But six years after her last album, Lotus, fans were so desperate for new music that they made video montages that poked fun at her endless teasing and drip-feeding of details, which ultimately revealed nothing. But none of that matters now because she's back, armed with her new single Accelerate, which is out now, and album Liberation, which follows on June 15. It's Christina's eighth record, factoring in her Christmas album and Spanish language record Mi Reflejo.

Genie in a Bottle
Every pop superstar's career has to start somewhere and Christina's kickoff was better than most. A genuine phenomenon when released in 1999, demand was so high that the US import charted the week before its official UK release. Shifting 172,000 copies in that first seven days on sale, Genie in a Bottle spent two weeks at Number 1. It lands as her third biggest song with 716,000 copies sold, and 10.6 million streams.

Lady Marmalade
Collaborating has been key to Christina's success over the years, and some of her most enduring hits have been her team-ups with other huge artists. 2001's Lady Marmalade was a real turning point for Christina – while she'd been spotted out and about sporting a more outré look, this was the first time we'd seen Christina fully expressing herself and letting out her wild side. With Lil Kim, Pink and Mya on board, this was a guaranteed hit – another Number 1. On her rundown, it clocks in as her fourth biggest song overall, combining sales of 588,000 and 17.1m.

Dirrty
If Lady Marmalade was the starter, Dirrty was the main. Christina was pulling no punches – indeed, the video was set at a very rough boxing match – on this fantastically gritty Number 1 from 2002. The lead from her huge-selling sophomore album Stripped, Dirrty spent two weeks rubbing itself up against the Number 1 spot, and has scored 399,000 sales and 12.3m streams to land in Christina's all-time Top 5. Despite its success across Europe, Dirrty struggled in the US and stalled at Number 48, mainly due to lack of radio play which counts towards the Billboard Hot 100.

Moves Like Jagger
Now, a big one. Christina hadn't been in the Top 10 for a while when this insanely catchy track from a revitalised Maroon 5 came along in 2011. Christina's scene-stealing cameo helped Moves Like Jagger to million-selling status – but it couldn't lift it to Number 1. Yep, Moves Like Jagger spent an agonising SEVEN weeks at 2, beaten to the top by six different songs, including Example, Rihanna FT Calvin Harris, Pixie Lott and One Direction.

In fact, Moves Like Jagger is the second bestselling single in the history of the Official Singles Chart not to get to Number 1, beaten (again) by Wham’s Last Christmas. It was the second biggest selling single of 2011, behind Adele's Someone Like You, and is Christina's biggest song in the UK – 1.54 million sales and 26 million streams. However… while it is her top seller, it isn't her most streamed track.