Quote Originally Posted by jpgoeth
I have rows of data to which I add new values once a week. I want to sum the last 12 values in the row (the sums will be tied to charts).

I tried =sum(offset(c2,counta(12:12)-12,0,1,-12)), but it doesn't seem right (mostly because it doesn't work).

Can anyone help?

Thanks
JP
Hi,

in A1 try something like

=IF(COUNT(B1:IV1)<12,SUM(OFFSET(B1,0,0,1,12)),SUM(OFFSET(B1,0,COUNT(B1:IV1)-12,1,12)))

which will count either the first 12 columns (B1: ~~) or the last 12 columns, depending on the number of figures found, it will require that no figure cell be blank.

hth
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