Put-Call Ratio (Open Interest) (20-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 20-Day Put-Call Ratio (Open Interest) of 0.2454 for 2026-06-22.

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Figures for 2026-06-22

Volatility Metrics
Historical Volatility (Close-to-Close)	0.3176
Historical Volatility (Parkinson)	0.3127
Implied Volatility (Calls)	0.3136
Implied Volatility (Puts)	0.3741
Implied Volatility (Mean)	0.3439
Put-Call Implied Volatility Ratio	1.1929
Implied Volatility Skew	--
Option Statistics
Put-Call Ratio (Volume)	0.3225
Put-Call Ratio (Open Interest)	0.2454