please calculate return on equity for 2018 using net income, preferred dividends and average commin stockholders equity.

1 Amazon Financial Statement Consolidated Statements Of Operations - USD ($) shares in Millions, $ in Millions 12 Months Ended Dec. 31, 2018 $ 232,887 Dec. 31, 2017 Dec 31, 2016 $177,866 $ 135,987 139,156 - 34,027 13,814 28,837 111,934 25,249 10,069 22,620 88,265 17,619 7,233 16,085 4 Total net sales 5 Operating expenses: 6 Cost of sales 7 Fulfillment 8 Marketing Expense Technology and content 9 10 General and administrative 11 Other operating expense, net 12 Total operating expenses 13 Operating Income (loss) 14 Interest income 15 Interest expense 16 Other Income (expense), net 17 Total non-operating income (expense) 18 Income before income taxes 19 Provision for income taxes 20 Equity.method Investment activity, net of tax 21 Net Income 22 Basic earnings per share 23 Diluted earnings per share 24 Weighted average shares used in computation of earnings per share: 25 Basic (in shares) 26 Diluted in shares) 27 Net product sales 28 Total net sales 29 Net service sales 4,336 296 220,466 12,421 440 (1,417) (183) (1,160) 11.261 (1.197) 3,674 214 173,760 4,106 202 (848) 346 (300) 3,806 (769) 2,432 167 131,801 4,186 100 (484) 90 (294) 3,892 (1,425) (96) S 2,371 $5.01 $ 4.90 $ 10,073 S 20.68 $ 20.14 $ 3,033 $ 6.32 $ 6.15 487 500 480 493 474 484 $ 141,915 $118.573 $ 94,665 Consolidated Balance Sheets - USD ($) $ in Millions Dec 31, 2018 Dec 31, 2017 Current assets: Cash and cash equivalents Marketable securities Inventories Accounts receivable, net and other Total current assets Property and equipment, net $ 31,750 9,500 17,174 16,677 75,101 61,797 $ 20,522 10,464 16,047 13,164 60,197 48,866 14,548 11,202 162.648 13,350 8,897 131,310 38,192 23,663 6,536 68,391 23,495 27,213 34,616 18,170 5,097 57,883 24,743 20,975 Goodwill Other assets Total assets Current liabilities: Accounts payable Accrued expenses and other Unearned revenue Total current liabilities Long-term debt Other long-term liabilities Commitments and contingencles (Note 7) Stockholders' equity: Preferred stock, $0.01 par value: Authorized shares - 500 Issued and outstanding shares - Common stock. $0.01 par value: Authorized shares - 5,000 Issued shares - 507 and 514 Treasury stock, at cost Additional paid-in capital Accumulated other comprehensive loss Retained earnings Total stockholders' equity Total liabilities and stockholders' equity (1,837) 26,791 (1,035) 19,625 43,549 $ 162,648 (1,837) 21,389 (484) 8,636 27.709 $ 131,310 Consolidated Statements of Cash Flows - USD ($) $ in Millions 12 Months Ended Dec 31, Dec. 31, Dec. 31, 2018 2017 2016 $ 21,856 ANNAN 10,073 3,033 2,371 15,341 11,478 8,116 5,418 274 219 441 4,215 202 (292) (29) 2,975 160 (20) (246) Statement of Cash Flows [Abstract] CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, BEGINNING OF PERIOD OPERATING ACTIVITIES: Net income Adjustments to reconcile net income to net cash from operating activities: Depreciation of property and equipment and other amortization, including capitalized content costs Stock-based compensation Other operating expense, net Other expense (income), net Deferred income taxes Changes in operating assets and liabilities: Inventories Accounts receivable, net and other Accounts payable Accrued expenses and other Unearned revenue Net cash provided by (used in) operating activities INVESTING ACTIVITIES: Purchases of property and equipment Proceeds from property and equipment Incentives Acquisitions, net of cash acquired, and other Sales and maturities of marketable securities Purchases of marketable securities Net cash provided by (used in) Investing activities FINANCING ACTIVITIES: Proceeds from long-term debt and other on Dating Ratio formulas (1,314) (3,583) (4,615) (4.780) 3,263 7,100 472 283 1.151 738 30,723 18,365 (1,426) (3.436) 5,030 1,724 1,955 17,203 (13,427) (11,955) 2,104 1,897 (2,186) (13,972) 8,240 9.677 (7.100) (12.731) (12,369) (27,084) (7,804) 1,067 (116) 4,577 (7.240) (9,516) 768 16,228 618 472 1,151 30,723 283 738 18,365 1,724 1,955 17,203 (13,427) (11,955) 2,104 1,897 (2,186) (13,972) 8,240 9,677 (7,100) (12,731) (12,369) (27,084) (7,804) 1,067 (116) 4,577 (7,240) (9,516) Accrued expenses and other Unearned revenue Net cash provided by (used in) operating activities INVESTING ACTIVITIES: Purchases of property and equipment Proceeds from property and equipment incentives Acquisitions, net of cash acquired, and other Sales and maturities of marketable securities Purchases of marketable securities Net cash provided by (used in) Investing activities FINANCING ACTIVITIES: Proceeds from long-term debt and other Repayments of long-term debt and other Principal repayments of capital lease obligations Principal repayments of finance lease obligations Net cash provided by (used in) financing activities Foreign currency effect on cash, cash equivalents, and restricted cash Net increase (decrease) in cash, cash equivalents, and restricted cash CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, END OF PERIOD SUPPLEMENTAL CASH FLOW INFORMATION: Cash paid for interest on long-term debt Cash paid for interest on capital and finance lease obligations Cash paid for Income taxes, net of refunds Property and equipment acquired under capital leases Property and equipment acquired under build to suit leases 768 (668) (7,449) (337) (7,686) (351) 10,317 32,173 16,228 (1,301) (4,799) (200) 9,928 713 1,922 21,856 618 (327) (3,860) (147) (3,716) (212) 3,759 19,934 206 854 328 290 575 319 1,184 957 10,615 9,637 5,704 $ 3,641 $3,541 $ 1,209 412