On my academic home page, I list my bachelor's degree as being in 2002 and my masters as 2003...although technically I received them both in 2003. How can this be? Well, Stanford has this funky little program called the "coterminal" degree, in which one can work on a bachelors and masters degree simultaneously, and then finish them at the same time ("co-terminate" them?). This is known colloquially as "coterming." A number of people finish the bachelors early, and thus they don't really "co-terminate" the degrees, but in order to take certain classes (like Philosophy 189) I decided to finish them both off in the spring of 2003.
Okay, so why list my BS as being from 2002? Well, for all intents and purposes, I'm more of a 2002 person--my last year I was living in graduate housing and doing pretty much all grad school stuff. The bulk of my college friends--especially my oldest friends from freshman year--are in the class of 2002. As the Alumni Association puts it, my "social class year" is 2002. So, since it makes things less confusing for everybody, I go ahead and put down 2002, although it's technically 2003.
This is way more information than you probably wanted, so you probably want to just go back.