NOTES TO CONSOLIDATED FINANCIAL STATEMENTS OF AMERICAN AIRLINES, INC. As of December 31, 2019, there was $108 million of unrecognized compensation cost related to RSUs. These costs are expected to be recognized over a weighted average period of one year. The total fair value of RSUs vested during the years ended December 31, 2019, 2018 and 2017 was $68 million, $91 million and $123 million, respectively. Unaudited summarized financial data by quarter for 2019 and 2018 (in millions): American’s fourth quarter 2019 results include $108 million of total pre-tax net special items that principally included $85 million of merger integration expenses and $39 million of fleet restructuring expenses, offset in part by $42 million of mark-to-market net unrealized gains associated with certain equity and other investments. American’s fourth quarter 2018 results include $190 million of total pre-tax net special items that principally included $94 million of fleet restructuring expenses, $81 million of merger integration expenses, $37 million of severance costs associated with reductions of management and support staff team members, $22 million of mark-to-market net unrealized losses associated with certain equity investments, offset in part by a $37 million net credit resulting from mark-to-market adjustments on bankruptcy obligations. 156 15. Quarterly Financial Data (Unaudited) 14. Valuation and Qualifying Accounts (in millions) First Quarter Second Quarter Third Quarter Fourth Quarter 2019 Operating revenues $ 10,581 $ 11,958 $ 11,910 $ 11,312 Operating expenses 10,236 10,831 11,082 10,565 Operating income 345 1,127 828 747 Net income 230 714 508 520 2018 Operating revenues $ 10,398 $ 11,640 $ 11,556 $ 10,936 Operating expenses 9,986 10,626 10,850 10,344 Operating income 412 1,014 706 592 Net income 209 609 433 407 Balance at Beginning of Year Additions Charged to Statement of Operations Accounts Deductions Balance at End of Year Allowance for obsolescence of spare parts Year ended December 31, 2019 $ 754 $ 79 $ (104) $ 729 Year ended December 31, 2018 717 57 (20 ) 754 Year ended December 31, 2017 720 18 (21) 717 Allowance for uncollectible accounts Year ended December 31, 2019 $ 24 $ 17 $ (16) $ 25 Year ended December 31, 2018 21 39 (36 ) 24 Year ended December 31, 2017 35 41 (55) 21