An "inverse bell curve" - the company goes bankrupt in the middle? Are you confusing Power Curve for Bell Curve?
Symmetric - that should be fun. Maybe enough datapoints to get a more realistic curve-fit, which would allow for some predictive modeling.
Adrenalynn, a bell curve is a "shape" normal data will have this normal pattern when graphed, but you can always have more than one bell curve, or inverse one from one set of data it depends on your results. In this case the data is from one business, so they actually set their own floor which is their lowest. That doesn't have to be on 0, bankrupt. It would simply be a dip in the middle. That gradually climbed back up. Sorry for the initial confusion, but Thanks for the concern.