Bloomberg US Credit Aa Total Return Index Value Unhedged USD GAS-GARCH Student T Volatility Analysis
Volatility prediction for Friday, July 17th, 2026
1 Day
4.33%
decreased by 0.15%
1 Week
4.33%
decreased by 0.15%
1 Month
4.33%
decreased by 0.15%
Analysis last updated: Friday, July 17, 2026 at 11:36 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Apr 23, 1996 to Nov 12, 2021Model Insight
With persistence 0.998, volatility shocks have a half-life of 339 trading days (~1.3 years), close to a unit root, so long-run forecasts are highly sensitive to this estimate. Returns follow a Student-t distribution with v = 6.63 degrees of freedom, capturing fatter tails than a normal distribution.
𝑓
GAS-GARCH-T Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.0755 | 7.13*** |
α ARCH Response to squared shocks | 0.0455 | 53.24*** |
β GARCH Volatility persistence | 0.9980 | 3,780.13*** |
ν DF Student-t tail thickness | 6.6274 | 12.43*** |
Persistence:
0.998
Half-life:
339 days
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