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V-Lab

Proshares S&P 500 EX-Technology ETF Zero Slope Spline-GARCH Volatility Analysis

Volatility prediction for Monday, August 17th, 2026

1 Day

10.13%

decreased by 0.42%

1 Week

10.31%

decreased by 0.24%

1 Month

10.71%

increased by 0.16%

Analysis last updated: Saturday, August 15, 2026 at 02:34 AM UTC

Date Range:

from

to

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

graph of Proshares S&P 500 EX-Technology ETF S0GARCH

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Sep 24, 2015 to Aug 14, 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 7 trading days.

τ

Zero Slope Spline-GARCH Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

0.9147
2.57**
α

ARCH

Response to squared shocks

0.0921
4.07***
β

GARCH

Volatility persistence

0.8176
20.93***
γi Spline Coefficients
K=10
γ1-0.4116
-0.34
γ21.7662
1.03
γ3-2.6687
-2.42**
γ42.2980
2.45**
γ5-2.1595
-2.47**
γ62.7647
3.44***
γ7-3.5802
-5.39***
γ83.6478
5.42***
γ9-2.4888
-3.51***
γ101.0709
2.07**

Persistence:

0.910

Half-life:

7 days