Historical Volatility (Parkinson) (90-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.

American Century Large Cap Equity ETF (ACLC) had 90-Day Historical Volatility (Parkinson) of 0.0767 for 2026-01-20.

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Figures for 2026-01-20

Volatility Metrics
Historical Volatility (Close-to-Close)	0.1284
Historical Volatility (Parkinson)	0.0767
Implied Volatility (Calls)	--
Implied Volatility (Puts)	--
Implied Volatility (Mean)	--
Put-Call Implied Volatility Ratio	--
Implied Volatility Skew	--
Option Statistics
Put-Call Ratio (Volume)	--
Put-Call Ratio (Open Interest)	--