Historical Volatility (Parkinson) (20-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.

Aramark (ARMK) had 20-Day Historical Volatility (Parkinson) of 0.2584 for 2026-01-20.

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Figures for 2026-01-20

Volatility Metrics
Historical Volatility (Close-to-Close)	0.2548
Historical Volatility (Parkinson)	0.2584
Implied Volatility (Calls)	0.3307
Implied Volatility (Puts)	0.3083
Implied Volatility (Mean)	0.3195
Put-Call Implied Volatility Ratio	0.9321
Implied Volatility Skew	--
Option Statistics
Put-Call Ratio (Volume)	0.0000
Put-Call Ratio (Open Interest)	0.0741