Then you can use the formula I gave you, assume all the cells are A1:A12

=SUM(INDEX($A$1:$A$12,ROWS($A$1:A1)*3-2):INDEX($A$1:$A$12,ROWS($A$1:A1)*3))


copy down will sum A1:A3, A4:A6 and so on


--

Regards,

Peo Sjoblom

http://nwexcelsolutions.com


"Justin Hoffmann" wrote in message
...
JAN (for January) is any particular cell. Let's say it is A1, February is
A2, March is A3, and so on.

So my first formula is SUM(A1:A3). But when I copy it to a cell below, I
get SUM(A2:A4), when what I really want is SUM(A4:A6), followed by
SUM(A7:A9), and SUM(A10:A12) to round out the year.

I also want to be able to use this formula across columns as well.

I tried playing around with the formula you gave below, but I'm really a
novice when it comes to excel formulas, and it gives me a #NAME? error.



in article , Peo Sjoblom at
wrote on 5/11/06 3:49 PM:

It's not a problem but we need to know what JAN:MAR means? Is JAN a
defined
name for a group of cells like A1:A30 or is JAN the name of one cell? If
the
latter you could use

=SUM(INDEX(MyRange,ROWS($A$1:A1)*3-2):INDEX(MyRange,ROWS($A$1:A1)*3))

and copy down

will sum first 3 cells, then starting with the 4th cell next 3 cells and
so
on, this can of course be applied to larger ranges as well and although
it
might be shorter to use OFFSET this version is non volatile whereas
OFFSET
or INDIRECT are not