Beta

A measure of a stock's volatility relative to the overall market, with the market (typically the S&P 500) assigned a beta of 1.0. A stock with a beta of 1.5 is expected to move 50% more than the market in either direction, while a beta of 0.7 suggests less volatility. Utility stocks tend to have low betas; high-growth tech names typically run much higher. Beta is central to the Capital Asset Pricing Model (CAPM) developed by William Sharpe.