I have trawled the forum and the internet and cannot find a solution. I am likely being dim as I am not an Excel expert so here goes...

I have data in 2 columns for students in a school who have had a detention

Column A has the student name
Column B has the week in the term they have detention

it looks something like below:

Student Week
Anna 1
Matt 2
Anna 2
Steve 3
Anna 4
Matt 4
Anna 4

I need to be able to count the number of different values in column A, so here it would be 3 as there are 3 different students. I also need to be able to count the number of different values in column A in the different weeks. as I need to be able to say how many different students have had detentions each week, e.g.1 in week 1, 2 in week 4 because Anna had 2 in one week.

It would be most appreciated if anyone has any pearls of wisdom. Ta muchly in advance