=SUMPRODUCT(--(MOD(COLUMN(J10:IV10),5)=0),J10:IV10)


"Sam" wrote:

Hello!
I need to create a formula that will sum a series of nonadjacent cells, but
will be able to limit how many of the cells to sum based on the index. For
example, I have a dollar total based on 12 months of data:
cell: J10 O10 T10...
Mo.: Jan Feb Mar...
Amt:$100 $100 $100... and so on

However, months that are in the future have "guesstimate" data in them. I
would like to have a formula that will run on a Year-To-Date basis that will
only sum the ACTUAL data, without having to add a cell each month to include
that new total. (So if executed today, the formula would only sum data for
January through June, but next month, would sum January through July without
having to change anything but the index.)

Any ideas? Thank you!