Fiscal Year Ended December 31 2019 2018 2017 (in thousands) $2,004,719 $1,937,021 $1,835,987 4,649 4,406 4,811 2,406 2,324 2,203 $1,997,502 Gross sales Less: Sales discounts Less: Sales returns and allowances Net sales Cost of goods sold Gross profit Operating expenses Operating income Other income (expenses) Net income 621,463 $1,376,039 577,369 $1,930,048 $1,829,378 619,847 660,955 $1,310,201 $1,168,423 595,226 583,555 $798,670 $584,868 > $714,975 (6,060) 15,973 (8,773) $814,643 $708,915 $576,095 At December 31 2019 2017 2018 (in thousands) Accounts receivable $201,290 $195,427 $182,642 Less: Allowance for doubtful accounts 2,516 2,736 2,192 Net accounts receivable $198,774 $192,691 $180,450 Required: 1. Calculate the following ratios for 2018 and 2019. Round your answers to two decimal places. 2018 2019 % % % % M a. Gross profit margin b. Operating margin c. Net profit margin d. Accounts receivable turnover % % 2. Are operations improving or worsening