Standard deviation is a metric that shows the variability of a security’s returns over time. It can be used to gauge volatility based on past performance and compare a future return to past returns.

Learn about downside deviation, a crucial metric for assessing downside risk by focusing on returns below a minimum threshold, and how it influences investment strategies.

For a given data set, standard deviation measures how spread out the numbers are from an average value. This measurement of average variance has a prominent place in many fields related to statistics, ...