How much a fund or stock has tended to move relative to its benchmark; a beta of 1.2 suggests swings about 20% larger in either direction.
Beta describes sensitivity to the market. A beta of 1 means a fund has historically moved in line with its benchmark. Above 1, it has amplified market moves — rising more in rallies and falling more in declines. Below 1, it has moved less than the market. Beta is calculated from past returns, usually monthly returns over three years or more.
Why it matters
Beta helps you understand how a fund takes risk. Two equity funds might both have delivered 12% a year, one with a beta of 0.8 and the other with 1.3. The second is likely to feel far less comfortable in a falling market.
How to read it
- Beta measures only market-related (systematic) movement. It says nothing about risks specific to individual holdings.
- It is relative to a chosen benchmark. If the benchmark does not fit the fund’s style, the beta is less meaningful.
- It changes over time as the portfolio and markets change.
Common misconceptions
- “Low beta means low risk.” A low-beta fund can still lose money — through concentrated holdings, or credit events that have little to do with the wider market.
- “High beta means higher returns.” It means larger swings. Whether those swings were rewarded depends on the period.
- “Beta is fixed.” It is an average relationship from the past and can shift as the fund manager changes the portfolio.
In India: Equity scheme factsheets frequently publish beta against the scheme’s benchmark. Debt funds are usually described with duration and credit measures instead.
Formula
Beta = Covariance(Fund returns, Benchmark returns) ÷ Variance(Benchmark returns)
Worked example
For illustration, if a fund’s beta is 1.2 and its benchmark falls 10% in a month, the fund might be expected to fall around 12%; if the benchmark rises 10%, to rise around 12%. Actual moves will differ, because beta describes an average relationship, not a rule.
Figures are for illustration only — not a forecast or a recommendation.
Related terms
Alpha
The return a fund earned above or below what its benchmark or level of market risk would explain — a rough gauge of a manager’s value-add.
Standard deviation
A measure of how widely an investment’s returns have varied around their average; a higher figure means a bumpier ride.
Sharpe ratio
The return earned above a baseline, such as a Treasury bill yield, for each unit of volatility taken; higher means more return per unit of risk.
Benchmark
The index a fund’s performance is measured against, chosen to represent the market or segment the fund invests in.
Diversification
Spreading money across different investments so that a loss in any one of them has a limited effect on the whole portfolio.