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V-Lab

Vanguard S&P 500 Index ETF GJR-GARCH Volatility Analysis

Volatility prediction for Monday, July 27th, 2026

1 Day

14.10%

decreased by 0.78%

1 Week

14.15%

decreased by 0.73%

1 Month

14.30%

decreased by 0.58%

Analysis last updated: Saturday, July 25, 2026 at 09:13 AM UTC

Date Range:

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to

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

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graph of Vanguard S&P 500 Index ETF GJR-GARCH

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Nov 8, 2012 to Jul 24, 2026

Model Insight

Volatility shocks decay with a half-life of 13 trading days, meaning a shock loses half its impact after approximately 13 days.

σ

GJR-GARCH Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

0.0430
16.19***
α

ARCH

Response to squared shocks

0.0000
0.00
β

GARCH

Volatility persistence

0.8487
186.48***
γ

leverage

Additional response to negative shocks

0.2017
16.68***

Persistence:

0.950

Half-life:

13 days