Skip to main content
V-Lab
V-Lab

American Express Co GJR-GARCH Volatility Analysis

Volatility prediction for Friday, September 11th, 2026

1 Day

23.46%

decreased by 0.62%

1 Week

23.76%

decreased by 0.32%

1 Month

24.90%

increased by 0.82%

Analysis last updated: Thursday, September 10, 2026 at 09:50 PM UTC

Date Range:

from

to

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

graph of American Express Co GJR-GARCH

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Jan 2, 1990 to Sep 4, 2026

Model Insight

With persistence 0.997, volatility shocks have a half-life of 209 trading days (~0.8 years), close to a unit root, so long-run forecasts are highly sensitive to this estimate.

Leverage: volatility responds almost entirely to negative shocks

σ

GJR-GARCH Model

Tap to view equation

High persistence: persistence 0.997, shock half-life ~209 daysLeverage: volatility responds almost entirely to negative shocks
ParamValuet-stat
ωconst0.0355
4.28***
αARCH0.0172
3.36***
βGARCH0.9277
186.62***
γleverage0.1036
6.66***

0.997

Persistence

209d

Half-life
σ

GJR-GARCH Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

0.0355
4.28***
α

ARCH

Response to squared shocks

0.0172
3.36***
β

GARCH

Volatility persistence

0.9277
186.62***
γ

leverage

Additional response to negative shocks

0.1036
6.66***

Persistence:

0.997

Half-life:

209 days