I have a rank table as below which is merged with my FactTable. Previous_Amount works find until I select 2 non consecutive FYandFWOnum number.

    FYandFWOnum  Rank
    202448       1
    202452       2
    202504       3
    202509       4
    
Previous_Amount =
CALCULATE( 
            SUM(FactTable[Amount]),
            KEEPFILTERS('FactTable'[Rank] = MAX('FactTable'[Rank] ) - 1
    ))

the problem

Expected Result

when the is non consecutive numbers are chosen, Previous Amount should be, in this case, not 202504 but 202448