So if a player transfers or leaves but is in good academic standing, then it doesn't count against the APR? I don't think it's JUST attrition. I'm thinking the basketball team has a high APR (could be wrong about that), and they have a ton of attrition.
The way this works for the majority of scholarship athletes is that each player on the team is responsible for 4 "units": 2 for the fall semester and 2 for the spring. Two units are for academic progress and the other two are for retention in the program (or graduation).
-if a player is on scholarship for the fall semester and flunks out, then quits (or transfers to another school), he contributes 0 out of 2 to the program's APR score for that semester.
-If the player flunks out but remains in the program for the next semester (hopefully to get back on track), he contributes 1 out of 2 to the APR score for that semester.
-If the player achieves the required academic progress but then transfers out without graduating, he contributes 1 out of 2 to the APR score for that semester.
-And of course, if the player both achieves and stays in the program for the next semester (or graduates), he contributes 2 out of 2 to the APR score for that semester.
In the case of the one and dones on the basketball team, they typically contribute 2 out of 2 for the first semester and then 0 out of 0 for the next one. This is because the school asks the NCAA for a waiver and provides documentation that the player applied for the NBA draft.