Hi @NL-Nicolas ,
1.Please try to add an index column for two table:
2.add a slicer for with, and create a measure and add it into card visual
VAR cur_index =
SELECTEDVALUE ( Table2[Index] )
VAR cur_table1 =
CALCULATE ( MAX ( Table1[NetSales] ), Table1[Index] = cur_index )
VAR cur_table2 =
CALCULATE ( MAX ( Table2[NetSales] ), Table2[Index] = cur_index )
cur_table1 - cur_table2
Please refer attached .pbix.
Community Support Team_ Binbin Yu
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