Copying Sum Formulas

[Justin Hoffmann]

Hello,

In a lot of my work, I take monthly data and compress it into quarterly data
for reports. I use the Sum function to do this and I am looking for an easy
way to replicate the formula.

Here's my problem: Say I have data in a column covering January through
December. Elsewhere, I have a formula to calculate the First Quarter
results SUM(JAN:MAR). But when I copy this formula, I usually end up with
something like this in the subsequent cells:

SUM(FEB:APR)
SUM(MAR:MAY)
SUM(APR:JUN)
And so forth.

I realize that this is because of the position of the formulas in relation
to the original data on the spreadsheet. I could simply copy and paste the
formula every three spaces down, but I don't want to have unused space
between my quarterly formulas.

Is there something I can do to the original formula so that when I copy it,
it knows to move down three cells, rather than one? I.e., so I can copy it
many times and get this:

SUM(JAN:MAR)
SUM(APR:JUN)
SUM(JUL:SEP)
SUM(OCTEC)
SUM(JAN:MAR)
And so forth . . . .


Thanks for your help.

 

[Peo Sjoblom]

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

--

Regards,

Peo Sjoblom

http://nwexcelsolutions.com

 

[Justin Hoffmann]

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.

 

[Peo Sjoblom]

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