Implied Volatility Skew (20-Day)

Implied Volatility Skew: A measurement that quantifies the difference in implied volatility of options at lower and higher strike prices.

ProShares Ultra Nasdaq Biotechnology (BIB) had 20-Day Implied Volatility Skew of 0.0435 for 2026-07-21.

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 2026-07-21

Volatility Metrics
Historical Volatility (Close-to-Close)	0.4777
Historical Volatility (Parkinson)	0.3542
Implied Volatility (Calls)	0.4278
Implied Volatility (Puts)	0.4310
Implied Volatility (Mean)	0.4294
Put-Call Implied Volatility Ratio	1.0074
Implied Volatility Skew	0.0435
Option Statistics
Put-Call Ratio (Volume)	13.0000
Put-Call Ratio (Open Interest)	0.8571