Thanks Barbara! Others have also said that my data may be scewed because of the types of PWP's I'm getting data from. My teacher (and mother!) and I talked about it and I'm going to try to find some statistics from organizations like the one you suggested -- thanks, by the way, for telling me how to find it on search. I'm also going to ask a few of the people I know who have PD -- my grandpa, one of my step-grandma's friends, etc. -- also one of my friend's parents are lawyers doing a case on PD, so they might help. Thanks again for your info and suggestions! Becky