SamePeriodLastYear not working as expected

Hi, 2366 

May I ask if this is the expected output you are looking for? Based on your description, the SamePeriodLastYear function is not returning the expected result in the data model. Here is what might be happening:

1.When you use ‘DATESMTD(DimDate[Date])’, it returns the dates from the start of the month to the current date in the month.

2.When you wrap ‘SamePeriodLastYear’ around ‘DATESMTD’, it attempts to find the same period last year. However, if the current month is not complete, it may return the full month from the previous year.

To fix this issue, you can create a measure that checks if the current period is complete and then apply ‘SamePeriodLastYear’ accordingly. Here is how you can modify your measure:

Measures:

Date Ranges1 =
VAR CurrentPeriod =
    DATESMTD ( DimDate[Date] )
VAR LastYearPeriod =
    SAMEPERIODLASTYEAR ( CurrentPeriod )
VAR MinDateCurrentPeriod =
    MINX ( CurrentPeriod, DimDate[Date] )
VAR MaxDateCurrentPeriod =
    MAXX ( CurrentPeriod, DimDate[Date] )
VAR MinDateLastYear =
    MINX ( LastYearPeriod, DimDate[Date] )
VAR MaxDateLastYear =
    IF (
        MAX ( DimDate[Date] ) = TODAY (),
        MaxDateCurrentPeriod - 1,
        MAXX ( LastYearPeriod, DimDate[Date] )
    )
RETURN
    CALCULATE (
        MIN ( DimDate[Date] ) & "-"
            & MAX ( DimDate[Date] ),
        LastYearPeriod
    )

If this does not work, could you please share some sample data without sensitive information and expected output.
How to provide sample data in the Power BI Forum - Microsoft Fabric Community

Best Regards,
Yang
Community Support Team

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If I misunderstand your needs or you still have problems on it, please feel free to let us know. Thanks a lot!

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