The Rate of Return
Return on investment (ROI) is a profitability measure used to evaluate the performance of investments, comparing the amount of return on an investment against the cost of the investment itself. Investment returns, when measuring performance, can be expressed as either relative returns or absolute returns. ROI calculations are essential to investors, who need to evaluate past investments and assess potential investments against concrete data.
Relative return
Relative return measures the rate of return in comparison to another security, benchmark or an index. Relative returns are usually reported in terms of ratios, such as the Sharpe ratio or the sortino ratio, to measure risk-adjusted return.
The Sharpe Ratio measures the excess return of an investment above the risk-free rate, relative to its overall risk. It is calculated as the return on a security minus the risk-free rate (usually the U.S. Treasury Bill return), divided by the standard deviation of the security’s returns.
The Sortino Ratio is similar to the Sharpe Ratio, but measures only the downside risk of the investment, rather than all risk. Its calculation is the excess return of the investment above the least acceptable return, divided by the downside deviation of the security’s returns.
Absolute return
Absolute return measures the rate of return of an investment in comparison to the initial capital outlay. Examples of absolute return metrics are internal rate of return and net present value.
Internal rate of return (IRR) is a metric used to measure returns by comparing the present value of a security’s future cash flows to its cost. It is also known as discounted cash flow (DCF) rate of return. The IRR calculation is made by discounting each cash flow to the present value, taking into account the cost of the investment, and solving for the rate that makes the net present value (NPV) of the security equal to zero.
Net present value is a metric used to compare the current value of a securitys expected cash flows to its cost. It is used to measure returns by calculating the present value of all cash flows, taking into account the cost of the investment and compound interest. NPV is calculated by adding the present values of all expected cash flows and subtracting the cost of the investment.
Conclusion
Return on investment (ROI) is a key metric used to measure the performance of investments in comparison to their cost. Relative returns, such as the Sharpe Ratio and the Sortino Ratio, use ratios to measure the return of an investment relative to another investment, benchmark or index. Absolute returns, such as the internal rate of return and net present value, compare the rate of return of a security to the initial outlay. Investors use these metrics to evaluate the past performance of an investment and forecast future returns.