Calculate difference between two values in same column

Hi, Kadrimedquali 

I have simply simulated some data that I hope fits your situation, and you can try the following methods.

Measure =
IF (
    HASONEVALUE ( 'Table'[Year] ),
    SUM ( 'Table'[Value] ),
    CALCULATE (
        SUM ( 'Table'[Value] ),
        FILTER (
            ALL ( 'Table' ),
            [Year] = 2021
                && [Category] = SELECTEDVALUE ( 'Table'[Category] )
        )
    )
        - CALCULATE (
            SUM ( 'Table'[Value] ),
            FILTER (
                ALL ( 'Table' ),
                [Year] = 2020
                    && [Category] = SELECTEDVALUE ( 'Table'[Category] )
            )
        )
)

Change the name of the column Total to Difference. The results are shown in the figure.

Is this the result you expect?

Best Regards,

Community Support Team _Charlotte

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