Put-Call Ratio (Volume) (20-Day)

Put-Call Ratio (Volume): The ratio of puts traded to calls traded, for options with the relevant expiration date.

Alector, Inc. (ALEC) had 20-Day Put-Call Ratio (Volume) of 0.0135 for 2026-03-06.

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Figures for 2026-03-06

Volatility Metrics
Historical Volatility (Close-to-Close)	0.8900
Historical Volatility (Parkinson)	0.9472
Implied Volatility (Calls)	3.0733
Implied Volatility (Puts)	2.7486
Implied Volatility (Mean)	2.9110
Put-Call Implied Volatility Ratio	0.8943
Implied Volatility Skew	--
Option Statistics
Put-Call Ratio (Volume)	0.0135
Put-Call Ratio (Open Interest)	0.0120