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V-Lab

TLT Percentage Price Volatility Index Zero Slope Spline-GARCH Volatility Analysis

Volatility prediction for Friday, September 4th, 2026

1 Day

65.86%

decreased by 3.07%

1 Week

70.26%

increased by 1.33%

1 Month

78.71%

increased by 9.78%

Analysis last updated: Friday, September 4, 2026 at 11:34 AM UTC

Date Range:

from

to

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

graph of TLT Percentage Price Volatility Index S0GARCH

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Jan 2, 2004 to Aug 28, 2026

Model Insight

This model fits a time-varying baseline (a spline), so volatility mean-reverts toward a slowly-shifting long-run level rather than a constant. Short-run deviations decay with a half-life of 6 trading days.

τ

Zero Slope Spline-GARCH Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

0.9598
7.55***
α

ARCH

Response to squared shocks

0.1533
5.09***
β

GARCH

Volatility persistence

0.7401
15.05***
γi Spline Coefficients
K=5
γ1-0.0398
-1.67*
γ20.0485
1.35
γ30.0297
1.08
γ4-0.0844
-3.14***
γ50.0624
3.19***

Persistence:

0.893

Half-life:

6 days