VARX.P retruns minus value in dax, why?

[Fariba1984]

Hi experts,

I would like to calculate Variance of some values with this dax code:

Gesamtauslastung:= 

var x=  SUMX(CheckoutUtilization;CALCULATE(((CheckoutUtilization[NumberOfParallelCheckouts] / CheckoutUtilization[MaxNumberOfCheckouts])* CheckoutUtilization[MinutesOfParallelCheckoutUsage]) / CheckoutUtilization[DailyTotalMinutesOfCheckoutUsage];CheckoutUtilization[Date_SID];CheckoutUtilization[_NumberOfParallelCheckouts]))
return CALCULATE(VARX.P(CheckoutUtilization;x);ALLSELECTED('date'))

But what I see as result is minus values, as I understood Variance is allways +. Why do I get such a result?

1- I would like to calculate variance of these values.
As you can see reault of variance is minus

[Anonymous]

These are NOT negative values. These are 0's. What you see is the outcome of rounding at the machine level. You get 0's because variables in DAX are not recalculated, they retain their value throughout the entire calculation. So, they are set in stone once you define them. Your x never changes, hence you see 0's.

[Anonymous · Accepted solution]

[Auslastung] = 
    SUMX(
        CheckoutUtilization,
	CheckoutUtilization[NumberOfParallelCheckouts]
	/ CheckoutUtilization[MaxNumberOfCheckouts]
    	* CheckoutUtilization[MinutesOfParallelCheckoutUsage]
        / CheckoutUtilization[DailyTotalMinutesOfCheckoutUsage]
    )

Gesamtauslastung :=
    CALCULATE(
        VARX.P(
            CheckoutUtilization,
            [Auslastung]
        ),
        ALLSELECTED( 'date' )
    )

You need something like the above...

[Greg_Deckler]

@Fariba1984 - VARX.P uses the formula:

∑(x - x̃)²/n

So if n is negative, I suppose you will get negative results.

[Fariba1984]

It is population size and population size can not be  negative

[Greg_Deckler]

@Fariba1984 - Well, it wouldn't be the first time I found weirdness with DAX functions. https://community.powerbi.com/t5/Quick-Measures-Gallery/To-bleep-with-MOD/m-p/1081806#M509

You could check the Issues forum here:

https://community.powerbi.com/t5/Issues/idb-p/Issues

And if it is not there, then you could post it.

If you have Pro account you could try to open a support ticket. If you have a Pro account it is free. Go to https://support.powerbi.com. Scroll down and click "CREATE SUPPORT TICKET".