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cworkman2015
Helper II
Helper II

Z Score calculating incorrectly

Hello,


I'm trying to calculate Z scores by Store with a Calendar Week Slicer. If I select a single week my z scores return correctly, however, if I default to All they inflate. 

 

Here's my formula: 

Sales Units Z Score = 
    var Mean = CALCULATE(SUMX(Values('Calendar'[Week]),[Avg Sales Units]),ALLEXCEPT('Reports DM_STORE','Reports DM_STORE'[Store Number]))
    var StandardDeviation = CALCULATE(STDEV.P('Reports FACT_SUMMARY'[SalesUnits]),ALLEXCEPT('Reports DM_STORE','Reports DM_STORE'[Store Number]))
return (SUM('Reports FACT_SUMMARY'[SalesUnits]) - Mean) / StandardDeviation

 

I tried altering hte STDEV.P formula to the STDEVX.P to iterate over the records, but it still returns the same Z Score when it's all said and done. 

 

Single Week Slicer Results:

StoreNumber: 1; Sales Units Z Score: 2

 

All Week Slicer Results: 

StoreNumber1; Sales Units Z Score: 98.64

 

 

Any idea how I can aggregate appropriately dependent on my slicer selection?

 

Any help would be appreciated!

 

Thanks,
Channing

1 REPLY 1
cworkman2015
Helper II
Helper II

bump

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