Can I understand the desire to keep Group number formatted? Is this an imported field?
I don't see a way around creating a list. 1. Create Group List with codes the same as the number 2. Add a line item in this module above and do a FINDITEM('Group List' , Group) so you have a line item list formatted by "Group" 3. Create another module that sums up the amounts based on the timescale you choose. 4. Order(Sum) will reference the module created in Step #3.