1. Compute the common-size bad debt expense for each year. Note: Round percentage to one decimal point (for example, round 18.566% to 18.6%). 2017 2016 2015 Common size allowance % X % x % X across the United States. The SCHEDULE 11-VALUATION AND QUALIFYING ACCOUNTS Balance at Acquisitions Bad Balance Beginning and Debt Write- at End S millions of Year Dispositions Expense offs of Year December 31, 2017, allowance for doubtful accounts $3.735 $(21) $3,023 $(2.907) $3,830 December 31, 2016, allowance for doubtful accounts 4,069 (361) 2,821 (2.793) 3,736 December 31, 2015, allowance for doubtful accounts 3,469 (17) 3,136 (2.520) 4,068 Accounts receivable represents the amount customers owe Community Health Systems for services rendered. The that customers will not repay. Community Health Systems' balance sheet and income statement reported the follow S millions 2017 2016 2015 Revenue $18,398 $21,275 $22564 Operating income (loss) before tax (1,859) (851) 1,324 Total assets 17.450 21,944 26,861