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.

ONEOK, Inc. (OKE) had 20-Day Historical Volatility (Parkinson) of 0.3016 for 2026-04-06.

For much more extensive volatility insights, check out our new product VolVue:

Over 300 data fields encompassing historical volatility, implied volatility, and put-call ratios for multiple time frames
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Figures for 2026-04-06

Volatility Metrics
Historical Volatility (Close-to-Close)	0.2712
Historical Volatility (Parkinson)	0.3016
Implied Volatility (Calls)	0.3319
Implied Volatility (Puts)	0.3309
Implied Volatility (Mean)	0.3314
Put-Call Implied Volatility Ratio	0.9972
Implied Volatility Skew	0.0209
Option Statistics
Put-Call Ratio (Volume)	0.7194
Put-Call Ratio (Open Interest)	0.2413