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 1.1597 for 2025-10-15.

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Figures for 2025-10-15

Volatility Metrics
Historical Volatility (Close-to-Close)	0.4958
Historical Volatility (Parkinson)	0.3491
Implied Volatility (Calls)	0.5065
Implied Volatility (Puts)	0.4961
Implied Volatility (Mean)	0.5013
Put-Call Implied Volatility Ratio	0.9796
Implied Volatility Skew	0.0339
Option Statistics
Put-Call Ratio (Volume)	1.1597
Put-Call Ratio (Open Interest)	2.0363