I think I understand what you trying to do. I used the Sample Superstore data as an example for the attached workbook. I create two calculated fields. One identifies the top number of orders in each cell. This formula could be changed to sum the units sold instead of counting distinct orders though. The other field finds the product name associated with the top number of orders. Both of those fields are added to the label. This might not be exactly what you are looking to do, but hopefully it points you in the right direction.
Hope this helps
Book1.twbx 456.9 KB