How much is Derek Jeter worth?

Derek Jeter is entering the final season of a 10-year, $189 million contract he signed in 2001, and every baseball fan is wondering the same thing: How big will his next contract be?

To answer that, we need to figure out how good we think he will be from 2011 onward. One way to determine this is to use a metric called WAR (Wins Above Replacement), which I helped develop and accounts for hitting, fielding and baserunning. BaseballProjection.com has the annual WAR for all players through 2009, and the numbers can be used to put Jeter's future value in context.

In his past four years, at the ages of 32 to 35, the New York Yankees shortstop has accumulated 20 WAR. Of all players born since 1895, there have been 90 players who have accumulated at least 15 WAR from ages 32 to 35 (and who played at age 36). The average of this group is 20 wins, which puts Jeter smack in the middle. Babe Ruth and Willie Mays top the list with 43 and 40 WAR, respectively.

How did these 90 players do from the age of 37 onward? This is particularly relevant for Jeter, who turns 37 in June 2011. The player with the most productive career from age 37 on is Barry Bonds, with 56 wins. After that, we have Mays and Ruth with 23 and 21 wins. At the bottom are a few players who did not play past age 36, or played at a below-average level. The average for these 90 players was a total of six WAR for the remainder of their careers. This is an astoundingly low number. The value of a win on the free-agent market is between $4 million and $5 million dollars, so if Jeter ages in line with the average of this group, he will be worth a maximum of $30 million from 2011 onward (6 WAR x $5 million).

It's safe to assume that Jeter is a unique talent, so what if we consider only the 31 players with at least 21 wins from the ages of 32 to 35 (thereby putting Jeter just below the very best players for this age range)? These players averaged just 10 wins from the age of 37 onward, which is still not an impressive number, but would put Jeter's value at somewhere close to $50 million for his next contract -- if he ages gracefully.

Now, let's take the 21 players from this group of 90 who had their best season in this age range at 36. Those players still averaged only 12.5 wins from age 37 onward. That means that if Jeter manages to be better than he was last season, when he had 6.5 WAR, then in the best-case scenario he could be worth up to $60 million for 2011 and beyond.

The worst-case scenario is, of course, zero.

Tom Tango writes for Inside The Book.