Scott McKinney at Royals Review posted a comprehensive study of Baseball America’s top 100 prospects lists from 1990 through 2003, attempting to find some patterns in prospect success. The above graph comes from his post and shows the average annual WAR accumulated by a player during his first six big league seasons (his time under team control) versus his rank in the various top 100 lists. As you can see, it’s rather sharp drop off after the top five or six prospects, and the difference between a prospect ranked in the middle of list and the guy ranked 100th really isn’t all that big, about a quarter of a win per season.
This is pertinent to Yankees fans because when BA’s 2011 top 100 list comes out next Wednesday, Jesus Montero figures to rank among the five best prospects in the game. McKinney found that 52.5% of the top 20 prospects go on to become successful big leaguers (defined as 2.0 WAR per season), an excellent success rate when you consider that approximately 70% of all top 100 prospects flame out. Furthermore, position players ranked in the top ten turn into a successful big leaguer a whopping 62.7% of the time, and a “superior player” (2.5 WAR or more) a little more than 35% of the time. Based on history, there’s better than a 50-50 chance that Montero will turn into a useful player, and better than a one-in-three chance that he develops into no worse than above-average player. I like those odds.
McKinney breaks the data down a million different ways, so I highly recommend clicking through and giving his post a read. It turns out that of the 34 Yankees farmhands to appear in BA’s top 100 lists through the years, 73.5% end up busts. That sounds like a lot, but it’s exactly middle of the pack. The Indians lead the way with a 42.4% success rate and the Giants trail everyone at 13%. Again, make sure you check it out. That’s some great stuff right there.