I would set up a helper cell, using the formula:

=1-sum(a1:a3)

Adjust the range to suit. It will decrease as you enter data in your three
cells.

Regards,
Fred.

"Abe" wrote in message
...
Hi all,

I have 3 cells and have a total of 100% and want to enter in a % into one
cell say 40%, from there that would leave me with 60%. IM trying to
figure
out how to change one cell and then have the 100% decrease so that I dont
ever go over the 100% for my range of cells. This way if on the second
cell
I enter 40% then I only can put in 20% on the last cell.

Hope that makes sense.

Thanks!