VARX.P Function (DAX)
Returns the variance of the entire population.
VARX.P evaluates <expression> for each row of <table> and returns the variance of <expression> assuming that <table> refers to the entire population.. If <table> represents a sample of the population, then compute the variance by using VARX.S.
VARX.P uses the following formula:
∑(x - x̃)²/n
where x̃ is the average value of x for the entire population
and n is the population size
Blank rows are filtered out from columnName and not considered in the calculations.
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, see http://go.microsoft.com/fwlink/?LinkId=219171.
The following example shows the formula for a calculated column that calculates the variance of the unit price per product, when the formula is used in the Product table
=VARX.P(InternetSales_USD, InternetSales_USD[UnitPrice_USD] –(InternetSales_USD[DiscountAmount_USD]/InternetSales_USD[OrderQuantity]))