Put-Call Ratio (Open Interest) (180-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.

NPK International Inc. (NPKI) had 180-Day Put-Call Ratio (Open Interest) of 0.0197 for 2026-01-16.

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Figures for 2026-01-16

Volatility Metrics
Historical Volatility (Close-to-Close)	0.3388
Historical Volatility (Parkinson)	0.3387
Implied Volatility (Calls)	0.5204
Implied Volatility (Puts)	0.5697
Implied Volatility (Mean)	0.5450
Put-Call Implied Volatility Ratio	1.0948
Implied Volatility Skew	0.0038
Option Statistics
Put-Call Ratio (Volume)	--
Put-Call Ratio (Open Interest)	0.0197