Direct materials inventory, January 1 $2,550 Direct materials inventory, December 31 2,920 Work-in-process inventory, January 1 2,750 Work-in-process inventory, December 31 3,900 Finished goods inventory, January 1 1,920 Finished goods inventory, December 31 400 Purchases of direct materials 16,280 Cost of goods manufactured during the year 53,720 Total manufacturing costs Cost of goods sold 55,240 Gross margin 48,110 Direct labor Direct materials used 14,780 Manufacturing overhead 13,710 Sales revenue