S&P 500 Index GAS-GARCH Student T Volatility Analysis
Volatility prediction for Tuesday, April 21st, 2026
1 Day
16.83%
decreased by 1.04%
1 Week
16.86%
decreased by 1.01%
1 Month
16.99%
decreased by 0.88%
Analysis last updated: Tuesday, April 21, 2026 at 12:20 AM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
| param | t-stat | |
|---|---|---|
| 1.3760 | 5.52 | |
| 0.0861 | 40.94 | |
| 0.9909 | 558.90 | |
| 7.0250 | 7.71 |
Estimation Period:
Jan 1, 1990 to Apr 17, 2026
Jan 1, 1990 to Apr 17, 2026
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