Since there’s no absolute metric to determine the most popular song of each year, this compilation opted to use the song that was the Billboard #1 single for the most consecutive weeks in a given calendar year (in America, you can see the UK edition here).

This methodology of course generated some controversy and raised questions; some of which we’ve copied and pasted below:
 
Q: Where is Michael Jackson? Nirvana? Queen? Led Zeppelin?
A: I love all those artists, but THIS LIST IS ENTIRELY BASED ON WHICH SONG SPENT THE MOST WEEKS AT #1 ON THE US BILLBOARD CHARTS EACH YEAR. I didn’t just choose my favorite songs. And neither “Beat It,” “Billie Jean,” “Thriller,” “Bohemian Rhapsody,” nor “Smells Like Teen Spirit” spent the most time at #1 in the years they were released. Hard to believe, I know, but if you’re upset about that, blame the American public.

Q: Where is “One Sweet Day”? It holds the record for most weeks at #1 on the Billboard charts.
A: Good question! This is true, but that song topped the charts at the very end of 1995 and carried over into 1996, so technically it wasn’t the most popular song of either year. Based on the rules of this list, it got beaten by other songs. Just bad timing.

Q: Where is “Gangnam Style”?
A: This list doesn’t include YouTube views, and “Gangnam Style” surprisingly never made it to #1 in the US — I guess most people just watched the video online.

Q: _ is one of the best-selling albums of all time. Why isn’t it on here?
A: Because this list is all about songs/singles, not album sales.

Q: Hey, didn’t you post this video before? What happened to the old one?
A: Yes, but I had to re-post it due to copyright claims. I removed the two clips and uploaded it again.
 
via Sutherland on Youtube