Skip to main content
V-Lab
V-Lab

American Express Co GJR-GARCH Volatility Analysis

Volatility prediction for Monday, September 14th, 2026

1 Day

22.93%

decreased by 0.52%

1 Week

23.24%

decreased by 0.21%

1 Month

24.41%

increased by 0.96%

Analysis last updated: Friday, September 11, 2026 at 11:44 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 11, 2026

Model Insight

With persistence 0.997, volatility shocks have a half-life of 207 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 ~207 daysLeverage: volatility responds almost entirely to negative shocks
ParamValuet-stat
ωconst0.0355
4.29***
αARCH0.0173
3.38***
βGARCH0.9276
186.37***
γleverage0.1035
6.65***

0.997

Persistence

207d

Half-life
σ

GJR-GARCH Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

0.0355
4.29***
α

ARCH

Response to squared shocks

0.0173
3.38***
β

GARCH

Volatility persistence

0.9276
186.37***
γ

leverage

Additional response to negative shocks

0.1035
6.65***

Persistence:

0.997

Half-life:

207 days