Historical Volatility (Parkinson) (150-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 150-Day Historical Volatility (Parkinson) of 0.3933 for 2025-12-16.

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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 2025-12-16

Volatility Metrics
Historical Volatility (Close-to-Close)	0.5069
Historical Volatility (Parkinson)	0.3933
Implied Volatility (Calls)	0.4966
Implied Volatility (Puts)	0.4845
Implied Volatility (Mean)	0.4906
Put-Call Implied Volatility Ratio	0.9756
Implied Volatility Skew	0.0196
Option Statistics
Put-Call Ratio (Volume)	0.7227
Put-Call Ratio (Open Interest)	1.0312