Excel 2007 : Count last N values...

[NomadeWolf]

Hi!

I have a spreadsheet where i have this column where i insert values.
Whenever i new to add a new value, i insert a new row, so i can add the new value at the top most cell.
The thing is i need the sum of the last 25 values, which means the first 25 starting from the top. But when i insert a new value the formula automatically starts counting a position lower...
I tried locking the cells manually by adding $ before the row number, but it doesn't work...

Is there any way i can do this without having to update the formula every time i insert a new value?


Thanks

[daddylonglegs]

To always sum A2:A26 try this formula

=SUM(OFFSET(A1,1,0,25))

That will be OK so long as you don't insert the new row right at row 1, otherwise INDIRECT, i.e.

=SUM(INDIRECT("A2:A26"))