Sharpe ratio

Using the Sharpe ratio is one way to compare the relationship of risk and reward in following different investment strategies, such as emphasizing growth or value investments, or in holding different combinations of investments.

To figure the ratio, the risk-free return is subtracted from the average return of an investment portfolio over a period of time, and the result is divided by the standard deviation of the return.

A strategy with a higher ratio is less risky than one with a lower ratio.

This type of analysis, which is done using sophisticated computer programs, is named for William P. Sharpe, who won the Nobel Prize in economics in 1990.