% Variation of week sessions

[MontsePuig]

Hi,

I need to create a variation % between the current week and the previous week. In excel formula ((sessions - (sessions-1)) / (sessions-1). But, I don't know with DAX expressions. 

This is a table

And this is a result that I want. Thank's for help  !!

[v-caliao-msft]

Hi @MontsePuig,

You can use Lookupvalue function to get last week session. Lookupvalue returns the value in result_columnName for the row that meets all criteria specified by search_columnName and search_value.
LOOKUPVALUE( <result_columnName>, <search_columnName>, <search_value>[, <search_columnName>, <search_value>]…) 

Test data Table

Create a table by using DAX below.
Table 2 = SUMMARIZE('Table','Table'[Year],'Table'[Week],"WeekTotal",CALCULATE(SUM('Table'[Sessions]),ALLEXCEPT('Table','Table'[Year],'Table'[Week])))
Create two calculated column.
LastWekkSession = LOOKUPVALUE('Table 2'[WeekTotal],'Table 2'[Year],'Table 2'[Year],'Table 2'[Week],'Table 2'[Week]-1)
Var Session = FORMAT(('Table 2'[WeekTotal]-'Table 2'[LastWekkSession])/'Table 2'[LastWekkSession],"0.00%")

Regards,

Charlie Liao

[MontsePuig]

Hi, @v-caliao-msft , thank you very much for your help!!

This is a result, thanks  

But, now, I have problem with the relationship new table 2 between table. You can see this file.

 

Thank's