Historical Volatility (Parkinson) (30-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.

BlackLine (BL) had 30-Day Historical Volatility (Parkinson) of 0.2340 for 2025-08-01.

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Figures for 2025-08-01

Volatility Metrics
Historical Volatility (Close-to-Close)	0.2475
Historical Volatility (Parkinson)	0.2340
Implied Volatility (Calls)	0.5439
Implied Volatility (Puts)	0.5799
Implied Volatility (Mean)	0.5619
Put-Call Implied Volatility Ratio	1.0661
Implied Volatility Skew	0.1584
Option Statistics
Put-Call Ratio (Volume)	0.0091
Put-Call Ratio (Open Interest)	0.6863