CompuWorld sells two products, R66 and R100, and calculates sales variances using the contribution margin. Pertinent data for the current year follow: Budgeted Actual R66 R100 R66 R100 Selling price $ 70 $ 200 $ 75 $ 195 Variable cost per unit 50 113 53 118 Contribution margin $ 20 $ 87 $ 22 $ 77 Fixed cost per unit 12 40 11 35 Operating income $ 8 $ 47 $ 11 $ 42 Sales in units 2,200 500 1,500 1,500 What is the total sales volume variance?