associate
24 Points
Joined February 2008
The Internal Rate of Return (IRR) is the discount rate that generates a zero net present value for a series of future cash flows. This essentially means that IRR is the rate of return that makes the sum of present value of future cash flows and the final market value of a project (or an investment) equal its current market value.
Internal Rate of Return provides a simple ‘hurdle rate’, whereby any project should be avoided if the cost of capital exceeds this rate. Usually a financial calculator has to be used to calculate this IRR, though it can also be mathematically calculated using the following formula:

In the above formula, CF is the Cash Flow generated in the specific period (the last period being ‘n’). IRR, denoted by ‘r’ is to be calculated by employing trial and error method.
Internal Rate of Return is the flip side of Net Present Value (NPV), where NPV is the discounted value of a stream of cash flows, generated from an investment. IRR thus computes the break-even rate of return showing the discount rate, below which an investment results in a positive NPV.
A simple decision-making criteria can be stated to accept a project if its Internal Rate of Return exceeds the cost of capital and rejected if this IRR is less than the cost of capital. However, it should be kept in mind that the use of IRR may result in a number of complexities such as a project with multiple IRRs or no IRR. Moreover, IRR neglects the size of the project and assumes that cash flows are reinvested at a constant rate.