Hi,

Can someone please help me with a formula that allows me to count unique entries in a column according to two specified criteria.

Specifically, I am trying to count the number of days in a month a supplier has a visited.

Below is an example taken from the excel:

COLUMN A COLUMN B
Date Supplier
01-ago-12 Mr X
01-ago-12 Mr X
01-ago-12 Mr X
01-ago-12 Mr Y
03-ago-12 Mr Y
06-ago-12 Mr X
08-ago-12 Mr X
08-ago-12 Mr X
09-ago-12 Mr Y
09-ago-12 Mr Y
14-ago-12 Mr X
14-ago-12 Mr X
15-ago-12 Mr Y
17-ago-12 Mr X
17-ago-12 Mr Y
01-sep-12 Mr Y
01-sep-12 Mr X
01-sep-12 Mr X
02-sep-12 Mr X
02-sep-12 Mr X

I want a formula that allows me to see how different dates Mr X has visited in each month. So in August he has visited 8 times BUT only on 5 different dates. I am looking for a formula that gives 5 as the answer.

In the case of Mr Y I want the formula to give the answer 5 (even though he has visited 6 times in total, he has visited on only 5 different dates).

In the case of Mr X in September, the answer to the formula would be 2, since has visited on 2 different dates in September.
Would really appreciate the help!

Thanks,

Leopold2000