V-Lab
State Street SPDR Bloomberg 1-3 Month T-Bill ETF GJR-GARCH Volatility Analysis
Volatility prediction for Monday, July 27th, 2026
1 Day
0.32%
increased by 0.01%
1 Week
0.32%
increased by 0.01%
1 Month
0.32%
increased by 0.01%
Analysis last updated: Friday, July 24, 2026 at 10:12 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
May 30, 2007 to Jul 24, 2026Illiquid Asset
Model Insight
With persistence 0.994, volatility shocks have a half-life of 117 trading days (~0.5 years), close to a unit root, so long-run forecasts are highly sensitive to this estimate.
σ
GJR-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.0000 | |
α ARCH Response to squared shocks | 0.0212 | 13.81*** |
β GARCH Volatility persistence | 0.9737 | 264.52*** |
γ leverage Additional response to negative shocks | -0.0018 | -0.25 |
Persistence:
0.994
Half-life:
117 days
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