Historical Volatility (Close-to-Close) (20-Day)
Historical Volatility (Close-to-Close): The past volatility of the security over the selected time frame, calculated using the closing price on each trading day.
Amphastar Pharmaceuticals, Inc. (AMPH) had 20-Day Historical Volatility (Close-to-Close) of 0.3644 for 2025-05-30.
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