I think they only count the times that the ump is working the plate. Roughly 3/4 of umpires are working on a given day, so the average ump works 120 games (give or take). 30 of those would be at the plate.

And I thought I was the only one that tracked runner movement by the uniform number of the hitter! Nick

The Red Sox are a little more recent than the Yankees. They won the Series in 2004 and 2007.