Use Additional Information from 10-K to Explain Linkages Among Financial Statements Community Health Systems operates general acute care hospitals in communities across the United States. The company reports the following information in Schedule II of its 2017 10-K. SCHEDULE II-VALUATION AND QUALIFYING ACCOUNTS Balance at Acquisitions Beginning and $ millions December 31, 2017, allowance for doubtful accounts December 31, 2016, allowance for doubtful accounts 4,110 3,504 Balance at End of Year Dispositions Expense Offs of Year $3,773 $(21) $3,054 $(2,936) $3,870 (365) 2,849 (2,821) 3,773 (17) 3,168 (2,545) 4,110 Bad Debt Write- December 31, 2015, allowance for doubtful accounts Accounts receivable represents the amount customers owe Community Health Systems for services rendered. The balance in the allowance for doubtful accounts is the company's best estimate of the amount that customers will not repay. Community Health Systems' balance sheet and income statement reported the following. $ millions Revenue 2017 2016 2015 $18,398 $21,275 $22,564 Operating income (loss) before tax (1,878) (860) 1,337 Total assets 17,450 21,944 26,861