I was bored, so I went through the list and counted the guys I thought "worked out". Generally I counted the guys that started a significant amount of time. I didn't go past 2006, because I figure it's a bit soon to evaluate those classes. Here's out it broke down. I broke it down into the Star rankings from all classes combined and then I went and did all the combined ranks in each class.
5 Stars: 7/10, 70%
4 Stars: 31/50, 62%
3 Stars: 19/41, 46%
2 Stars: 7/15, 47%
2002: 16/25, 64%
2003: 9/22, 41%
2004: 16/24, 67%
2005: 15/26, 58%
2006: 8/22, 36%