Historical Volatility (Parkinson) (20-Day)
Historical Volatility (Parkinson): The past volatility of the security over the selected time frame, calculated using the high and low prices on each trading day.
iShares Defense Industrials and Tech Active ETF (IDEF) had 20-Day Historical Volatility (Parkinson) of 0.1357 for 2026-10-16.
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