company's minimum desired rate of return for net present value analysis is 15%. Present Value of an Annuity of $1 at Compound Interest Compute the following: a. The average rate of return, giving effect to straight-line depreciation on the investment. If required, round your answer to one decimal place. % b. The cash payback period. company's minimum desired rate of return for net present value analysis is 15%. Present Value of an Annuity of $1 at Compound Interest Compute the following: a. The average rate of return, giving effect to straight-line depreciation on the investment. If required, round your answer to one decimal place. % b. The cash payback period