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.

Biogen Inc. (BIIB) had 20-Day Put-Call Ratio (Volume) of 6.4621 for 2026-04-29.

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Figures for 2026-04-29

Volatility Metrics
Historical Volatility (Close-to-Close)	0.3840
Historical Volatility (Parkinson)	0.3177
Implied Volatility (Calls)	0.3358
Implied Volatility (Puts)	0.3334
Implied Volatility (Mean)	0.3346
Put-Call Implied Volatility Ratio	0.9929
Implied Volatility Skew	0.0335
Option Statistics
Put-Call Ratio (Volume)	6.4621
Put-Call Ratio (Open Interest)	1.3613