The Profitability Index (PI) is a financial measure that is used to evaluate the expected return on investment (ROI) of a project or investment. It is calculated by dividing the present value of the expected cash flows from the project by the initial investment required to fund the project.The PI is a useful tool for comparing the relative attractiveness of different investment opportunities, as it takes into account the timing and size of the expected cash flows as well as the initial investment. A PI of greater than 1 indicates that the investment is expected to generate a positive return, while a PI of less than 1 indicates that the investment is expected to generate a negative return.The PI is often used in capital budgeting to help firms make informed decisions about which projects to invest in. It is generally considered to be a more comprehensive measure of ROI than other measures, such as the internal rate of return (IRR), as it takes into account the time value of money and the total expected cash flows from the project.It is important to note that the PI is based on estimates and projections, and is not a guarantee of future performance. As with any investment, there is always a risk that the actual return on investment may differ from the expected return.