When Peter, Björn and John first released the single Young Folks in May of 2006, it shuffled into the charts at number 33 and then promptly shuffled back out again.
On its re-release in September of this year, though, it went straight into the top 20 and is still hanging around with steady weekly sales. The intervening year or so saw Young Folks picking up many Best Song Of 2006 awards, and being remixed into more than 60 versions - ranging from bad German techno to bluegrass.
More surprising still was the motley crew of musos who began to do cover versions of it. Kanye West was so enamoured of the song he rapped over it for his latest mix tape and got Peter, Björn and John to accompany him on the song when he played a show in Sweden. A Japanese singer, Shugo Tokumaru, covered the song for a podcast and it became one of the most played songs on Japanese radio. James Blunt has taken to covering it in concerts and even German singer Nena (of 99 Red Balloons fame) re-emerged to translate it into German as Ick Kann Nix Dafur for a film soundtrack.
What was it about this song from an otherwise unremarkable Swedish indie band that fostered such interest. The lyrics are robust enough - detailing a couple chatting each other up as a night in a bar comes to an end - and the melody line has an easy bounce to it, but it's over to professional whistler Linda Parker Hamilton for the real reason behind the song's success. "Young Folks has created more buzz around whistling than any other song in the last 50 years or since The Bridge on the River Kwai in 1957," she says.
The last time whistling troubled the charts must have been when German metallers Scorpions took their power ballad Winds Of Change to the top of the charts in 1990 - but the whistling on that song sounded very heavily treated by studio trickery. When playing live, I believe, the band used a synth sample to recreate the effect.
Bravely though, Peter, Björn and John insist on live whistling every time they perform. This may not seem a big deal. But it is. For proof, look at the YouTube footage of the band performing the song on Friday Night with Jonathan Ross. Half-way through, vocalist and whistler Peter Morén is really struggling.
This though is not the most interesting aspect of the Ross performance. Making a very rare live appearance with the band is the original female vocalist on Young Folks, Victoria Bergsman. The last time Bergsman was due on the Jonathan Ross show with her band, The Concretes, a few months previously, she had dramatically walked out of the band minutes before they were due to perform.
And that is how the song came about: knowing Bergsman was at a low ebb following her sudden departure from The Concretes, her old friends, Peter, Björn and John called around to her with a demo of Young Folks asking her to sing on it. "When they first played me the song, I just thought how brilliant it was," says Bergsman. "Our finished version turned out really well, but really, it hasn't anything to do with me. It's their song."
For many though, it's Bergsman's vocal performance, and not the whistling, that makes the song. Her oddly deadpan delivery is the perfect counterpoint to the chirpy whistling. Bergsman went on to release her own solo album, Open Fields under the name Taken By Trees. It is one of this year's most neglected but very best releases.
Bergsman doesn't tour much because of chronic stage fright, so the band first experimented with Morén doing both vocal parts, but that wasn't working so now they pre- arrange for a local female vocalist to join them on stage in whatever city they're playing in.
Either mashed up with Amy Winehouse's Rehab, rapped up by Kanye West or technoed out of all shape, Young Folks looks set to be the single of the year - for the second year running.
