A small company that specializes in powder coating expanded its building and purchased a new oven that is large enough to handle automobile frames. The building and oven cost $175,000, but new business from hot-rodders has increased annual income by $520,000. If operating expenses for gas, materials, labor, etc., amount to $470,000 per year, what rate of return will be made on the investment if only the cash flows that occur over the next 4 years are included in the calculation