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JSE Securities South African Volatility Index GJR-GARCH Volatility Analysis

Volatility prediction for Thursday, September 24th, 2026

1 Day

58.38%

increased by 4.01%

1 Week

59.06%

increased by 4.69%

1 Month

60.91%

increased by 6.54%

Analysis last updated: Friday, September 25, 2026 at 08:56 PM UTC

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Date Range:

from

09/23/2024

to

09/23/2026

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

graph of JSE Securities South African Volatility Index GJR-GARCH

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Feb 1, 2007 to Sep 23, 2026

Model Insight

Volatility shocks decay with a half-life of 12 trading days, meaning a shock loses half its impact after approximately 12 days.

σ

GJR-GARCH Model

Tap to view equation

Shock decay: Shocks decay with a 12-day half-life
ParamValuet-stat
ωconst0.9552
4.43***
αARCH0.1299
3.23***
βGARCH0.8299
32.16***
γleverage-0.0360
-0.48

0.942

Persistence

12d

Half-life
σ

GJR-GARCH Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

0.9552
4.43***
α

ARCH

Response to squared shocks

0.1299
3.23***
β

GARCH

Volatility persistence

0.8299
32.16***
γ

leverage

Additional response to negative shocks

-0.0360
-0.48

Persistence:

0.942

Half-life:

12 days