Select the last day value dynamically

Please see this post regarding How to Get Your Question Answered Quickly: https://community.powerbi.com/t5/Community-Blog/How-to-Get-Your-Question-Answered-Quickly/ba-p/38490

Second, MAX and MAXX are your friends in this case. So, if you select a month in some sort of Month slicer then I assume that all of the days for September will be in context so you could do something like:

Measure = 

  VAR __maxDate = MAXX('Some Table',[Date])

RETURN

  MAXX(FILTER('Some Table',[Date] = __maxDate),[Value])

This is all purely conjecture because I don't have any example source data.

Try

Last Day of month Sales = CALCULATE(SUM(Sales[Sales Amount]),filter(sales,Sales[Sales Date]=ENDOFMONTH('Date'[date])))

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Thanks.

My Recent Blog - https://community.powerbi.com/t5/Community-Blog/Comparing-Data-Across-Date-Ranges/ba-p/823601

Hi Anonymous ,

Here I have created a sample for your reference. We can use a measure as below to work it out.

Measure = 
VAR LASTDAY =
    CALCULATE ( MAX ( 'Table'[date] ), ALLSELECTED ( 'Table' ) )
RETURN
    CALCULATE (
        SUM ( 'Table'[value] ),
        FILTER ( 'Table', 'Table'[date] = LASTDAY )
    )

For more details, please check the pbix as attached.