Put-Call Ratio (Open Interest) (180-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 180-Day Put-Call Ratio (Open Interest) of 0.1151 for 2026-04-20.
For much more extensive volatility insights, check out our new product VolVue:
- Over 300 data fields encompassing historical volatility, implied volatility, and put-call ratios for multiple time frames
- Download data in CSV, Excel, JSON, or XML format
- Up to 20 years of data history
- 52-Week Rank and Percentile for all metrics and time frames