Max month in table with data

Hi, TravisGlanzer 

Try  measure as below:

Qtr_monthno = 
    RANKX (
        FILTER ( ALL ( 'BdgDate' ), BdgDate[Quarter] = MAX ( BdgDate[Quarter] ) ),
        CALCULATE ( MAX ( BdgDate[Date] ) ),
        ,
        ASC
    )
//Rank of month in each quarter

Max_Qtr.No = 
MAXX (
    FILTER (
        BdgDate,
        (
            BdgDate[Quarter] = MAX ( BdgDate[Quarter] )
                && [ReportBuilderEntCurrentDonorBase] <> BLANK ()
        )
    ),
    [Qtr_monthno]
)
//max month where data exists for actuals

Result = 
CALCULATE (
    MAX ( 'VW_AGGR_DONOR_BASE'[Donor Base] ),
    FILTER (
        ALL ( BdgDate ),
        ( BdgDate[Quarter] = MAX ( BdgDate[Quarter] ) )
            && [Max_Qtr.No] = MAXX ( BdgDate, [Max_Qtr.No] )
    )
)

Best Regards,
Community Support Team _ Eason
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