO Zone Bonds") issued by the Louisiana Local Government Environmental Facility and Development Authority (the "Authority") in 2017, we will redeem notes equal in principal amount to the GO Zone Bonds to be redeemed at a redemption price equal to the redemption price of the GO Zone Bonds to be redeemed, plus accrued interest to the redemption date. The GO Zone Bonds are subject to optional redemption by the Authority upon the direction of the Company at any time on or after November 1, 2027, for 100% of the principal amount plus accrued interest to the redemption date.

(5)    The waste disposal revenue bonds expire in December 2027 and are subject to redemption and mandatory tender for purchase prior to maturity under certain conditions.

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The holders of the 0.875% 2024 Senior Notes, the 3.60% 2026 Senior Notes, the 1.625% 2029 Senior Notes, the 3.375% 2030 Senior Notes, the 3.50% 2032 GO Zone Refunding Senior Notes, the 2.875% 2041 Senior Notes, the 5.00% 2046 Senior Notes, the 4.375% 2047 Senior Notes, the 3.125% 2051 Senior Notes and the 3.375% 2061 Senior Notes may require us to repurchase the notes at a price equal to 101% of their principal amount, plus accrued and unpaid interest to, but not including, the date of repurchase, upon the occurrence of both a "change of control" and, within 60 days of such change of control, a "below investment grade rating event" (as such terms are defined in the respective indentures governing these notes).

The indenture governing the 0.875% 2024 Senior Notes, the 3.60% 2026 Senior Notes, the 1.625% 2029 Senior Notes, the 3.375% 2030 Senior Notes, the 3.50% 2032 GO Zone Refunding Senior Notes, the 2.875% 2041 Senior Notes, the 5.00% 2046 Senior Notes, the 4.375% 2047 Senior Notes, the 3.125% 2051 Senior Notes, and the 3.375% 2061 Senior Notes contains customary events of default and covenants that, among other things and subject to certain exceptions, restrict us and certain of our subsidiaries' ability to (1) incur certain secured indebtedness, (2) engage in certain sale and leaseback transactions and (3) consolidate, merge or transfer all or substantially all of our assets.

In July 2012, we issued $250 million aggregate principal amount of 3.60% Senior Notes due 2022 (the "3.60% 2022 Senior Notes"). During April 2022, we provided notice to the trustee that we had elected to redeem all of the outstanding 3.60% 2022 Senior Notes on May 14, 2022 (the "Redemption Date") pursuant to our optional redemption right under the indenture governing the 3.60% 2022 Senior Notes. The 3.60% 2022 Senior Notes were redeemed on May 14, 2022 at a redemption price equal to 100% of the principal amount of the 3.60% 2022 Senior Notes, plus accrued and unpaid interest on the 3.60% 2022 Senior Notes to the Redemption Date.

As of December 31, 2022, we were in compliance with all of our long-term debt covenants.

New Credit Agreement

On June 9, 2022, we entered into a new $1.5 billion revolving credit facility that is scheduled to mature on June 9, 2027 (the "New Credit Agreement") and, in connection therewith, terminated our existing revolving credit agreement. The New Credit Agreement bears interest at either (a) Adjusted Term SOFR (as defined in the New Credit Agreement) plus a margin ranging from 1.00% to 1.625% per annum or (b) Alternate Base Rate (as defined in the New Credit Agreement) plus a margin ranging from 0.00% to 0.625% per annum, in each case depending on the credit rating of the Company. The New Credit Agreement contains certain affirmative and negative covenants, including a quarterly total leverage ratio financial maintenance covenant. As of December 31, 2022, we were in compliance with the total leverage ratio financial maintenance covenant.

The New Credit Agreement also contains certain events of default and, if and for so long as certain events of default have occurred and are continuing, any overdue amounts outstanding under the New Credit Agreement will accrue interest at an increased rate, the lenders can terminate their commitments to lend thereunder and payments of any outstanding amounts thereunder could be accelerated by the lenders. None of our subsidiaries are required to guarantee our obligations under the New Credit Agreement.

The New Credit Agreement includes a $150 million sub-limit for letters of credit, and any outstanding letters of credit will be deducted from availability under the facility. The New Credit Agreement also provides for a discretionary $50 million commitment for swingline loans to be provided on a same-day basis. We may also increase the size of the facility, in increments of at least $25 million, up to a maximum of $500 million, subject to certain conditions and if certain lenders agree to commit to such an increase.

Westlake Chemical Partners LP Credit Arrangements

Our subsidiary, Westlake Chemical Finance Corporation, is the lender party to a $600 million revolving credit facility with Westlake Chemical Partners LP ("Westlake Partners") (the "MLP Revolver") that is scheduled to mature on July 12, 2027. As of December 31, 2022, outstanding borrowings under the credit facility totaled $377 million and bore interest at Secured Overnight Financing Rate, as administered by the Federal Reserve Bank of New York ("SOFR") plus the Applicable Margin plus a 0.10% credit spread adjustment. On July 12, 2022, Westlake Partners entered into the Fourth Amendment (the "MLP Revolver Amendment") to the MLP Revolver. The MLP Revolver Amendment, among other things, extended the maturity date to July 12, 2027 and provided for the replacement of LIBOR with SOFR. Borrowings under the MLP Revolver now bear interest at a variable rate of either (a) SOFR plus the Applicable Margin plus a 0.10% credit spread adjustment or, if SOFR is no longer available, (b) the Alternate Base Rate plus the Applicable Margin minus 1.0%. The Applicable Margin under the MLP Revolver varies between 1.75% and 2.75%, depending on the Partnership's Consolidated Leverage Ratio.

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Our subsidiary, Westlake Polymers LLC, is the administrative agent to a $600 million revolving credit facility with Westlake Chemical OpCo LP ("OpCo") (the "OpCo Revolver") that is scheduled to mature on July 12, 2027. As of December 31, 2022, outstanding borrowings under the credit facility totaled $23 million and bore interest at SOFR plus the Applicable Margin of 1.75% plus a 0.10% credit spread adjustment. On July 12, 2022, OpCo entered into the Second Amendment (the "OpCo Revolver Amendment") to the OpCo Revolver. The OpCo Revolver Amendment, among other things, extended the maturity date to July 12, 2027 and provided for the replacement of LIBOR with SOFR. Borrowings under the OpCo Revolver now bear interest at a variable rate of either (a) SOFR plus the Applicable Margin plus a 0.10% credit spread adjustment or, if SOFR is no longer available, (b) the Alternate Base Rate plus the Applicable Margin minus 1.0%. The Applicable Margin under the OpCo Revolver is 1.75%

We consolidate Westlake Partners and OpCo for financial reporting purposes as we have a controlling financial interest. As such, the revolving credit facilities described above between our subsidiaries and Westlake Partners and OpCo are eliminated from the financial statements upon consolidation.

Contractual and Other Obligations

The Company's material cash requirements for contractual and other obligations in the near term (next 12 months) and the long term period (2024 and thereafter) include long-term debt, interest payments, operating leases, pension benefits funding, post-retirement healthcare benefits, purchase obligations, asset retirement obligations and letters of credit.

Debt Obligations and Interest Payments. As of December 31, 2022, we had no debt obligations due within the near term, and debt obligations of $4,976 million due over the long-term period. At December 31, 2022, long-term debt related interest expense of $158 million was due within the near term, and related interest expense of $2,838 million was due over the long-term period. Maturities of our debt consist of $300 million in 2024, $765 million in 2026 and $11 million in 2027. There are no other scheduled maturities of debt in 2023 through 2027. See Note 11, "Long-Term Debt," in the Notes to Consolidated Financial Statements in Item 8 of this Form 10-K for further information on our debt obligations and the expected timing of future principal and interest payments.

Operating leases. As of December 31, 2022, there was $129 million in operating lease obligations due within the near term, and $608 million due over the long-term period. See Note 7, "Leases," in the Notes to Consolidated Financial Statements in Item 8 of this Form 10-K for further detail of our obligations and the timing of expected future payments.

Pension Benefits Funding and Post-retirement Healthcare Benefits. Pension benefits funding obligations due within the near term were $12 million while post-retirement healthcare benefit payment obligations due within the near term were $9 million as of December 31, 2022. As of December 31, 2022, we had $214 million and $47 million of pension benefit funding and post-retirement healthcare benefit obligations due over the long-term period, respectively. The estimate of the timing of future payments under our defined benefit pension plans which cover certain eligible employees in the United States and non-U.S. countries and our post-retirement healthcare benefits to the employees of certain subsidiaries who meet certain minimum age and service requirements involves the use of certain assumptions, including retirement ages and payout periods. See Note 14, "Employee Benefits," in the Notes to Consolidated Financial Statements in Item 8 of this Form 10-K for further information on our obligations and the timing of expected future payments.

Purchase Obligations. Purchase obligations include agreements to purchase goods and services that are enforceable and legally binding and that specify all significant terms, including a minimum quantity and price. We are party to various obligations to purchase goods and services, including commitments to purchase various feedstock, utilities, nitrogen, oxygen, product storage, pipeline usage and logistic support, in each case in the ordinary course of our business, as well as various purchase commitments for our capital projects. As of December 31, 2022, we had $2,141 million of enforceable and legally binding purchase commitments due within the near term, and $7,220 million due over the long-term period.

Asset Retirement Obligations. As of December 31, 2022, we had no material asset retirement obligations due within the near term, and $47 million due over the long-term period. Asset retirement obligations includes the estimated costs and timing of payments to satisfy our recognized asset retirement obligations. We recognize asset retirement obligations in the period in which the liability becomes probable and reasonably estimable. Initially, the asset retirement obligation is recorded at fair value and capitalized as a component of the carrying value of the long-lived asset to which the obligation relates. See Note 1, "Description of Business and Significant Accounting Policies," in the Notes to Consolidated Financial Statements in Item 8 of this Form 10-K for further detail of our asset retirement obligations.

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Letters of Credit. As of December 31, 2022, we had $37 million standby letters of credit, made in the ordinary course of business, maturing within the near term, and no standby letters of credit maturing over the long-term period. We had no letters of credit outstanding under our New Credit Agreement.

Critical Accounting Policies and Estimates

Critical accounting policies are those that are important to our financial condition and require management's most difficult, subjective or complex judgments. Different amounts would be reported under different operating conditions or under alternative assumptions. We have evaluated the accounting policies used in the preparation of the accompanying consolidated financial statements and related notes and believe those policies are reasonable and appropriate. Our significant accounting policies are summarized in Note 1 to the consolidated financial statements appearing elsewhere in this Form 10-K.

Critical accounting estimates are those estimates made in accordance with GAAP that involve a significant level of estimation uncertainty and have had or are reasonably likely to have a material impact on our financial condition or results of operation. Our more critical accounting estimates include those related to long-lived assets, intangible assets, fair value estimates, accruals for long-term employee benefits, accounts receivable, income taxes and environmental and legal obligations. Inherent in such estimates are certain key assumptions. We periodically update the estimates used in the preparation of the financial statements based on our latest assessment of the current and projected business and general economic environment. We believe the following to be our most critical accounting estimates required for the preparation of our financial statements.

Long-Lived Assets. Key estimates related to long-lived assets include useful lives, recoverability of carrying values and existence of any retirement obligations. Such estimates could be significantly modified. The carrying values of long-lived assets could be impaired by significant changes or projected changes in supply and demand fundamentals (which would have a negative impact on operating rates or margins), new technological developments, new competitors with significant raw material or other cost advantages, adverse changes associated with the United States and world economies, the cyclical nature of the chemical and refining industries and uncertainties associated with governmental actions.

We evaluate long-lived assets for potential impairment indicators whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable, including when negative conditions such as significant current or projected operating losses exist. Our judgments regarding the existence of impairment indicators are based on legal factors, market conditions and the operational performance of our businesses. Actual impairment losses incurred could vary significantly from amounts estimated. Long-lived assets assessed for impairment are grouped at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities. Additionally, future events could cause us to conclude that impairment indicators exist and that associated long-lived assets of our businesses are impaired. Any resulting impairment loss could have a material adverse impact on our financial condition and results of operations.

The estimated useful lives of long-lived assets range from one to 40 years. Depreciation and amortization of these assets, including amortization of deferred turnaround costs, under the straight-line method over their estimated useful lives totaled $1,056 million, $840 million and $773 million in 2022, 2021 and 2020, respectively. If the useful lives of the assets were found to be shorter than originally estimated, depreciation or amortization charges would be accelerated.

We defer the costs of planned major maintenance activities, or turnarounds, and amortize the costs over the period until the next planned turnaround of the affected unit. Total costs deferred on turnarounds were $178 million, $215 million and $24 million in 2022, 2021 and 2020, respectively. As of December 31, 2022, deferred turnaround costs, net of accumulated amortization, totaled $359 million. Amortization in 2022, 2021 and 2020 of deferred turnaround costs was $80 million, $56 million and $48 million, respectively. Expensing turnaround costs as incurred would likely result in greater variability of our quarterly operating results and would adversely affect our financial position and results of operations.

Additional information concerning long-lived assets and related depreciation and amortization appears in Notes 6 and 8 to the consolidated financial statements appearing elsewhere in this Form 10-K.

Fair Value Estimates. We develop estimates of fair value to allocate the purchase price paid to acquire a business to the assets acquired and liabilities assumed in an acquisition, to assess impairment of long-lived assets, goodwill and intangible assets and to record marketable securities and pension plan assets. We use all available information to make these fair value determinations, including the engagement of third-party consultants. At December 31, 2022, our recorded goodwill was $2,161 million. In addition, we record all pension plan assets and certain marketable securities at fair value. The fair value of these items is determined by quoted market prices or from observable market-based inputs. See Note 16 to the consolidated financial statements appearing elsewhere in this Form 10-K for more information.

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Business Combinations and Intangible Assets Including Goodwill. We account for business combinations using the acquisition method of accounting, and accordingly, the assets and liabilities of the acquired business are recorded at their fair values at the date of acquisition. The excess of the purchase price over the estimated fair value is recorded as goodwill. Any changes in the estimated fair values of the net assets recorded for acquisitions prior to the finalization of more detailed analysis, but not to exceed one year from the date of acquisition, will change the amount of the purchase price allocable to goodwill. Any subsequent changes to any purchase price allocations that are material to our consolidated financial results will be adjusted in the same period's financial statements, including the effect on earnings of changes in depreciation, amortization or other income effects, if any, as a result of the change to the provisional amounts, calculated as if the accounting had been completed at the acquisition date. All acquisition costs are expensed as incurred and in-process research and development costs are recorded at fair value as an indefinite-lived intangible asset and assessed for impairment thereafter until completion, at which point the asset is amortized over its expected useful life. Separately recognized transactions associated with business combinations are generally expensed subsequent to the acquisition date. The application of business combination accounting requires the use of significant estimates and assumptions. Our estimates of fair value are based upon assumptions we believe to be reasonable, but which are inherently uncertain and unpredictable. The fair value of the customer relationships acquired are estimated by management through a discounted cash flow model using the multi-period excess earnings methodology, which involves the use of significant estimates and assumptions related to revenue growth rates, operating margins, discount rates, and customer attrition rates, among other items. The fair value of the technology and trade names acquired is estimated by management through a discounted cash flow model using the relief from royalty methodology, which involves the use of significant estimates and assumptions related to revenue growth rates, and discount rates.

Goodwill is evaluated for impairment when events or changes in circumstances indicate the fair value of a reporting unit with goodwill has been reduced below its carrying value, and otherwise at least annually. We have historically operated in two principal operating segments, Vinyls and Olefins. In the fourth quarter of 2021, we reorganized our business into two principal operating segments, Performance and Essential Materials and Housing and Infrastructure Products. As part of the reorganization, we assessed and re-defined reporting units effective as of the beginning of the fourth quarter of 2021, including reallocation of goodwill on a relative fair value basis as applicable to affected reporting units. Goodwill impairment analyses were performed as of the effective reorganization date both before and after the reorganization. We perform our annual impairment assessment for both the Performance and Essential Materials and Housing and Infrastructure Products reporting units in October each year. We may elect to perform an optional qualitative assessment to determine whether a quantitative impairment analysis is required. The qualitative assessment considers factors such as macroeconomic conditions, industry and market considerations, cost factors related to raw materials and labor, current and projected financial performance, changes in management or strategy, and market capitalization. Alternatively, we may unconditionally elect to bypass the qualitative assessment and perform a quantitative goodwill impairment assessment in any period.

We elected to perform the qualitative assessment for both of our segments' reporting units in the fourth quarter of 2022 and concluded that it is more likely than not that fair values of the reporting units exceed the carrying amounts and, as such, the quantitative impairment test was not required.

We performed the quantitative assessment for both of our segments' reporting units during the fourth quarter of 2021. The quantitative analysis compares a reporting unit's fair value to its carrying amount to determine whether goodwill is impaired. The fair values of the reporting units are calculated using both a discounted cash flow methodology and a market value methodology. The discounted cash flow projections are based on a forecast to reflect the cyclicality of the business. The forecast is based on historical results and estimates by management, including its strategic and operational plans, and financial performance of the market. The future cash flows are discounted to present value using an applicable discount rate. The significant assumptions used in determining the fair value of the reporting unit using the market value methodology include the determination of appropriate market comparables and the estimated multiples of EBITDA a willing buyer is likely to pay. Based on the quantitative tests performed during the fourth quarter of 2021, even if the fair values of the reporting units, excluding the reporting unit that is comprised of the business acquired in February 2022, decreased by 10% from the fair values determined for the quantitative tests, the carrying values of the reporting units would not have exceeded their fair values. See Item 1A, "Risk Factors—If our goodwill, indefinite-lived intangible assets or other intangible assets become impaired in the future, we may be required to record non-cash charges to earnings, which could be significant."

The results of operations of acquired businesses are included in our consolidated financial statements from the acquisition date.

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Long-Term Employee Benefit Costs. Our costs for long-term employee benefits, particularly pension and postretirement medical and life benefits, are incurred over long periods of time and involve many uncertainties over those periods. The net periodic benefit cost attributable to current periods is based on several assumptions about such future uncertainties and is sensitive to changes in those assumptions. It is our responsibility, often with the assistance of independent experts, to select assumptions that represent the best estimates of those uncertainties. It is also our responsibility to review those assumptions periodically and, if necessary, adjust the assumptions to reflect changes in economic or other factors.

Accounting for employee retirement plans involves estimating the cost of benefits that are to be provided in the future and attempting to match, for each employee, that estimated cost to the period worked. To accomplish this, we rely extensively on advice from actuaries, and we make assumptions about inflation, investment returns, mortality, employee turnover and discount rates that ultimately impact amounts recorded. Changes in these assumptions may result in different expense and liability amounts. One of the more significant assumptions relates to the discount rate for measuring benefit obligations. At December 31, 2022, the projected pension benefit obligations for U.S. and non-U.S. plans were calculated using assumed weighted average discount rates of 4.9% and 3.7%, respectively. The discount rates were determined using a benchmark pension discount curve and applying spot rates from the curve to each year of expected benefit payments to determine the appropriate discount rate. As a result of the funding relief provided by the enactment of the Bipartisan Budget Act of 2015, no minimum funding requirements are expected during 2023 for the U.S. pension plans. Additional information on the 2023 funding requirements and key assumptions underlying these benefit costs appear in Note 14 to the consolidated financial statements appearing elsewhere in this Form 10-K.

The following table reflects the sensitivity of the benefit obligation of our pension plans to changes in the actuarial assumptions:

A one-percentage point increase or decrease in assumed healthcare trend rates would not have a significant effect on the amounts reported for the healthcare plans.

While we believe that the amounts recorded in the consolidated financial statements appearing elsewhere in this Form 10-K related to these retirement plans are based on the best estimates and judgments available, the actual outcomes could differ from these estimates.

Income Taxes. We utilize the balance sheet method of accounting for deferred income taxes. Under this method, deferred tax assets or liabilities are recorded based upon temporary differences between the tax basis of assets and liabilities and their carrying values for financial reporting purposes. Deferred tax expense or benefit is the result of changes in the deferred tax assets and liabilities during the period. Valuation allowances are recorded against deferred tax assets when it is considered more likely than not that the deferred tax assets will not be realized. Additional information on income taxes appears in Note 17 to the consolidated financial statements appearing elsewhere in this Form 10-K.

Environmental and Legal Obligations. We consult with various professionals to assist us in making estimates relating to environmental costs and legal proceedings. We accrue an expense when we determine that it is probable that a liability has been incurred and the amount is reasonably estimable. While we believe that the amounts recorded in the accompanying consolidated financial statements related to these contingencies are based on the best estimates and judgments available, the actual outcomes could differ from our estimates. Additional information about certain legal proceedings and environmental matters appears in Note 22 to the consolidated financial statements appearing elsewhere in this Form 10-K.

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Asset Retirement Obligations. We recognize asset retirement obligations in the period in which the liability becomes probable and reasonably estimable. Initially, the asset retirement obligation is recorded at fair value and capitalized as a component of the carrying value of the long-lived asset to which the obligation relates. The liability is recorded at its future value each period, and the capitalized cost is depreciated over the estimated useful life of the related asset. Upon settlement of the liability, a gain or loss is recorded. We have conditional asset retirement obligations for the removal and disposal of hazardous materials from certain of our manufacturing facilities. Additional information on asset retirement obligations appears in Note 1, under Asset Retirement Obligations, to the consolidated financial statements appearing elsewhere in this Form 10-K.

We also have conditional asset retirement obligations that have not been recognized because the fair values of the conditional legal obligations cannot be measured due to the indeterminate settlement date of the obligations. Settlements of the unrecognized conditional asset retirement obligations are not expected to have a material adverse effect on our financial condition, results of operations or cash flows in any individual reporting period.

Recent Accounting Pronouncement

See Note 1 to the consolidated financial statements included in Item 8 of this Form 10-K for a full description of recent accounting pronouncement, including expected date of adoption and estimated effect on results of operations and financial condition.

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Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations

Overview

We are a vertically integrated global manufacturer and marketer of performance and essential materials and housing and infrastructure products. We have historically operated in two principal operating segments, Vinyls and Olefins. As a result of recent acquisitions, we reorganized our business into two principal operating segments, Performance and Essentials Materials and Housing and Infrastructure Products in the fourth quarter of 2021. Performance and Essential Materials segment includes Westlake North American Vinyls, Westlake North American Chlor-alkali & Derivatives, Westlake European & Asian Chlorovinyls, Westlake Olefins and Westlake Polyethylene. Housing and Infrastructure Products segment includes Westlake Royal Building Products, Westlake Pipe & Fittings, Westlake Global Compounds and Westlake Dimex. The change has been retrospectively reflected in the periods presented in this Form 10-K. We are highly integrated along our materials chain with significant downstream integration from ethylene and chlor-alkali (chlorine and caustic soda) into vinyls, polyethylene and styrene monomer. We also have substantial downstream integration from PVC into our building products, PVC pipes and fittings and PVC compounds in our Housing and Infrastructure Products segment.

Performance and Essentials Materials

Ethane-based ethylene producers have experienced a cost advantage over naphtha-based ethylene producers during periods of higher crude oil prices. This cost advantage has resulted in a strong export market for polyethylene and other ethylene derivatives and has benefited operating margins and cash flows for our Performance and Essential Materials segment during such periods. However, we have seen a significant reduction in the cost advantage enjoyed by North American ethane-based ethylene producers during periods of lower crude oil prices. In the past year, we have seen volatility in ethane and ethylene prices, primarily due to changes in demand resulting from the COVID-19 pandemic, anticipated timing for certain new ethylene capacity additions and availability of natural gas liquids. Additionally, we have seen volatility in ethane and ethylene prices in 2021 due to winter storm Uri and Hurricane Ida that resulted in shutdowns of many industry production facilities on the Gulf Coast and delayed or extended the timing of planned turnarounds of various ethylene crackers.

Our performance and essential materials such as ethylene, PVC, polyethylene and chlor-alkali are some of the most widely used materials in the world and are upgraded into a wide variety of higher value-added products used in many end-markets. Our performance and essential materials are used by customers in food and specialty packaging; industrial and consumer packaging; medical health applications; PVC pipe applications; consumer durables; mobility and transportation; and infrastructure products. Chlor-alkali and petrochemicals are typically manufactured in large volume by a number of different producers using widely available technologies. The chlor-alkali and petrochemical industries exhibit cyclical commodity characteristics, and margins are influenced by changes in the balance between supply and demand and the resulting operating rates, the level of general economic activity and the price of raw materials. Due to the significant size of new plants, capacity additions are built in large increments and typically require several years of demand growth to be absorbed. The cycle is generally characterized by periods of tight supply, leading to high operating rates and margins, followed by a decline in operating rates and margins primarily as a result of excess new capacity additions.

Westlake is the second-largest chlor-alkali producer and the second-largest PVC producer in the world. Demand for our products in the first half of 2020 was negatively impacted by the onset of the COVID-19 pandemic. Global demand for most of our products started strengthening in the second half of 2020 and remained strong throughout 2021, and we expect global demand for most of our products to remain robust in 2022. Depending on the performance of the global economy, potential changes in international trade and tariffs policies, the trend of crude oil prices, the timing of the new capacity additions in North America, Asia and the Middle East in 2022 and beyond, and the sustainability of the current, strong demand for most of our products, our financial condition, results of operations or cash flows could be negatively or positively impacted.

We purchase significant amounts of ethane feedstock, natural gas, ethylene and salt from external suppliers for use in production of performance and essential materials. We also purchase significant amounts of electricity to supply the energy required in our production processes. While we have agreements providing for the supply of ethane feedstock, natural gas, ethylene, salt and electricity, the contractual prices for these raw materials and energy vary with market conditions and may be highly volatile. Factors that have caused volatility in our raw material prices in the past, and which may do so in the future include:

•the availability of feedstock from shale gas and oil drilling;

•supply and demand for crude oil;

•shortages of raw materials due to increasing demand;

•ethane and liquefied natural gas exports;

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•capacity constraints due to higher construction costs for investments, construction delays, strike action or involuntary shutdowns;

•the general level of business and economic activity; and

•the direct or indirect effect of governmental regulation.

Significant volatility in raw material costs tends to put pressure on product margins as sales price increases could lag behind raw material cost increases. Conversely, when raw material costs decrease, customers may seek immediate relief in the form of lower sales prices. We currently use derivative instruments to reduce price volatility risk on feedstock commodities and lower overall costs. Normally, there is a pricing relationship between a commodity that we process and the feedstock from which it is derived. When this pricing relationship deviates from historical norms, we have from time to time entered into derivative instruments and physical positions in an attempt to take advantage of this relationship.

Our historical results have been significantly affected by our plant production capacity, our efficient use of that capacity and our ability to increase capacity. Since our inception, we have followed a disciplined growth strategy that focuses on plant acquisitions, new plant construction and internal expansion. We evaluate each expansion project on the basis of its ability to produce sustained returns in excess of our cost of capital and its ability to improve efficiency or reduce operating costs. We also regularly look at acquisition opportunities that would be consistent with, or complimentary to, our overall business strategies. Depending on the size of the acquisition, any such acquisitions could require external financing.

As noted above in Item 1A, "Risk Factors," we are subject to extensive environmental regulations, which may impose significant additional costs on our operations in the future. Further, concerns about GHG emissions and their possible effects on climate change has led to the enactment of regulations, and to proposed legislation and additional regulations, that could affect us in the form of increased cost of feedstocks and fuel, other increased costs of production and decreased demand for our products. While we do not expect any of these enactments or proposals to have a material adverse effect on us in the near term, we cannot predict the longer-term effect of any of these regulations or proposals on our future financial condition, results of operations or cash flows.

Housing and Infrastructure Products

Our Housing and Infrastructure Products segment is primarily comprised of building products, PVC pipes and fittings and PVC compound products. Our sales are affected by the individual decisions of distributors and dealers on the levels of inventory they carry, their views on product demand, their financial condition and the manner in which they choose to manage inventory risk. A significant portion of our performance in this segment is driven by the activities in the residential construction and repair and remodeling markets in North America. Performance of our housing and infrastructure products businesses over time are generally reflective of the trends of building permits and housing starts in the New Residential Construction Survey by the U.S. Census Bureau and Repair and Remodeling Index (RRI) provided by the National Association of Home Builders ("NAHB") among others. Looking ahead, we expect that the approval of the Infrastructure Investment and Jobs Act in November 2021 will have a favorable impact on certain industries related to our Housing and Infrastructure Products segment in the future.

The following table presents annual historical housing starts per the U.S. Census Bureau and the 2022 outlook per the NAHB:

North American PVC facilities within the Performance and Essential Materials segment supply most of the PVC required for our building products and PVC pipes and fittings plants. Our raw materials for stone, roofing and accessories, windows, shutters and specialty tool products are externally purchased. PVC required for the PVC compounds plants is either internally sourced from our North American and Asian facilities within the Performance and Essential Materials segment or externally purchased based on the location of the plants. The remaining feedstocks required, including pigments, fillers, stabilizers and other ingredients, are purchased under short-term contracts based on prevailing market prices.

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Factors that have caused volatility in our raw material prices and production processes in the past, and which may do so in the future include significant fluctuation in prices of these raw materials in response to, among other things, variable worldwide supply and demand across different industries, speculation in commodities futures, general economic or environmental conditions, labor costs, competition, import duties, tariffs, worldwide currency fluctuations, freight, regulatory costs, and product and process evolutions that impact demand for the same materials. Increasing raw material prices directly impact our cost of sales and our ability to maintain margins depends on implementing price increases in response to increasing raw material costs. The market for our products may or may not accept price increases, and as such, our future financial condition, results of operations or cash flows could be materially impacted.

Non-GAAP Financial Measures

The body of accounting principles generally accepted in the United States is commonly referred to as "GAAP." For this purpose, a non-GAAP financial measure is generally defined by the SEC as one that purports to measure historical or future financial performance, financial position or cash flows that (1) excludes amounts, or is subject to adjustments that have the effect of excluding amounts, that are included in the most directly comparable measure calculated and presented in accordance with GAAP in the statement of income, balance sheet or statement of cash flows (or equivalent statements) of the registrant; or (2) includes amounts, or is subject to adjustments that have the effect of including amounts, that are excluded from the most directly comparable measure so calculated and presented. In this report, we disclose non-GAAP financial measures, primarily earnings before interest, taxes, depreciation and amortization ("EBITDA"). We define EBITDA as net income before interest expense, income taxes, depreciation and amortization. The non-GAAP financial measures described in this Form 10-K are not substitutes for the GAAP measures of earnings and cash flows.

EBITDA is included in this Form 10-K because our management considers it an important supplemental measure of our performance and believes that it is frequently used by securities analysts, investors and other interested parties in the evaluation of companies in our industry, some of which present EBITDA when reporting their results. We regularly evaluate our performance as compared to other companies in our industry that have different financing and capital structures and/or tax rates by using EBITDA. In addition, we utilize EBITDA in evaluating acquisition targets. Management also believes that EBITDA is a useful tool for measuring our ability to meet our future debt service, capital expenditures and working capital requirements, and EBITDA is commonly used by us and our investors to measure our ability to service indebtedness. EBITDA is not a substitute for the GAAP measures of net income, income from operations and net cash provided by operating activities and is not necessarily a measure of our ability to fund our cash needs. In addition, it should be noted that companies calculate EBITDA differently and, therefore, EBITDA as presented for us may not be comparable to EBITDA reported by other companies. EBITDA has material limitations as a performance measure because it excludes interest expense, depreciation and amortization and income taxes. Reconciliations for EBITDA are included in the "Results of Operations" section below.

Significant Developments

COVID-19, Industry Conditions and Our Business

On March 11, 2020, the World Health Organization declared the ongoing COVID-19 outbreak a pandemic and recommended containment and mitigation measures worldwide. The pandemic has resulted in widespread adverse impacts on the global economy. We experienced significant disruptions in the second quarter of 2020 as the pandemic and its impact on the global economy spread through most of our markets. We were designated as an essential industry by many governments based on the nature of the products we manufacture. While demand for some of our products used in cleaning, packaging and medical applications and manufacturing continued to be firm, we expected lower demand for certain of our other products that led us to proactively temporarily idle production at several of our smaller non-integrated plants and reduce operating rates at others in the beginning of the second quarter of 2020. Since the middle of the second quarter of 2020, a general ease in government restrictions in many jurisdictions across the world has resulted in a gradual increase in demand for our products. As a result, all of our idled plants recommenced production. Except for the impact of the winter storm Uri and Hurricane Ida, operating rates have improved for most of our plants since the second half of 2020 due to continuing increase in demand for our products. Though the government restrictions across the world generally eased through the fourth quarter of 2021, there is considerable uncertainty regarding the extent to which COVID-19 will continue to spread and the extent and duration of governmental and other measures implemented to try to slow the spread of the virus. Factors that could impact the spread of COVID-19 include timing and logistics with respect to the distribution of vaccines globally, the efficacy of the available vaccines (including with respect to the more recent variants of COVID-19), vaccine hesitancy and the availability of other treatments. We continue to monitor the volatile environment and may reduce operating rates or idle production if the pandemic and its financial impacts persist or worsen. Considering the uncertain and volatile environment, we could continue to experience significant disruptions to our business operations in the near future.

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Acquisitions

Hexion Global Epoxy Business

On November 24, 2021, Westlake, through one of its wholly-owned subsidiaries, entered into a Stock Purchase Agreement (the "Hexion Purchase Agreement") by and among Hexion Inc. ("Hexion"), an Ohio corporation, and, solely for the limited purposes set forth therein, Westlake. Pursuant to the terms of the Hexion Purchase Agreement, Westlake agreed to acquire Hexion's global epoxy business for a purchase price of approximately $1,200 million in cash, subject to certain closing date adjustments as set forth in the Hexion Purchase Agreement. On February 1, 2022, we completed the acquisition of Hexion's global epoxy business (the "Hexion Acquisition"). The assets acquired and liabilities assumed and the results of operations of Hexion's epoxy business will be included in the Performance and Essential Materials segment. This acquisition represents a significant strategic expansion of Westlake's Performance and Essential Materials businesses into additional high-growth, innovative and sustainable-oriented applications – such as wind turbine blades and light-weight automotive structural components. Because epoxies are produced from chlorine and caustic soda, the transaction also provides vertical integration with our global chlor-alkali businesses.

Boral Target Companies

On June 20, 2021, Westlake, through one of its wholly-owned subsidiaries, entered into an Equity Purchase Agreement (the "Boral Purchase Agreement") by and among Boral Building Products Inc., a Michigan corporation, Boral Stone Products LLC, a Delaware limited liability company, Boral Lifetile Inc., a California corporation, Boral Windows LLC, a Utah limited liability company, Boral Industries Inc., a California corporation ("Boral Industries"), and, solely for the limited purposes set forth therein, Westlake and Boral Limited, an Australian corporation ("Boral"). Pursuant to the terms of the Boral Purchase Agreement, Westlake agreed to acquire from Boral Industries all of the issued and outstanding equity interests of certain subsidiaries of Boral Industries engaged in Boral's North American building products businesses in roofing, siding, trim and shutters, decorative stone and windows (the "Boral Target Companies"). On October 1, 2021, we completed the acquisition of the Boral Target Companies (the "Boral Acquisition"). The total closing purchase consideration was $2,132 million subject to working capital post-closing adjustments as well as a potential earn-out payment of up to $65 million if the windows division of the Boral Target Companies generates EBITDA in excess of a specified target in its fiscal year ending June 30, 2024. The assets acquired and liabilities assumed and the results of operations of this business are included in the Housing and Infrastructure Products segment.

Westlake Dimex Inc.

On August 2, 2021, Westlake, through one of its wholly-owned subsidiaries, entered into that certain Stock Purchase Agreement (the "Dimex Purchase Agreement") with DX Acquisition Corp., a Delaware corporation ("Dimex"), each of Dimex's stockholders, and for limited purposes, Westlake and Grey Mountain Partners Fund III Holdings, L.P., pursuant to which Westlake agreed to acquire Dimex. On September 10, 2021, we completed the acquisition of, and acquired all of the equity interests in, Dimex (the "Dimex Acquisition") and subsequently renamed the acquired company Westlake Dimex Inc. ("Westlake Dimex"). The total closing purchase consideration was $172 million, subject to working capital post-closing adjustments. The assets acquired and liabilities assumed and the results of operations of Westlake Dimex are included in the Housing and Infrastructure Products segment. Westlake Dimex is a producer of various consumer products made from post-industrial-recycled polyvinyl chloride, polyethylene and thermoplastic elastomer materials, including, landscape edging; home, office and industrial matting; marine dock edging; and masonry joint controls.

LASCO Fittings, Inc.

On July 4, 2021, Westlake, through one of its wholly-owned subsidiaries, entered into that certain Equity Purchase Agreement with Aalberts U.S. Holding Corp., a Delaware corporation ("Aalberts") and wholly-owned subsidiary of Aalberts N.V., pursuant to which Westlake agreed to acquire LASCO Fittings, Inc., a Delaware corporation ("LASCO"), from Aalberts. On August 19, 2021, we completed the acquisition of, and acquired all of the equity interests in, LASCO (the "LASCO Acquisition"). The total closing purchase consideration was $277 million. The assets acquired and liabilities assumed and the results of operations of LASCO are included in the Housing and Infrastructure Products segment. LASCO is a manufacturer of injected-molded PVC fittings that serve the plumbing, pool and spa, industrial, irrigation and retail markets in the United States.

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Senior Notes Offering

On August 19, 2021, we completed the registered public offering for $1,700 million aggregate principal amount of senior notes, comprised of $300 million aggregate principal amount of 0.875% senior notes due 2024 (the "0.875% 2024 Senior Notes"), $350 million aggregate principal amount of 2.875% senior notes due 2041 (the "2.875% 2041 Senior Notes"), $600 million aggregate principal amount of 3.125% senior notes due 2051 (the "3.125% 2051 Senior Notes") and $450 million aggregate principal amount of 3.375% senior unsecured notes due 2061 (the "3.375% 2061 Senior Notes" and, together with the 0.875% 2024 Senior Notes, the 2.875% 2041 Senior Notes and the 3.125% 2051 Senior Notes, the "Notes"). The net proceeds from the offering of the Notes were used to fund a portion of the purchase prices of the 2021 Acquisitions. See "Liquidity and Capital Resources—Debt" below and Note 11 to the consolidated financial statements included in this Form 10-K for more information.

Hurricane Ida

On August 29, 2021, Hurricane Ida made a landfall in Louisiana as a category 4 storm. Due to Hurricane Ida, several of our facilities in the region experienced disruption to their operations, resulting in lost production and sales and higher maintenance expense. Our facilities impacted by Hurricane Ida have resumed production.

Petro 2 Facility Flash Fire

In September 2021, OpCo's Petro 2 ethylene unit commenced turnaround activities. On September 27, 2021, shortly after the turnaround commenced, there was a flash fire at the quench tower of the Petro 2 facility. Several contractors working on the quench tower were injured. Although there was no sustained fire or offsite impact resulting from the incident and the quench tower did not sustain significant damage, due to the subsequent investigation by the Occupational Safety and Health Administration, the duration of the turnaround was extended and concluded in December 2021. There are lawsuits pending in connection with the flash fire at the quench tower.

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Results of Operations

Segment Data

The table below and descriptions that follow represent the consolidated results of operations of the Company for the years ended December 31, 2021, 2020 and 2019.

Net External Sales

The table below presents net external sales on a disaggregated basis for our two principal operating segments. Performance materials net external sales primarily consists of sales of PVC and polyethylene. Essential materials net external sales primarily consist of sales of caustic soda, styrene, and related derivative materials. Housing products net external sales primarily consist of sales of housing exterior and interior products, residential pipes and fittings and residential PVC compounds. Infrastructure products net external sales primarily consist of sales of non-residential pipes and fittings and non-residential PVC compounds.

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(1)See above for discussions on non-GAAP financial measures. See "Reconciliation of EBITDA to Net Income, Income from Operations and Net Cash Provided by Operating Activities" below.

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Housing Starts Data (14)

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(1)Industry pricing data was obtained through IHS Markit ("IHS"). We have not independently verified the data.

(2)Average Burner Tip contract prices of natural gas over the period.

(3)Average Mont Belvieu spot prices of purity ethane over the period.

(4)Average Mont Belvieu spot prices of non-TET propane over the period.

(5)Average North American spot prices of ethylene over the period.

(6)Average North American Net Transaction prices of polyethylene low density GP-Film grade over the period.

(7)Average North American contract prices of styrene over the period.

(8)Average USGC-CSLi index values for caustic soda over the period. As stated by IHS, "the caustic soda price listing represents the USGC-CSLi values. USGC-CSLi does not reflect contract price discounts, implementation lags, caps or other adjustments factors. Additionally, it is not intended to represent a simple arithmetic average of all market transactions occurring during the month. Rather, the USGC-CSLi is most representative of the month-to-month caustic soda price movement for contract volumes of liquid 50% caustic soda rather than the absolute value of contract prices at a particular point in time. It is intended to serve only as a benchmark."

(9)Average North American contract prices of chlorine over the period.

(10)Average North American contract prices of pipe grade PVC over the period. As stated by IHS, "the contract resin prices posted reflect an "index" or "market" for prices before discounts, rebates, incentives, etc."

(11)Average North American export price for low density polyethylene GP-Film grade over the period.

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(12)Average North American low spot export prices of caustic soda over the period.

(13)Average North American spot export prices of PVC over the period.

(14)Housing starts data per the U.S. Census Bureau.

Reconciliation of EBITDA to Net Income, Income from Operations and Net Cash Provided by Operating Activities

The following table presents the reconciliation of EBITDA to net income, income from operations and net cash provided by operating activities, the most directly comparable GAAP financial measures, for each of the periods indicated.