Who are baseball's best baserunners this year?

In the last three editions of The Bill James Handbook, we introduced a new statistic to measure baserunning.  It's called Net Baserunning Gain and it's simply how many extra bases beyond average a player gains.  For example, a runner goes first to third on a single about 30 percent of the time.  The average is three out of ten.  If a given player goes five out of ten, he is plus two.  We look at all the situations like this, scoring from first on a double, scoring from second on a single, and so on and so forth. If a player is thrown out on the bases, he receives a triple penalty (-3).  And we count stolen bases, but it's only a plus if it's better than a success rate of two out of three (67 percent).

It makes a difference.  The top ten baserunning teams are a collective 58 games over .500 and the bottom ten are 51 games under .500.

Here are the best (and worst) baserunning teams so far this year.

Here are the best and worst baserunners.

For a complete discussion of this new statistic, The Bill James Handbook 2008 has an essay by Bill James that goes into detail.

Source: BillJamesOnline.com (through the games of Tuesday, July 22, 2008)