Matrix difference in total with grouping category

Hi JKG ,

Not certain what is the relationship between your another table and this sample table, please check whether you have enabled 'show item with no data' first.

Then I noticed that each total value is wrong when you add the type field to the matrix, based on my test sample, you can try to modify the measure like this:

m =
VAR x =
    CALCULATE (
        SUM ( 'Pilpt Payroll Detail'[Total_CHs_Paid] ),
        FILTER (
            ALL ( 'Pilpt Payroll Detail' ),
            'Pilpt Payroll Detail'[BidMnth] < MAX ( 'Pilpt Payroll Detail'[BidMnth] )
                && 'Pilpt Payroll Detail'[PayCode] IN DISTINCT ( 'Pilpt Payroll Detail'[PayCode] )
        )
    )
VAR y =
    CALCULATE (
        SUM ( 'Pilpt Payroll Detail'[Total_CHs_Paid] ),
        FILTER (
            ALL ( 'Pilpt Payroll Detail' ),
            'Pilpt Payroll Detail'[BidMnth] = MAX ( 'Pilpt Payroll Detail'[BidMnth] )
                && 'Pilpt Payroll Detail'[PayCode] IN DISTINCT ( 'Pilpt Payroll Detail'[PayCode] )
        )
    )
RETURN
    IF (
        HASONEFILTER ( 'Pilpt Payroll Detail'[BidMnth] ),
        SUM ( 'Pilpt Payroll Detail'[Total_CHs_Paid] ),
        IF ( ISINSCOPE ( 'Table'[Type] ), y - x, y - x )
    )

Attached my sample file in the below, hopes to help you.

Best Regards,
Community Support Team _ Yingjie Li
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