Jon Keegan scraped the playlist from the local radio station’s all-Christmas playlist for a few days. Then he looked at play counts and and original composition dates:
Considering the year in which each song was written, my dataset spanned 484 years of published music. Of course, many of the older songs are considered “traditional” songs, without a clear writer or composer. One obvious thing about this genre is that it is rich with covers (performing a new version of someone else’s song). Of the 1,510 songs played over this period that I was examining, it turns out there are really only about 80 unique songs in the dataset. But from those 80 songs come lots of covers, medleys and live recordings.