DEFINITION
The realized volatility of a financial instrument over a given time period. Generally, this measure is calculated by determining the average deviation from the average price of a financial instrument in the given time period. Standard deviation is the most common but not the only way to calculate historical volatility.Also known as "statistical volatility."
INVESTOPEDIA EXPLAINS
This measure is frequently compared with implied volatility to determine if options prices are over or undervalued. Historical volatility is also used in all types of risk valuations. Stocks with a high historical volatility usually require a higher risk tolerance.RELATED TERMS

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