Comparing multiple columns as rows

Hi lpd82 ,

Based on my test, 

1. Create a new table with summarized data

Table = 
VAR _T =
    CROSSJOIN (
        { "Sum of Sales", "Sum of COS", "Sum of GP" },
        VALUES ( Data[Month] )
    )
RETURN
    ADDCOLUMNS (
        _T,
        "Sum",
            VAR _m = [Month]
            RETURN
                SWITCH (
                    [Value],
                    "Sum of Sales", CALCULATE ( SUM ( Data[Sales] ), FILTER ( 'Data', 'Data'[Month] = _m ) ),
                    "Sum of COS", CALCULATE ( SUM ( Data[COS] ), FILTER ( 'Data', 'Data'[Month] = _m ) ),
                    "Sum of GP", CALCULATE ( SUM ( Data[GP] ), FILTER ( 'Data', 'Data'[Month] = _m ) )
                )
    )

2. As you mentioned, you have two slicers to select months and you want to dynamically change the column/measure names.

To be more effective, I'd suggest you use only one slicer for multiple selections:

Var = 
VAR _min =
    MIN ( 'Table'[Month] )
VAR _max =
    MAX ( 'Table'[Month] )
RETURN
    IF (
        HASONEVALUE ( 'Table'[Month] ),
        MAX ( 'Table'[Sum] ),
        CALCULATE ( MAX ( 'Table'[Sum] ), FILTER ( 'Table', 'Table'[Month] = _max ) )
            - CALCULATE ( MAX ( 'Table'[Sum] ), FILTER ( 'Table', 'Table'[Month] = _min ) )
    )

Here is the final output :

Best Regards,
Eyelyn Qin
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