Historical Volatility (Parkinson) (120-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.

Roundhill COST WeeklyPay ETF (COSW) had 120-Day Historical Volatility (Parkinson) of 0.1985 for 2026-05-21.

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Figures for 2026-05-21

Volatility Metrics
Historical Volatility (Close-to-Close)	0.2446
Historical Volatility (Parkinson)	0.1985
Implied Volatility (Calls)	0.1627
Implied Volatility (Puts)	0.4310
Implied Volatility (Mean)	0.2969
Put-Call Implied Volatility Ratio	2.6500
Implied Volatility Skew	--
Option Statistics
Put-Call Ratio (Volume)	--
Put-Call Ratio (Open Interest)	--