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.

Catalyst Pharmaceuticals, Inc. (CPRX) had 20-Day Put-Call Ratio (Open Interest) of 0.2012 for 2026-04-21.

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Figures for 2026-04-21

Volatility Metrics
Historical Volatility (Close-to-Close)	0.2552
Historical Volatility (Parkinson)	0.2280
Implied Volatility (Calls)	0.5442
Implied Volatility (Puts)	--
Implied Volatility (Mean)	--
Put-Call Implied Volatility Ratio	--
Implied Volatility Skew	--
Option Statistics
Put-Call Ratio (Volume)	0.5000
Put-Call Ratio (Open Interest)	0.2012