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V-Lab

iShares National AMT-Free Muni Bond ETF GJR-GARCH Volatility Analysis

Volatility prediction for Monday, July 27th, 2026

1 Day

5.04%

decreased by 0.17%

1 Week

5.08%

decreased by 0.13%

1 Month

5.26%

increased by 0.05%

Analysis last updated: Friday, July 24, 2026 at 10:36 PM UTC

Date Range:

from

to

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

graph of iShares National AMT-Free Muni Bond ETF GJR-GARCH

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Sep 10, 2007 to Jul 24, 2026

Model Insight

With persistence 0.996, volatility shocks have a half-life of 187 trading days (~0.7 years), close to a unit root, so long-run forecasts are highly sensitive to this estimate.

Leverage: Negative returns increase volatility 66% more than positive returns

σ

GJR-GARCH Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

0.0013
21.53***
α

ARCH

Response to squared shocks

0.1171
19.68***
β

GARCH

Volatility persistence

0.8407
267.83***
γ

leverage

Additional response to negative shocks

0.0769
7.14***

Persistence:

0.996

Half-life:

187 days