Count - Special case

Hello,

In my excel sheet i have two columns like A (Model) and B(Sl.No),few models are repeated with same serial number. so i need to count it without duplication.so i use this formula.
=COUNT(1/FREQUENCY(IF(A2:A100&B2:B100<>"",MATCH(A2:A100&B2:B100,A2:A100&B2:B100,0)),ROW(A2:A100)-ROW(A2)+1))

Then i got the total count of model(Ex:2523 C) - serial number(Ex:MEC45KHJUH41) without duplication(15),but i need to know the count of each models in the result of 15. Please find the attachment and see the commends inserted for more details.

Please help me, i tried and left 2 days for this.