As part of her year-end responsibilities, Helen prepared the company's variable costing income statement as follows. Sales Variable expenses: $447,200 COGS $172,000 Operating expenses 17,200 189,200 Contribution margin 258,000 Fixed expenses: MOH 58,960 Operating expenses 79,000 137.960 Operating income $120,040 She hadn't been able to compare the income to last year's income yet, but she was expecting it to be lower because sales volume was down slightly from the prior year. Still, this year the company managed to produce 9,000 units, which was 200 units more than it had originally budgeted. Helen also included the following detail on her worksheet to support this income statement: variable operating expenses were $2 per unit, and there were no price or efficiency variances within the standard costing system this period