Calculate difference between values per category at irregularly spaced dates

Hi Anonymous ,

We can create measure use following formula to meet your requirement:

LastChange = 
VAR LastDay =
    MAX ( 'Table'[Date] )
VAR LastTwoday =
    CALCULATE ( MAX ( 'Table'[Date] ), FILTER ( 'Table', [Date] < LastDay ) )
RETURN
    CALCULATE (
        SUM ( 'Table'[MyValue] ),
        FILTER ( 'Table', 'Table'[Date] = LastDay )
    )
        - CALCULATE (
            SUM ( 'Table'[MyValue] ),
            FILTER ( 'Table', 'Table'[Date] = LastTwoday )
        )

If use your index column, this formula can be more easier:

LastChangeUseIndex = 
CALCULATE (
    SUM ( 'Table'[MyValue] ),
    FILTER ( 'Table', 'Table'[IndexCategory] = MAX ( 'Table'[IndexCategory] ) )
)
    - CALCULATE (
        SUM ( 'Table'[MyValue] ),
        FILTER ( 'Table', 'Table'[IndexCategory] = MAX ( 'Table'[IndexCategory] ) - 1 )
    )

BTW, pbix as attached.

Best regards,

Community Support Team _ Dong Li
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