Difference- Increase or For the Year Ended December 31 Actual Planned (Decrease) Sales $1,926,100 $1,881,800 $44,300 Variable costs: Variable cost of goods sold $1,028,500 $989,400 $39,100 Variable selling and administrative expenses 205,700 232,800 (27,100) Total variable costs $1,234,200 $1,222,200 $12,000 Contribution margin $691,900 $659,600 $32,300 Number of units sold 18,700 19,400 Per unit: Sales price $103 $97 Variable cost of goods sold 55 51 Variable selling and administrative expenses 11 12 Prepare a contribution margin analysis of the variable costs for Romero Products Inc. for the year ended December 31. Romero Products Inc. Contribution Margin Analysis-Variable Costs For the Year Ended December 31 Effect of changes in variable costs of goods sold: Variable cost quantity factor Unit cost factor Total effect of change in variable cost of goods sold Effect of changes in variable selling and administrative expenses: Variable cost quantity factor Unit cost factor Total effect of changes in selling and administrative expenses Decrease in contribution margin from change in variable costs