Create a column when different rows have the same value

Hello Adrian_rev 
You can create a calculated column with the below DAX;

RESULT =

CALCULATE(

    MAX('table_name'[FAMILY_ID]),

    ALLEXCEPT('table_name','table_name'[INVOICE])

)

Please Let me know if this isn't meet your requirement

Thanks & Regards...

Hello Adrian_rev ,

try this

New_Family_ID =

CALCULATE (

    MAX (YourTable[FAMILY_ID]),

    ALLEXCEPT (YourTable, YourTable[INVOICE])

)

Thanks,
 Pankaj Namekar | LinkedIn

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