It's complicated coming up with a transfer rate for players. There were 796 top-100 players in the recruiting classes of 2002 through 2009 (four players were re-ranked in two different classes). Some of those transferred more than once. Some never saw a college campus. Some showed up in college, got kicked off the team after a semester, and were never heard from again (Matt Simpkins).
So what I've done is taken everyone who lasted a certain number of years with the same school and played the following year. In other words, 711 top-100 players were on Division I rosters at the end of their freshman seasons and didn't leave for the NBA or Europe or have medical problems, and did find another school to attend (JC and D-II included). Of that group of 711 players, 70 transferred.
Sophomore rate is calculated the same way. We include the freshman transfers in the denominator.
Freshman transfer rate: 70/711 = 9.8%
Sophomore transfer rate: 13.8%, 26% of players transfer by their sophomore year
Junior transfer rate: 3.4%, 33% of players transfer by their junior year
Three of the 35 players (8.6%) who had eligibility after their fourth year at the same school transferred for their final year.
If someone said, "What is the transfer rate for Top 100 players?" I'd tell them this:
About one in four players are expected to transfer. Nearly all of them do so before their junior year, although the breakdown between freshmen and sophomore transfers is about even.
I would also tell them that out of all these transfers about one in five come mid-season.
Here's a helpful chart showing how long top-100 players last at their original schools. Whether those players end up leaving their original school for a different program, the NBA, Europe, or a different destination, it's pretty clear that top-20 players behave differently than Nos. 21-100. If you land one of those top-20 stars, be prepared to see them leave sooner rather than later.
Drew Cannon is a college student and a regular contributor to Basketball Prospectus. Follow him on Twitter at @DrewCannon1.
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Drew Cannon is an author of Basketball Prospectus.
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