What is the correct definition of Internal Rate of Return (IRR)?

Internal Rate of Return (IRR) is defined as the discount rate that makes the net present value (NPV) of a series of cash flows equal to zero. In essence, it represents the expected rate of return on an investment, taking into account the time value of money. When using IRR, the objective is to find that specific rate at which the present value of cash inflows equals the present value of cash outflows over the duration of the investment. Thus, it provides a useful metric for evaluating the profitability of potential investments or projects.

By identifying the discount rate that results in an NPV of zero, IRR allows investors to compare the profitability of various investments directly. If the IRR is greater than the required rate of return or the cost of capital, the investment is generally considered a good choice.

The other definitions do not accurately encapsulate the specifics of IRR. While the expected return on investment, the average rate of return, and a market-determined fixed rate may relate to investment assessments, they do not represent the precise mathematical calculation and significance of the IRR in financial analysis.