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.

Costco Wholesale Corporation (COST) had 20-Day Put-Call Ratio (Open Interest) of 0.9169 for 2025-05-14.

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Figures for 2025-05-14

Volatility Metrics
Historical Volatility (Close-to-Close)	0.1231
Historical Volatility (Parkinson)	0.1888
Implied Volatility (Calls)	0.3078
Implied Volatility (Puts)	0.3058
Implied Volatility (Mean)	0.3068
Put-Call Implied Volatility Ratio	0.9934
Implied Volatility Skew	0.0672
Option Statistics
Put-Call Ratio (Volume)	0.4747
Put-Call Ratio (Open Interest)	0.9169