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.

iShares Biotechnology ETF (IBB) had 20-Day Put-Call Ratio (Open Interest) of 0.9527 for 2026-01-09.

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Figures for 2026-01-09

Volatility Metrics
Historical Volatility (Close-to-Close)	0.2419
Historical Volatility (Parkinson)	0.1897
Implied Volatility (Calls)	0.2444
Implied Volatility (Puts)	0.2190
Implied Volatility (Mean)	0.2317
Put-Call Implied Volatility Ratio	0.8961
Implied Volatility Skew	--
Option Statistics
Put-Call Ratio (Volume)	0.1888
Put-Call Ratio (Open Interest)	0.9527