Hi

not sure what you're after here, are you wanting the +-1% based on the
difference to the previous month or on a base figure? and what figure is the
1% of? but here's one idea anyway where you're looking at the difference
between B1 and A1 and adding +- 1% of B1 for each whole $10 difference
between B1 & A1

=IF(B1-A10,INT((B1-A1)/10)*(1%*B1),ABS(INT((B1-A1)/10))*(-1%*B1))

Cheers
JulieD

wrote in message
oups.com...
That would be good if it was a simple linear change, but unfortunately,
it isn't. The problem is that it can be $550 one month and $595 another
month, so the formula had to be "smart" enough to recognize how many
$10 differences there are, if it's more or less and add the 1%
accordingly for every $10 +/-. What do you think?