Switching Signs in Power BI

Hello - I recommend you add a mapping table that indicates the desired flip behavior and then relate it to the fact table and incorporate it into your calculation.  

Hi, hoa3nok7 

In this case, I think the flipped amount column is not necessary.
You can use the ISINSCOP function to calculate the total separately.

Modify the above measures as follows:

Measure =
VAR _SUM_AB =
    CALCULATE (
        SUM ( 'Table1'[Amount] ),
        FILTER ( 'Table1', 'Table1'[FISCAL_YEAR] = [Selected Fiscal Year] ),
        FILTER ( 'Table1', 'Table1'[PERIOD] <= [Selected Period] ),
        FILTER ( 'Table1', 'Table1'[Grouping] = "A" || 'Table1'[Grouping] = "B" )
    )
VAR _SUM_CD =
    CALCULATE (
        SUM ( 'Table1'[Amount] ),
        FILTER ( 'Table1', 'Table1'[FISCAL_YEAR] = [Selected Fiscal Year] ),
        FILTER ( 'Table1', 'Table1'[PERIOD] <= [Selected Period] ),
        FILTER ( 'Table1', 'Table1'[Grouping] = "C" || 'Table1'[Grouping] = "D" )
    )
VAR _SUM_ALL =
    CALCULATE (
        SUM ( 'Table1'[Amount] ),
        FILTER ( 'Table1', 'Table1'[FISCAL_YEAR] = [Selected Fiscal Year] ),
        FILTER ( 'Table1', 'Table1'[PERIOD] <= [Selected Period] )
    )
RETURN
    IF (
        ISINSCOPE ( 'Table'[Grouping] ),
        // 1,
        - ( _SUM_AB ) + _SUM_CD,
        // 2
        - ( _SUM_ALL )
    )

If this doesn't work, could you please consdier sharing more details about it and posting expected result so it is clear on what needs to be implemented?  And It would be great if there is a sample file without any sesentive information here. It makes it easier to give you a solution.

Best Regards,
Community Support Team _ Zeon Zheng

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