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.

CarMax, Inc. (KMX) had 20-Day Historical Volatility (Parkinson) of 0.4156 for 2026-11-11.

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Figures for 2026-11-11

Volatility Metrics
Historical Volatility (Close-to-Close)	0.5006
Historical Volatility (Parkinson)	0.4156
Implied Volatility (Calls)	0.5609
Implied Volatility (Puts)	0.4868
Implied Volatility (Mean)	0.5238
Put-Call Implied Volatility Ratio	0.8678
Implied Volatility Skew	0.0441
Option Statistics
Put-Call Ratio (Volume)	12.4389
Put-Call Ratio (Open Interest)	1.5009