Put-Call Ratio (Open Interest) (30-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 30-Day Put-Call Ratio (Open Interest) of 0.0444 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)	0.3068
Implied Volatility (Calls)	0.6796
Implied Volatility (Puts)	0.5614
Implied Volatility (Mean)	0.6205
Put-Call Implied Volatility Ratio	0.8261
Implied Volatility Skew	-0.1673
Option Statistics
Put-Call Ratio (Volume)	--
Put-Call Ratio (Open Interest)	0.0444