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.

Alkermes plc (ALKS) had 20-Day Put-Call Ratio (Open Interest) of 0.8077 for 2026-04-21.

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Figures for 2026-04-21

Volatility Metrics
Historical Volatility (Close-to-Close)	0.4085
Historical Volatility (Parkinson)	0.3157
Implied Volatility (Calls)	0.5485
Implied Volatility (Puts)	0.5117
Implied Volatility (Mean)	0.5301
Put-Call Implied Volatility Ratio	0.9330
Implied Volatility Skew	0.0944
Option Statistics
Put-Call Ratio (Volume)	--
Put-Call Ratio (Open Interest)	0.8077