1975! Yes, 1991 wasn't bad, nor 1979. But I can't go past 1975 including important contributions from Abba (Mamma Mia), AC/DC (It's a Long Way to the Top), David Bowie (Fame, Young Americans, Space Oddity), Bob Dylan (Tangled Up In Blue), KC & the Sunshine Band (That's The Way - I Like It), Kraftwerk (Autobahn) and Queen (Bohemian Rhapsody); but most of all: Pink Floyd's "Wish You Were Here"
In case you found your way here directly rather than from the blog post, here's the link back: http://www.stubbornmule.net/2009/07/visualizing-the-hottest-100/
Hmmm. I had hoped that "Other" would display the year chosen. Apparently not!