Add a Difference Row for a group

Hi ak77 ,

Due to I don't know your data model, I create a sample to have a test.

Here I suggest you to create a Header Group table and create a relationship between it with your Fact table.

QTY with difference =
IF (
    HASONEVALUE ( 'Header Group'[Header] ),
    [M_QTY],
    CALCULATE ( [M_QTY], 'Header Group'[Sort] = 1 )
        - CALCULATE ( [M_QTY], 'Header Group'[Sort] = 2 )
)

YTD with difference = 
IF (
    HASONEVALUE ( 'Header Group'[Header] ),
    [M_YTD],
    CALCULATE ( [M_YTD], 'Header Group'[Sort] = 1 )
        - CALCULATE ( [M_YTD], 'Header Group'[Sort] = 2 )
)

Calendar 1 yr with difference = 
IF (
    HASONEVALUE ( 'Header Group'[Header] ),
    [M_Calendar 1 yr],
    CALCULATE ( [M_Calendar 1 yr], 'Header Group'[Sort] = 1 )
        - CALCULATE ( [M_Calendar 1 yr], 'Header Group'[Sort] = 2 )
)

Then create a Matrix visual > Turn of Stepped layout > Turn on the Per row level

>Turn of show subtotal for row level group > Change the subtotal name for row level Header.

Result is as below.

Best Regards,
Rico Zhou

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