Are you using the right forumla? If 5, 6, and 7 are in A5, A6, and A7, and
you want the sum in A8, does A8 say =SUM(A5:8) ?

"Kate" wrote:

I have a column of numbers and am trying to do a simple sum at the bottom of
this column, does not work. I have formatted all the numbers to actual
"Number" in Excel but unless I click into each cell, the sum function does
not work. For example:
5
6
7
=18, does not. If I click in the "6" cell, my total sum will now become 6.

Thank you in advance.