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.

Vanguard S&P Mid-Cap 400 ETF (IVOO) had 30-Day Put-Call Ratio (Open Interest) of 0.1077 for 2025-05-30.

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Figures for 2025-05-30

Volatility Metrics
Historical Volatility (Close-to-Close)	0.2095
Historical Volatility (Parkinson)	0.1181
Implied Volatility (Calls)	0.2058
Implied Volatility (Puts)	0.2161
Implied Volatility (Mean)	0.2109
Put-Call Implied Volatility Ratio	1.0501
Implied Volatility Skew	0.1328
Option Statistics
Put-Call Ratio (Volume)	--
Put-Call Ratio (Open Interest)	0.1077