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.

Alnylam Pharmaceuticals, Inc. (ALNY) had 20-Day Put-Call Ratio (Volume) of 0.5543 for 2026-04-21.

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

10-Day 20-Day 30-Day 60-Day
90-Day 120-Day 150-Day 180-Day

Figures for 2026-04-21

Volatility Metrics
Historical Volatility (Close-to-Close)	0.4231
Historical Volatility (Parkinson)	0.3550
Implied Volatility (Calls)	0.4755
Implied Volatility (Puts)	0.5448
Implied Volatility (Mean)	0.5101
Put-Call Implied Volatility Ratio	1.1459
Implied Volatility Skew	-0.0108
Option Statistics
Put-Call Ratio (Volume)	0.5543
Put-Call Ratio (Open Interest)	0.4156