SUMIF assistance

I have got a worksheet full of data (around 2000 rows and 15 columns). I need to do a sumif to see how often in the data, 2 columns match, to see how many rows have those same 2 values in these 2 columns (reference and address line 1). Can anyone provide any pointers, say for example column A is my "count" column, where I will be applying the SUMIF calculation to get a count, and column B is the reference column, and column C is the address line 1 column.

e.g.
count-reference-address1
---------------------------------------
2-12345-1 EE street
2-12345-1 EE street
1-34567-2 EE street