Consider a project that costs $100,000 and yields a return of $30,000 for five years. At the end of the fifth year, there is a cost of $20,000 to dispose of the waste from the project. Should the project be undertaken if the discount rate is 0? 10 percent? 15 percent? The interest rate at which the net present discounted value of the project is zero is referred to as the internal rate of return of the project.