Put-Call Ratio (Open Interest) (30-Day)
Put-Call Ratio (Open Interest): The ratio of outstanding put contracts to outstanding call contracts at the close of the trading day, for options with the relevant expiration date.
Amphastar Pharmaceuticals, Inc. (AMPH) had 30-Day Put-Call Ratio (Open Interest) of 0.6554 for 2025-10-13.
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