V-Lab
S&P GSCI Zinc Index Zero Slope Spline-GARCH Volatility Analysis
Volatility prediction for Monday, September 21st, 2026
1 Day
23.28%
decreased by 0.13%
1 Week
23.31%
decreased by 0.10%
1 Month
23.43%
increased by 0.02%
Analysis last updated: Saturday, September 19, 2026 at 12:03 AM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 7, 1991 to Sep 18, 2026Model Insight
With persistence 0.996, volatility shocks have a half-life of 172 trading days (~0.7 years), close to a unit root, so long-run forecasts are highly sensitive to this estimate.
τ
Zero Slope Spline-GARCH Model
Tap to view equation
High persistence: persistence 0.996, shock half-life ~172 days
| Param | Value | t-stat |
|---|---|---|
| ωconst | 0.9367 | 4.64*** |
| αARCH | 0.0323 | 4.92*** |
| βGARCH | 0.9637 | 135.92*** |
Spline Coefficients
K=1
| γ1 | -0.0001 | -0.35 |
0.996
Persistence172d
Half-lifeτ
Zero Slope Spline-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.9367 | 4.64*** |
α ARCH Response to squared shocks | 0.0323 | 4.92*** |
β GARCH Volatility persistence | 0.9637 | 135.92*** |
Spline Coefficients
K=1
| γ1 | -0.0001 | -0.35 |
Persistence:
0.996
Half-life:
172 days
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