Returns the variance of a sample population.


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


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

Return value

A number that represents the variance of a sample population.



  1. VARX.S evaluates expression for each row of table and returns the variance of expression; on the assumption that table refers to a sample of the population. If table represents the entire population, then you should compute the variance by using VARX.P.
  2. VAR.S uses the following formula:∑(x – x̃)²/(n-1)where x̃ is the average value of x for the sample populationand n is the population size
  3. Blank rows are filtered out from columnName and not considered in the calculations.
  4. An error is returned if columnName contains less than 2 non-blank rows.

This DAX function may return different results when used in a model that is deployed and then queried in DirectQuery mode. For more information about semantic differences in DirectQuery mode.


The following example shows the formula for a calculated column that estimates the variance of the unit price per product for a sample population, when the formula is used in the Product table.

=VARX.S(InternetSales_USD, InternetSales_USD[UnitPrice_USD] – (InternetSales_USD[DiscountAmount_USD]/InternetSales_USD[OrderQuantity]))  

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