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.

National HealthCare Corporation (NHC) had 30-Day Historical Volatility (Parkinson) of 0.2563 for 2025-05-30.

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Figures for 2025-05-30

Volatility Metrics
Historical Volatility (Close-to-Close)	0.3286
Historical Volatility (Parkinson)	0.2563
Implied Volatility (Calls)	0.2606
Implied Volatility (Puts)	0.2381
Implied Volatility (Mean)	0.2493
Put-Call Implied Volatility Ratio	0.9139
Implied Volatility Skew	--
Option Statistics
Put-Call Ratio (Volume)	--
Put-Call Ratio (Open Interest)	--