Trading
Beta
A statistical measure of how a security has moved relative to a benchmark over a selected period.
What it means
Beta depends on the benchmark, return frequency, and time window used in the calculation. It describes past co-movement with the benchmark, not a fixed property of the company.
Example
A stock beta calculated against the S&P 500 can differ from a beta calculated against a sector index.
What not to infer
Beta does not guarantee future volatility or explain business fundamentals by itself.