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.
Vanguard Russell 3000 Index Fund ETF Shares (VTHR) had 20-Day Historical Volatility (Parkinson) of 0.0769 for 2026-05-22.
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