New answers tagged musicology
Check out this site: http://www.allmusic.com/ It has tons of info that may help. For example they have a chart for R&B 1971. It could help gather some tunes for your goal. http://www.allmusic.com/blog/post/rb-40-1971
I'm not sure if you had a particular country in mind, but http://www.officialcharts.com/archive-chart/_/1/1960/ has UK top 40 charts week by week going back to 1960.
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