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.

ProShares K-1 Free Crude Oil ETF (OILK) had 30-Day Put-Call Ratio (Open Interest) of 0.4068 for 2026-04-21.

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Figures for 2026-04-21

Volatility Metrics
Historical Volatility (Close-to-Close)	0.4403
Historical Volatility (Parkinson)	0.2669
Implied Volatility (Calls)	0.6261
Implied Volatility (Puts)	0.7386
Implied Volatility (Mean)	0.6823
Put-Call Implied Volatility Ratio	1.1797
Implied Volatility Skew	-0.2009
Option Statistics
Put-Call Ratio (Volume)	0.1099
Put-Call Ratio (Open Interest)	0.4068