I have the same issue. I pay based off of last years but my growth rate leads me to paying more at the end of the year because of the gain. I am not sure there is a way to be accurate until sales level out a little more and growth slows.
10% of your customers are 90% of the problem.
You may think the grass is GREENER on the other side, but if you take the time to water your own grass would be just as GREEN[/COLOR].