Calculated columns for previous weeks values

Hi, akfir 

You can try the following methods.

Column:

Rankweek = RANKX(FILTER('Table',[SKU]=EARLIER('Table'[SKU])&&[Region]=EARLIER('Table'[Region])),[Year_Week],,ASC)

-1 Week = 
Var _week1=MAXX(FILTER('Table',[SKU]=EARLIER('Table'[SKU])&&[Region]=EARLIER('Table'[Region])&&[Rankweek]<EARLIER('Table'[Rankweek])),[Rankweek])
Return
CALCULATE(SUM('Table'[Share]),FILTER('Table',[SKU]=EARLIER('Table'[SKU])&&[Region]=EARLIER('Table'[Region])&&[Rankweek]=_week1))

-2 Week = 
Var _week2=MAXX(FILTER('Table',[SKU]=EARLIER('Table'[SKU])&&[Region]=EARLIER('Table'[Region])&&[Rankweek]<EARLIER('Table'[Rankweek])-1),[Rankweek])
Return
CALCULATE(SUM('Table'[Share]),FILTER('Table',[SKU]=EARLIER('Table'[SKU])&&[Region]=EARLIER('Table'[Region])&&[Rankweek]=_week2))

-3 Week = 
Var _week3=MAXX(FILTER('Table',[SKU]=EARLIER('Table'[SKU])&&[Region]=EARLIER('Table'[Region])&&[Rankweek]<EARLIER('Table'[Rankweek])-2),[Rankweek])
Return
CALCULATE(SUM('Table'[Share]),FILTER('Table',[SKU]=EARLIER('Table'[SKU])&&[Region]=EARLIER('Table'[Region])&&[Rankweek]=_week3))

Is this the result you expect?

Best Regards,

Community Support Team _Charlotte

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