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.

ATI Inc. (ATI) had 150-Day Historical Volatility (Parkinson) of 0.3425 for 2026-01-20.

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Figures for 2026-01-20

Volatility Metrics
Historical Volatility (Close-to-Close)	0.3588
Historical Volatility (Parkinson)	0.3425
Implied Volatility (Calls)	0.4666
Implied Volatility (Puts)	0.4685
Implied Volatility (Mean)	0.4675
Put-Call Implied Volatility Ratio	1.0042
Implied Volatility Skew	0.0275
Option Statistics
Put-Call Ratio (Volume)	0.0137
Put-Call Ratio (Open Interest)	0.1352