In a way this is an interesting way to generalize a little about the genres, recording styles and feels that somebody likes. Like me saying 72 and Batmon saying 79, you can probably make some accurate assumptions about the sounds each of us like just from that without even getting into any specific genre tastes.
I dunno looking at the whole of (say popular) music for a year is just kind of an interesting way to think about old music without thinking about the usual things like genres, specific artists etc.