There's no definitive, compiled source, and it does vary from school to school completely.
Not every school offers class profiles. Some do, though, and one of them is UCSF:
For fall 2008 -
Degree Held when Entering
00.00% no degree
00.82% Associate's degree
96.72% Bachelor's degree
02.46% Graduate degree
However, that is UCSF. It is reasonable to assume that other schools which don't require Bachelor's degrees, but DO require PCAT, will accept more "no degree" students. This is just a rational thought process on my part. Observation, hypothesis made, and I've experimented a few times by looking through websites of schools that do not require Bachelor's degrees.
Now, let's look at some other schools that have class profiles for the "experiment":
Creighton University
39%
East Tennessee State University
58%
There are probably more, but only some schools have profiles.
Bottom line is this:
yes, at many schools you can get in w/o a bachelors. however, out of 100 students, there's only like 1 or 2 that get in without a bachelors at those schools.
is not entirely accurate at all. If I had more time to go through every single school, and call the ones w/o websites at all, I'm sure I'd find a similar percentage represented all across the states. Creighton and TN are two good examples... 39% and 58%. In CALIFORNIA, it is different, but we don't require PCAT here either, whereas other schools do.
So yeah... take that with a grain of salt