STEYX Function in Excel: Typical Error of a Trend Line

⏱ 1 min readUpdated 28 September 2026

StatisticsLevel: ExpertAvailable in: Excel 2007+

In this article
  1. Syntax
  2. Examples
  3. Example 1
  4. Related functions

STEYX returns the standard error of predicted y values — roughly how far actual points sit from the trend line.

Syntax

=STEYX(known_ys, known_xs)
Argument What it means
known_xs Same length as known_ys.

Examples

Example 1

=FORECAST.LINEAR(A26, C2:C25, A2:A25) + {-2, 2} * STEYX(C2:C25, A2:A25)

A rough low/high band around a forecast.

RSQ · FORECAST.LINEAR

📚 Part of the free Excel course: Beginner → Expert · Try it in the Formula Lab or ask the AI Helper.

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