CAC 40 Index Spline-GARCH Volatility Analysis
Volatility prediction for Monday, July 20th, 2026
1 Day
12.92%
decreased by 0.31%
1 Week
13.23%
increased by 0.00%
1 Month
14.23%
increased by 1.00%
Analysis last updated: Friday, July 17, 2026 at 04:03 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 2, 1990 to Jul 17, 2026Model Insight
This model fits a time-varying baseline (a spline), so volatility mean-reverts toward a slowly-shifting long-run level rather than a constant. Short-run deviations decay with a half-life of 30 trading days.
τ
Spline-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 1.1216 | 7.84*** |
α ARCH Response to squared shocks | 0.1004 | 10.52*** |
β GARCH Volatility persistence | 0.8764 | 80.35*** |
Spline Coefficients
K=1
| γ1 | 0.0001 | 0.18 |
Persistence:
0.977
Half-life:
30 days
Other CAC 40 Index Analyses
Other Spline-GARCH Analyses on Equity Indices