Increase % over 0

I am trying to illustrate a % increase for month over month sales with a formula, where i am running into a problem is when there were $0 sales in 2008 and i get the #DIV/0!.

How do i write a formula to show the % increase if there were $0 sales in 1/08, but 52 in 1/09?

Thanks, John

But won't that still result in a "0", rather than a % increase?

It isn't possible to compute a % increase over a zero value- for example, if sales are 0 in period 1 and then either 10 in period 2 or 20 in period 2, how can you represent either of period 2's results as a % increase?

If period 1 is 0, you'll need to have a formula that states "Prior period sales were 0 therefore a % increase has not been computed".
You could do this by modifying th esuggested solution as follows:

=IF(A1=0,"Prior period sales were 0 therefore a % increase has not been computed",B1/A1*100)

Got it, thanks for the help!