V-Lab
S&P GSCI Grains Spot Index GARCH Volatility Analysis
Volatility prediction for Friday, September 11th, 2026
1 Day
22.00%
increased by 0.08%
1 Week
22.00%
increased by 0.08%
1 Month
22.01%
increased by 0.09%
Analysis last updated: Thursday, September 10, 2026 at 11:03 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 2, 1990 to Sep 4, 2026Model Insight
With persistence 0.990, volatility shocks have a half-life of 71 trading days (~0.3 years), close to a unit root, so long-run forecasts are highly sensitive to this estimate.
σ
GARCH Model
Tap to view equation
High persistence: persistence 0.990, shock half-life ~71 days
| Param | Value | t-stat |
|---|---|---|
| ωconst | 0.0189 | 5.36*** |
| αARCH | 0.0583 | 10.74*** |
| βGARCH | 0.9320 | 154.04*** |
0.990
Persistence71d
Half-lifeσ
GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.0189 | 5.36*** |
α ARCH Response to squared shocks | 0.0583 | 10.74*** |
β GARCH Volatility persistence | 0.9320 | 154.04*** |
Persistence:
0.990
Half-life:
71 days
Other S&P GSCI Grains Spot Index Analyses
Other GARCH Analyses on Commodities