Historical Volatility (Parkinson) (30-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.

Alector, Inc. (ALEC) had 30-Day Historical Volatility (Parkinson) of 1.2244 for 2026-09-03.

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Figures for 2026-09-03

Volatility Metrics
Historical Volatility (Close-to-Close)	1.3022
Historical Volatility (Parkinson)	1.2244
Implied Volatility (Calls)	--
Implied Volatility (Puts)	--
Implied Volatility (Mean)	--
Put-Call Implied Volatility Ratio	--
Implied Volatility Skew	--
Option Statistics
Put-Call Ratio (Volume)	20.6865
Put-Call Ratio (Open Interest)	2.8896