Hi,

Have you checked Tools>Options>Calculation? Automatic should be selected.

HTH

"Miriam" wrote:

> I am always using the sum formula to add up preceding cells and somehow the
> formula has stopped working automatically. If I change one of the preceding
> cells to a different number, the formula cell does not automatically change.
> I have to go back and erase the formula and re-type it in to get the correct
> number. Please advise.