Historical Volatility (Parkinson) (30-Day)

Historical Volatility (Parkinson): The past volatility of the security over the selected time frame, calculated using the high and low prices on each trading day.

ProShares Ultra Technology (ROM) had 30-Day Historical Volatility (Parkinson) of 0.2829 for 2025-10-13.

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Figures for 2025-10-13

Volatility Metrics
Historical Volatility (Close-to-Close)	0.4403
Historical Volatility (Parkinson)	0.2829
Implied Volatility (Calls)	0.4804
Implied Volatility (Puts)	0.4982
Implied Volatility (Mean)	0.4893
Put-Call Implied Volatility Ratio	1.0372
Implied Volatility Skew	0.0661
Option Statistics
Put-Call Ratio (Volume)	0.0000
Put-Call Ratio (Open Interest)	0.2300