V-Lab
S&P 100 Index GARCH Volatility Analysis
Volatility prediction for Tuesday, September 8th, 2026
1 Day
11.78%
decreased by 0.18%
1 Week
12.00%
increased by 0.04%
1 Month
12.76%
increased by 0.80%
Analysis last updated: Friday, September 4, 2026 at 11:29 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 1, 1990 to Sep 4, 2026Model Insight
Volatility shocks decay with a half-life of 45 trading days, meaning a shock loses half its impact after approximately 45 days.
σ
GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.0190 | 5.25*** |
α ARCH Response to squared shocks | 0.0997 | 10.86*** |
β GARCH Volatility persistence | 0.8849 | 98.16*** |
Persistence:
0.985
Half-life:
45 days
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