calculate running sales for previous years

[Julia1234]

Hi , I am looking for help to calculate calculate running/rolling sum sales for Previous years Contract Amt.
Year | Month | CustomerGroup| Customer | Contract | Contract Amt | Previous years Contract Amt

2020  11            1                     Smith         S12345      $100                  0

2021  12            1                     Smith         S12345      $200                  $100

2022    1            1                     Smith         S12345      $90                    $300

2022    1            1                     Smith         S12345      $120                  $300

2023 ...

I tried this, but this returns Contract Amt for ALL Customers

Previous years Contract Amt = CALCULATE (
SUM ( Table[Contract Amt] ),
ALL(Table) ,Table[Year] < EARLIER( Table[Year]
))

Thank you in advance

[Jihwan_Kim · Accepted solution]

Hi,

I am not sure if I understood your question correctly, but I tried to create a sample pbix file like below.

Please check the below picture and the attached pbix file.

It is for creating a new column.
I hope the below can provide some ideas on how to create a solution for your datamodel.

Prev Year Contract Amount CC =
SUMX (
    WINDOW (
        1,
        ABS,
        -1,
        REL,
        GROUPBY (
            Data,
            Data[Year],
            Data[Customer],
            "@amountsum", SUMX ( CURRENTGROUP (), Data[Contract Amount] )
        ),
        ORDERBY ( Data[Year] ),
        ,
        PARTITIONBY ( Data[Customer] )
    ),
    [@amountsum]
)

[Julia1234]

Thank you @JihwanKim , this is very helpful, I was looking for exactly this - dax window function.