Pharrell Williams proved it was his year to get lucky as he saw out 2013 with a third UK number one single.
The American singer/songwriter and producer knocked X Factor winner Sam Bailey's cover of Demi Lovato's Skyscraper into second place with aptly-named track Happy.
In April, the 40-year-old scored his first chart-topper of the year while providing soulful vocals on French dance duo Daft Punk's smash hit Get Lucky.
Just one month later he was back in first place, appearing alongside Robin Thicke and TI on Blurred Lines in one of 2013's most controversial tracks.
Happy, which is taken from the soundtrack to Despicable Me 2, made a surprise entry at number two last week before selling 107,000 copies over the last seven days to make it to the summit.
Pharrell's end of year solo success crowns a distinguished career which he began as one half of the Neptunes production duo, delivering the goods for the likes of Madonna, Beyonce, Britney Spears, Jay Z and Justin Timberlake.
The Star Trek fan has also gained critical acclaim but little top five chart traction with rock/funk/hip-hop project N.E.R.D.
He is now expected to release a second solo album early next year to follow 2006 debut In My Mind, which peaked at number seven in the charts.
Completing the singles top five, Swedish DJ Avicii saw Hey Brother climb two places to number three, while Jason Derulo's Trumpets and The Monster by Eminem and Rihanna both scaled four places into fourth and fifth respectively.
The week's sole new entry in the singles list was Beyonce's latest track, Drunk in Love featuring husband Jay Z, which debuted at number 29.
Meanwhile, it was a Take That face-off in the albums charts as Robbie Williams' Swings Both Ways kept bandmate Gary Barlow at bay to retain the crown.
Barlow's latest solo effort, Since I Saw You Last, sold 79,000 copies but proved no match for Robbie's big band effort, which shifted 91,000 to become the UK's 1000th number one album after debuting at the top last month.
Boyband heroes One Direction fell one place to number three with Midnight Memories, while Beyonce's self-titled album was fourth and Olly Murs' Right Place, Right Time was fifth as the pair switched positions.
With the country preparing for New Year's Eve celebrations, some of the year's best-loved tracks and albums crept back into the top 40.
Rizzle Kicks were up 48 places to number 31 with Skip To The Good Bit, Ylvis' The Fox climbed 25 to number 33, One Direction's Best Song Ever was up 34 to number 34 and The Vamps' Can We Dance made up 39 positions to number 35.
Robin Thicke's Blurred Lines (39), Jessie J's It's My Party (40) also returned, climbing 21 and 69 places respectively.
The album top 40 also saw Emeli Sande's record-breaking debut Our Version Of Events climb 12 places to 31.
Other records making a re-appearance were 1975's self-titled debut (up 21 spots to 32), Lorde's Pure Heroine (up 19 positions to 33), Rudimental's Home (up 12 to 34), Calvin Harris' 18 Months (up 27 to 35) and Haim's Days Are Gone (up eight to 40).