Beta is a measure of a stock's volatility in relation to the market.

How should investors assess risk in the stocks they buy or sell? As you can imagine, the concept of risk is hard to pin down and factor into stock analysis and valuation. Is there a rating–some sort of number, letter, or phrase–that will do the trick?

One of the most popular indicators of risk is a statistical measure called beta. Stock analysts use this measure all the time to get a sense of stocks’ risk profiles. To learn about the basics of beta, take a look at Beta: Gauging Price Fluctuations. Here we shed some light on what the measure means for investors. While beta does say something about price risk, it does have its limits for investors looking for fundamental risk factors.

Beta
Beta is a measure of a stock’s volatility in relation to the market. By definition, the market has a beta of 1.0, and individual stocks are ranked according to how much they deviate from the market. A stock that swings more than the market over time has a beta above 1.0. If a stock moves less than the market, the stock’s beta is less than 1.0. High-beta stocks are supposed to be riskier but provide a potential for higher returns; low-beta stocks pose less risk but also lower returns.

Beta is a key component for the capital asset pricing model (CAPM), which is used to calculate cost of equity. Recall that the cost of capital represents the discount rate used to arrive at the present value of a company’s future cash flows. All things being equal, the higher a company’s beta is, the higher its cost of capital discount rate. The higher the discount rate, the lower the present value placed on the company’s future cash flows. In short, beta can impact a company’s share valuation.