Ok, I took a class there called Exploring Disney Leadership and we got off topic one class when we were discussing the ratio of leaders to front line cast members and got on the topic of CP acceptance rate. The following info is from the instructor who used to be in international recruiting for the program with NO supporting evidence so take this for what it's worth...
He said that for the previous program (in this case fall/advantage 2011) there had been about 22,000 applicants and around 5,500 acceptances worldwide with about 1,000 declining to do the program and another couple hundred who accepted but didn't show.
So remember he provided no supporting evidence for those numbers so I can't say how accurate they are.