Historical Volatility (Parkinson) (90-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.

TransUnion (TRU) had 90-Day Historical Volatility (Parkinson) of 0.3895 for 2026-10-19.

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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 2026-10-19

Volatility Metrics
Historical Volatility (Close-to-Close)	0.4365
Historical Volatility (Parkinson)	0.3895
Implied Volatility (Calls)	0.4667
Implied Volatility (Puts)	0.4657
Implied Volatility (Mean)	0.4662
Put-Call Implied Volatility Ratio	0.9979
Implied Volatility Skew	0.0321
Option Statistics
Put-Call Ratio (Volume)	0.0159
Put-Call Ratio (Open Interest)	0.3761