The Boeing Company and Subsidiaries Consolidated Statements of Operations (Dollars in millions, except per share data) Years ended December 31, 2019, 2018 2017 Sales of products $66,094 $90,229 $83,740 Sales of services 10,465 10,898 10,265 Total revenues 76,559 101,127 94,005 Cost of products -62,877 -72,922 -68,879 Cost of services -9,154 -8,499 -7,663 Boeing Capital interest expense -62 -69 -70 Total costs and expenses -72,093 -81,490 -76,612 4,466 19,637 17,393 (Loss)/income from operating investments, net -4 111 204 General and administrative expense -3,909 -4,567 -4,095 Research and development expense, net -3,219 -3,269 -3,179 Gain on dispositions, net 691 75 21 (Loss)/earnings from operations -1,975 11,987 10,344 Other income, net 438 92 123 Interest and debt expense -722 -475 -360 (Loss)/earnings before income taxes -2,259 11,604 10,107 Income tax benefit/(expense) 1,623 -1,144 -1,649 Net (loss)/earnings -$636 $10,460 $8,458

calculate the contribution margin of the income statement