Put-Call Ratio (Volume) (20-Day)

Put-Call Ratio (Volume): The ratio of puts traded to calls traded, for options with the relevant expiration date.

Amphastar Pharmaceuticals, Inc. (AMPH) had 20-Day Put-Call Ratio (Volume) of 0.0180 for 2026-07-20.

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Figures for 2026-07-20

Volatility Metrics
Historical Volatility (Close-to-Close)	0.4174
Historical Volatility (Parkinson)	0.3818
Implied Volatility (Calls)	0.6704
Implied Volatility (Puts)	0.8833
Implied Volatility (Mean)	0.7768
Put-Call Implied Volatility Ratio	1.3175
Implied Volatility Skew	0.3303
Option Statistics
Put-Call Ratio (Volume)	0.0180
Put-Call Ratio (Open Interest)	0.2656