14. Reportable Segments: The Company has organized its business around four operating segments based on the review of discrete financial results for each of the operating segments by the Companys chief operating decision maker (the Companys President and Chief Executive Officer), or CODM, for performance assessment and resource allocation purposes. Each of the Companys operating segments represents a reportable segment under GAAP. The Companys reportable segments are organized based on the nature and economic characteristics of the Companys products. The Companys four reportable segments are as follows: (1) Refining Services provides sulfuric acid recycling to the North American refining industry; (2) Catalysts serves the packaging and engineered plastics and the global refining, petrochemical and emissions control industries; (3) Performance Materials produces transportation reflective safety markings for roads and airports; and (4) Performance Chemicals supplies diverse product end uses, including personal and industrial cleaning products, fuel-efficient tires, surface coatings, and food and beverage products. The Catalysts segment includes equity in net income from Zeolyst International and Zeolyst C.V. (collectively, the Zeolyst Joint Venture), each of which are 50/50 joint ventures with CRI Zeolites Inc. (a wholly-owned subsidiary of Royal Dutch Shell). The Zeolyst Joint Venture is accounted for using the equity method in the Companys consolidated financial statements (see Note 11 to these consolidated financial statements for further information). Company management evaluates the Catalysts segments performance, including the Zeolyst Joint Venture, on a proportionate consolidation basis. Accordingly, the revenues and expenses used to compute the Catalysts segments adjusted earnings before interest, income taxes, depreciation and amortization (Adjusted EBITDA) include the Zeolyst Joint Ventures results of operations on a proportionate basis based on the Companys 50% ownership level. Since the Company uses the equity method of accounting for the Zeolyst Joint Venture, these items are eliminated when reconciling to the Companys consolidated results of operations. The Companys management evaluates the operating results of each reportable segment based upon Adjusted EBITDA. Adjusted EBITDA consists of EBITDA, which is a measure defined as net income before interest, income taxes, depreciation and amortization (each of which is included in the Companys consolidated statements of income), and adjusted for certain items as discussed below. Summarized financial information for the Companys reportable segments is shown in the following table: Years ended December 31, 2019 2018 2017 Sales: Refining Services $ 447,081 $ 455,562 $ 398,342 Catalysts (1) 85,667 72,099 75,333 Performance Materials 362,965 378,279 324,225 Performance Chemicals 685,137 717,335 687,645 Eliminations (2) (13,778 ) (15,121 ) (13,444 ) Total $ 1,567,072 $ 1,608,154 $ 1,472,101 Segment Adjusted EBITDA: (3) Refining Services $ 175,640 $ 176,499 $ 154,191 Catalysts (4) 107,808 81,067 89,396 Performance Materials 76,712 72,471 69,661 Performance Chemicals 154,264 170,886 170,467 Total Segment Adjusted EBITDA (5) $ 514,424 $ 500,923 $ 483,715 (1) Excludes the Companys proportionate share of sales from the Zeolyst Joint Venture accounted for using the equity method. The proportionate share of sales is $170,338 , $156,687 and $143,774 for the years ended December 31, 2019 , 2018 and 2017 , respectively. (2) The Company eliminates intersegment sales when reconciling to the Companys consolidated statements of income. (3) The Company defines Adjusted EBITDA as EBITDA adjusted for certain items as noted in the reconciliation below. Management evaluates the performance of its segments and allocates resources based on several factors, of which the primary measure is Adjusted EBITDA. Adjusted EBITDA should not be considered as an alternative to net income as an indicator of the Companys operating performance. Adjusted EBITDA as defined by the Company may not be comparable with EBITDA or Adjusted EBITDA as defined by other companies. (4) The Adjusted EBITDA from the Zeolyst Joint Venture included in the Catalysts segment is $68,138 for the year ended December 31, 2019 , which includes $45,899 of equity in net income plus $7,534 of amortization of investment in affiliate step-up plus $14,705 of joint venture depreciation, amortization and interest. The Adjusted EBITDA from the Zeolyst Joint Venture included in the Catalysts segment is $56,663 for the year ended December 31, 2018 , which includes $37,437 of equity in net income plus $6,634 of amortization of investment in affiliate step-up plus $12,592 of joint venture depreciation, amortization and interest. The Adjusted EBITDA from the Zeolyst Joint Venture included in the Catalysts segment is $58,156 for the year ended December 31, 2017 , which includes $38,486 of equity in net income plus $8,600 of amortization of investment in affiliate step-up plus $11,070 of joint venture depreciation, amortization and interest. (5) Total Segment Adjusted EBITDA differs from the Companys consolidated Adjusted EBITDA due to unallocated corporate expenses. A reconciliation of net income attributable to PQ Group Holdings to Segment Adjusted EBITDA is as follows: Years ended December 31, 2019 2018 2017 Reconciliation of net income attributable to PQ Group Holdings Inc. to Segment Adjusted EBITDA Net income attributable to PQ Group Holdings Inc. $ 79,539 $ 58,300 $ 57,603 Provision for (benefit from) income taxes 40,699 28,995 (119,197 ) Interest expense, net 111,525 113,723 179,044 Depreciation and amortization 182,090 185,234 177,140 Segment EBITDA 413,853 386,252 294,590 Unallocated corporate expenses 40,070 36,970 30,422 Joint venture depreciation, amortization and interest 14,705 12,592 11,070 Amortization of investment in affiliate step-up 7,534 6,634 8,600 Amortization of inventory step-up  1,603 871 Impairment of fixed assets, intangibles and goodwill 1,600   Debt extinguishment costs 3,400 7,751 61,886 Net (gain) loss on asset disposals (13,068 ) 6,574 5,793 Foreign currency exchange loss 2,787 13,810 25,786 LIFO expense 11,099 8,366 3,708 Management advisory fees   3,777 Transaction and other related costs 3,642 893 7,425 Equity-based compensation 18,225 19,464 8,799 Restructuring, integration and business optimization expenses 4,076 14,019 13,174 Defined benefit pension plan cost 3,126 (796 ) 2,940 Gain on contract termination (1)  (20,612 )  Other 3,375 7,403 4,874 Segment Adjusted EBITDA $ 514,424 $ 500,923 $ 483,715 (1) Includes the non-cash write-off of a long-term supply contract obligation (see Note 26 ), which was recorded as a reduction in other operating expense, net in the consolidated statement of income for the year ended December 31, 2018. The Companys consolidated results include equity in net income from affiliated companies of $46,034 , $37,611 and $38,772 for the years ended December 31, 2019 , 2018 , and 2017 , respectively. This is primarily comprised of equity in net income of $45,899 , $37,437 and $38,486 in the Catalysts segment from the Zeolyst Joint Venture for the years ended December 31, 2019 , 2018 and 2017 , respectively. The remaining equity in net income for the Company is included in the Performance Chemicals and Performance Materials segments, which was attributed to smaller investments and was not material. The Companys equity in net income from affiliated companies in the consolidated results includes amortization expense related to purchase accounting fair value adjustments associated with the Zeolyst Joint Venture as a result of a prior business combination. Capital expenditures for the Companys reportable segments are shown in the following table: Years ended December 31, 2019 2018 2017 Capital expenditures: Refining Services $ 42,310 $ 46,617 $ 42,876 Catalysts (1) 8,984 8,390 10,269 Performance Materials 16,074 18,001 20,394 Performance Chemicals 54,683 57,475 64,389 Corporate (2) 5,591 1,205 2,554 Capital expenditures per the consolidated statements of cash flows $ 127,642 $ 131,688 $ 140,482 (1) Excludes the Companys proportionate share of capital expenditures from the Zeolyst Joint Venture. (2) Includes corporate capital expenditures, the cash impact from changes in capital expenditures in accounts payable and capitalized interest. Total assets by segment are not disclosed by the Company because the information is not prepared or used by the CODM to assess performance and to allocate resources. Sales and long-lived assets by geographic area are presented in the following tables. Sales are attributed to countries based upon location of products shipped. Years ended December 31, 2019 2018 2017 Sales (1) : United States $ 953,511 $ 963,722 $ 874,764 Netherlands 117,211 127,803 118,567 United Kingdom 118,626 119,586 116,410 Other foreign countries 377,724 397,043 362,360 Total $ 1,567,072 $ 1,608,154 $ 1,472,101 (1) Except for the United States, no sales in an individual country exceeded 10% of the Companys total sales. December 31, 2019 2018 Long-lived assets (1) : United States $ 834,229 $ 865,799 Netherlands 49,559 52,461 United Kingdom 97,426 90,095 Other foreign countries 205,556 200,624 Total $ 1,186,770 $ 1,208,979 (1) Long-lived assets include property, plant and equipment, net.