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.

Invesco S&P SmallCap Health Care ETF (PSCH) had 20-Day Put-Call Ratio (Open Interest) of 1.2727 for 2026-04-20.

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Figures for 2026-04-20

Volatility Metrics
Historical Volatility (Close-to-Close)	0.1771
Historical Volatility (Parkinson)	0.1442
Implied Volatility (Calls)	0.3115
Implied Volatility (Puts)	0.3287
Implied Volatility (Mean)	0.3201
Put-Call Implied Volatility Ratio	1.0553
Implied Volatility Skew	0.0247
Option Statistics
Put-Call Ratio (Volume)	--
Put-Call Ratio (Open Interest)	1.2727