D.J. Earworm Mashup did a terrific job combining 25 greatest pop hits in 2013. I wonder if each year can be combined like this for study of recurring themes for young adults ?
A young person reviewing all the years would see the recurrent themes and not waste so many years "rebelling, living the fantasy, living the new age, all eyes on us " etc.

Thanks for the mix of old and new on your site.