On the Volatility Skew charts within the Volatility Dashboard, a Statistics Look Back Period control lets you choose between 30, 60, or 90 days of historical data.

What the shaded area represents

When a look back period is selected, the chart displays a shaded band overlaid on the current skew curve. This shaded area represents the 10th to 90th percentile range of implied volatility readings at each strike/delta/moneyness point over the chosen look back period.

• Upper edge of shading = 90th percentile IV over the look back period (historically elevated vol at that point)
• Lower edge of shading = 10th percentile IV over the look back period (historically suppressed vol at that point)
• Current skew curve vs. shading = shows whether today's implied volatility at each point is high, low, or in the middle of its recent historical range

How to use it

• If the current skew curve is above the shaded band, implied vol at those strikes is elevated relative to the lookback period — options are relatively expensive.
• If the current skew curve is below the shaded band, implied vol at those strikes is suppressed relative to history — options are relatively cheap.
• If the curve sits within the band, vol is in a normal historical range.

Choosing a look back period

• 30 days: tightest band, most sensitive to recent vol regime shifts
• 60 days: balanced view of recent and medium-term history
• 90 days: widest band, smoothed view across a fuller vol cycle

This feature is available on all three Volatility Skew views: Moneyness, Fixed Strike, and Delta.