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.

Merck & Co., Inc. (MRK) had 30-Day Put-Call Ratio (Open Interest) of 0.6879 for 2026-05-22.

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Figures for 2026-05-22

Volatility Metrics
Historical Volatility (Close-to-Close)	0.2829
Historical Volatility (Parkinson)	0.2198
Implied Volatility (Calls)	0.3084
Implied Volatility (Puts)	0.2992
Implied Volatility (Mean)	0.3038
Put-Call Implied Volatility Ratio	0.9701
Implied Volatility Skew	0.0420
Option Statistics
Put-Call Ratio (Volume)	0.2144
Put-Call Ratio (Open Interest)	0.6879