Sum the last 12 columns ?

[TroyB]

Hi,
I'm embarrased about asking this question!
I've got a table with a number of coulums (say 20) with $values in a number
of rows and i keep adding columns to the last one. How do i sum the last 12
columns in the table (so that i dont have to manually change the range each
time i add a column).

eg

Job Feb03 Mar03 April03 May03 June03 July03 Aug03
Sept03 Oct03 Nov03 Dec03 Jan04 Feb04 Mar04 April04
Total

JobA $87.00 $45.00 $42.00 $87.00 $45.00 $42.00 $87.00
$45.00 $42.00 $87.00 $45.00 $42.00 $87.00 $45.00 $42.00
=Add last 12Col (ie from May 03 to April 04)
Job B $87.00 $45.00 $42.00 $87.00 $45.00 $42.00 $87.00
$45.00 $42.00 $87.00 $45.00 $42.00 $87.00 $45.00 $42.00
=Add last 12Col
Job C $87.00 $45.00 $42.00 $87.00 $45.00 $42.00 $87.00
$45.00 $42.00 $87.00 $45.00 $42.00 $87.00 $45.00 $42.00
=Add last 12Col

Many Thanks

Troy

 

[Harlan Grove]

...
...

I've got a table with a number of coulums (say 20) with $values in a number
of rows and i keep adding columns to the last one. How do i sum the last 12
columns in the table (so that i dont have to manually change the range each
time i add a column).

If the rightmost column of those you want to sum is the last nonblank column, so
that there'd be nothing but truly blank cells to the right of the rightmost
column to be summed, you could use

=SUM(OFFSET($3:$3,0,MATCH(1E+300,$3:$3)-12,1,12))

to sum the rightmost 12 cells in row 3, as long as this formula ian'a also in
row 3.