# DAX Statistical - STDEVX.S function

## Description

Evaluates an expression for each row of the table and returns the standard deviation of an expression, assuming that the table refers to a sample of the population.

## Syntax

STDEVX.S (<table>, <expression>)


## Parameters

Sr.No. Parameter & Description
1

table

A table or any DAX expression that returns a table of data.

2

expression

Any DAX expression that returns a single scalar value, where the expression is to be evaluated multiple times (for each row/context).

A real number.

## Remarks

DAX STDEVX.S function evaluates an expression for each row of the table and returns the standard deviation of expression assuming that the table refers to a sample of the population. If the table represents the entire population, then use DAX STDEVX.P function.

STDEVX.S uses the following formula −

$$\sqrt{\sum\frac{(x\:-\:\bar{x})^{2}}{(n-1)}}$$

Where, $\bar{x}$ the average value of $x$ for the sample population, and

n is the sample size

Blank rows are filtered out from the resulting column and not considered in the calculation.

An error is returned, if the resulting column contains less than 2 non-blank rows.

## Example

= STDEVX.S (West_Sales,West_Sales[Amount])

dax_functions_statistical.htm