Standard Deviation by Last 3 Fiscal Years and Fiscal Week

[Anonymous]

Hi there, i am still relatively new to powerbi and enjoying learning as I go. I seem to be having a problem with my measure to calculate standard deviation by fiscal week.

My current measure is:

STANDARD DEVIATION LAST 3 YEARS =
CALCULATE(STDEVX.P(VALUES('FW REF'[FW WeekNumber]),
                          [LAST 3 FISCAL YEARS]),
                                                ALLSELECTED( 'FW REF') )

However, this is bring back the wrong value. I have checked that my '[LAST 3 FISCAL YEARS]' calculation is correct. So i am unsure why is bringing back the wrong standard deviaition?

Thanks in advance 🙂

[amitchandak]

@Anonymous , any reason to choose week number , not tale or table thing else