Historical Volatility (Parkinson) (180-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.
GCI Liberty, Inc. - Series C GCI Group (GLIBK) had 180-Day Historical Volatility (Parkinson) of 0.3577 for 2026-02-20.
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