Any help as to how I can go about determining what last years margin is ?

Westerville Company reported the following results from last year's operations: Sales $ 1,600,000 Variable expenses 700,000 Contribution margin 900,000 Fixed expenses 660,000 Net operating income 5 240,000 Average operating assets $ 1,000,000 [ At the beginning of this year, the company has a $325,000 investment opportunity with the following cost and revenue characteristics: Sales $ 520,000 Contribution margin ratio 70 % of sales Fixed expenses $ 312,000 The company's minimum required rate of return is 15%. Foundational 11-1 Required: 1. What is last year's margin