If you tried to put Bob's formula in column A, it should have warned you of
a circular reference (which you could cure by restricting the A:A range).
Try it in column B (and remember it needs C.S.E.).
--
David Biddulph

"gotta know" wrote in message
ups.com...
Hmm. I tried the above, but returns 0.

What I am looking to do...

A1 = (sum of last 25 values in column A)

cell value

a5 2
a6 4
...
a38 0
a39 2
a40 3
a41 0

(I would like to have A1 sum up the last 25 values as soon as the data
are input into column A)