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.

Alcoa (AA) had 30-Day Historical Volatility (Parkinson) of 0.3614 for 2025-09-12.

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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 2025-09-12

Volatility Metrics
Historical Volatility (Close-to-Close)	0.4187
Historical Volatility (Parkinson)	0.3614
Implied Volatility (Calls)	0.4763
Implied Volatility (Puts)	0.4851
Implied Volatility (Mean)	0.4807
Put-Call Implied Volatility Ratio	1.0186
Implied Volatility Skew	0.0223
Option Statistics
Put-Call Ratio (Volume)	0.5446
Put-Call Ratio (Open Interest)	1.3960