Put-Call Ratio (Open Interest) (180-Day)

Put-Call Ratio (Open Interest): The ratio of outstanding put contracts to outstanding call contracts at the close of the trading day, for options with the relevant expiration date.

Biogen Inc. (BIIB) had 180-Day Put-Call Ratio (Open Interest) of 0.3527 for 2025-09-15.

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Figures for 2025-09-15

Volatility Metrics
Historical Volatility (Close-to-Close)	0.3484
Historical Volatility (Parkinson)	0.3190
Implied Volatility (Calls)	0.3610
Implied Volatility (Puts)	0.3533
Implied Volatility (Mean)	0.3572
Put-Call Implied Volatility Ratio	0.9788
Implied Volatility Skew	0.0271
Option Statistics
Put-Call Ratio (Volume)	0.3446
Put-Call Ratio (Open Interest)	0.3527