I am trying to sum total amount spent by account number. Is there a way to
sum a range of cells without having to go in and put the exact number in for
the criteria? For example, I know I can use:

=sumif(a2:a235="101",c2:c235)

But I would like for excel to look at column A and say a2:a6=101 so sum
c2:c6, a7:a8=101 so sum c7:c8, etc. There is not a standard number of items
per account number, and the numbers are in random order (I can sort if I need
to)

Can anybody help?