Historical Volatility (Parkinson) (180-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.

Arq, Inc. (ARQ) had 180-Day Historical Volatility (Parkinson) of 0.5908 for 2026-10-20.

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Over 300 data fields encompassing historical volatility, implied volatility, and put-call ratios for multiple time frames
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Figures for 2026-10-20

Volatility Metrics
Historical Volatility (Close-to-Close)	0.5197
Historical Volatility (Parkinson)	0.5908
Implied Volatility (Calls)	--
Implied Volatility (Puts)	--
Implied Volatility (Mean)	--
Put-Call Implied Volatility Ratio	--
Implied Volatility Skew	--
Option Statistics
Put-Call Ratio (Volume)	1.1250
Put-Call Ratio (Open Interest)	0.0056