Rank Groups By Sum Total

I'm trying to set up a formula to rank clients within a salesgroup by their total value.

Normally I'd do this using sumproduct, but it doesn't seem to work in this instance as I get 'gapped' results.

Sample data:

ClientGroupProduct EV
cust AAfricarubber 70
cust BAfricacotton 75,000
cust CAfricarubber 4,384
cust AAfricacotton 51
cust AEuroperubber 234
cust CEuropesteel 5
cust BEuropeconcrete 0
cust CEuropesteel 4,384
cust AEuropeconcrete 28
cust CEuropeconcrete 37,132
cust AEuropecotton 18
cust ANArubber 6,750
cust BNAsteel -
cust ANAconcrete 35
cust BNAsteel 250,000
cust BNAconcrete 30,000
cust ANAcotton 117,470
cust CNAsteel 800

So each Client has multiple entries by product and salesgroup with need to be summed, and then I'd like to rank each client within each salesgroup.

So within each salesgroup I'd like these clients to be ranked 1, 2, 3. (Highest total as 1.)

So for Africa, cust B is 1, C is 2, and A is 3.
Europe - C is 1, A is 2, and B is 3
NA - B is 1, A is 2 and C is 3

Ideally I'd like to not have to sort the data in any way before running the formula.

And I have about >10,000 rows, so an array formula would take a very long time to run.