The numbers don’t jive. Back in the day there was one top 40. It included pop, rock, country, and even some jazz. Go back to that standard and most of those “number one” hits disappear. Today there are rock charts, country charts, and pop charts. Sales can be attributed to online sales. Mp3, iTunes, etc. Great music stands the test of time. That’s why we still listen to rock/pop music from the 50’s, 60’s, and 70’s. While there is some, how much music from the 80’s, 90’s, and 2000’s do you still listen to today?