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 0.1949 for 2026-08-03.

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Figures for 2026-08-03

Volatility Metrics
Historical Volatility (Close-to-Close)	0.3939
Historical Volatility (Parkinson)	0.4031
Implied Volatility (Calls)	0.3618
Implied Volatility (Puts)	0.3451
Implied Volatility (Mean)	0.3534
Put-Call Implied Volatility Ratio	0.9538
Implied Volatility Skew	0.0594
Option Statistics
Put-Call Ratio (Volume)	0.1949
Put-Call Ratio (Open Interest)	0.3271