The point I was attempting to make is that one should not be looking at just wrestler data, but the population from which the wrestlers are taken, i.e. the entire student body.
If, for sake of example, the lowest weight class is 100, you would have some small percentage of wrestlers around 100. If on the other hand, the lowest weight class is 125, and you then study the percentage of wrestlers around 100 lbs, you are going to find a lot less of them (because they don't wrestle if they are that small).
Looking at a cohort of 200,000 wrestlers is wrong because it is ignoring all the non-wrestlers that otherwise might wrestle if the weight classes were different. I haven't completed my analysis of the CDC data yet, but suspect that the weights of high school age boys (sorry girls) is normally distributed with more boys in the middle range of weights than at the extremes. Which would argue for more weight classes in the middle weights and less on the extremes. This happens to be exactly the opposite direction these new weight classes are moving.