How can risk of a security be calculated?

The risk of a security can be calculated using various methods, with one common approach being the Capital Asset Pricing Model (CAPM), which assesses the expected return of an asset based on its systematic risk (beta) relative to the overall market. Another method involves calculating the historical volatility of the security's price, which provides insight into its past price fluctuations. Additionally, one can use metrics like Value at Risk (VaR) to estimate the potential loss in value over a defined period, given normal market conditions. Ultimately, combining these quantitative measures with qualitative factors, such as market trends and company performance, can provide a comprehensive risk assessment.