Week needs data from previous week - problem with filter context?

Hi,

Thanks for the solution bhanu_gautam  offered, and i want to offer some more information for user to refer to.

hello MikkoL , you can refer to the following sample.

Sample data 

Sample  measure

Sum = SUM('Table'[Column2])

Create a new table

Table 2 = SUMMARIZE('Table',[Year],[Weeknum],[Year-Week])

Then create the following measures.

Currentsales =
VAR a =
    CALCULATE (
        SUM ( 'Table'[Column2] ),
        FILTER ( 'Table', 'Table'[Year-Week] IN VALUES ( 'Table 2'[Year-Week] ) )
    )
RETURN
    a

LastSales =
CALCULATE (
    [Sum],
    FILTER (
        'Table',
        [Weeknum]
            = SELECTEDVALUE ( 'Table 2'[Weeknum] ) - 1
            && 'Table'[Year] IN VALUES ( 'Table 2'[Year] )
    )
)

Then put the following field to the matrix.

Output

Best Regards!

Yolo Zhu

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

Thank you Anonymous and bhanu_gautam for your great help.
Actually here is a solution that works and it is a combination from both of your answers:
BR, Mikko