Is this a job for SUMPRODUCT? Or is it easier?

[Bob Phillips]

Ok thanks! Also, I just wanted to check. When I use this
[vba]=SUMPRODUCT((ISNUMBER(Y!$1:$3))*(Y!$1:$3<=Z!A1)*(X!$B$1:$B$3="T"))[/vba]

and I drag the fill handle downwards. Each count also includes those from the count preceding it right?

That is:

In order to find the count in a particular class, I would have to subtract the count from the one before it.

I think I have answered by own question.

I cannot see wht you would copy down, you only need a single count.

So, I presume that if I want the total of ALL cells in "Y" who have a corresponding "T" in "X" in their respective row designations I would leave off the middle condition.

So [vba]Total =SUMPRODUCT((ISNUMBER(Y!$1:$3))*(X!$B$1:$B$3="T"))[/vba]

I would use SUMIF here.