With a series of single words, she provided a soundtrack for the last thirty years: Holiday; Borderline; Cherish; Vogue; Frozen; Music; Sorry; Celebration. She defied convention, defined success, remains respected and popular, yet the 53 year old woman who held court last night in front of thousands of revellers in London's Hyde Park - and who is on a 90-date tour - has not had a Number 1 single in the UK since 2008.
Without fail, since 1983's self-entitled Madonna album, every first single released from a new Madonna album has reached the UK Top 5. Until now. Give Me All Your Luvin' reached the unremarkable position of number 37. The follow up single from the current MDNA album, Girl Gone Wild, peaked at an incongruous number 73.
Madonna isn't alone in this trend. Kylie's last single (from an as yet unreleased album) bombed at number 31. None of her last three singles from 2010's Aphrodite made the UK top ten. Even Beyoncé has not had a solo Number 1 single in the UK since 2008, despite a string of powerful songs released since then (Single Ladies (Put a Ring on It), Halo, Run the World (Girls), Best Thing I Never Had). Britney's last UK Number 1 was 2004's Everytime. None of her last three standalone albums nor two compilation albums have yielded any Number 1 singles. Mariah Carey's last UK Number 1 was the 2000 Phil Collins' cover, Against All Odds, sung with Westlife - which fact makes me sad for Britain more than a phone-hacking, expenses-fiddling, LIBOR-fixing G4S chief executive ever could). As for other top-selling female artists: P!nk, Shakira, Céline Dion - not even a sniff of a Number 1 since 2008 despite record releases, huge name recognition, fan-bases and record companies behind them.
What's going on here? Is this part of a wider trend of artists no longer needing to (or being able to) sell singles to make money and maintain popularity? Is it simply because of a lack in quality of songwriting or freshness of sound? Has illegal downloading, Spotify and YouTube really killed the single sales market in the last few years?
One female artist bucks this trend, and spectacularly so. Since 2008 (the date of Madonna's last Number 1), Rihanna, when you include collaborations, has clocked up no fewer than six number 1s and 15 other Top 40 hits. Industry insiders may complain about her ubiquity but whether it be a loyal fanbase, good songwriting, on-the-money marketing or a combination of the above, Rihanna's brand of global, urban, sex-infused, youthful R&B/pop has made her one of the best-selling artists of all time. A remarkable achievement in just seven years since she burst onto the music scene, and no small part in Universal Music Group's increased revenues in 2012, against market trends.
Arguably, Madonna no longer needs to sell singles. Like Sir Elton John, Cher, Sir Paul McCartney - after a certain age, artists have enough of a back catalogue to tour forever and sell tickets - these artists' new music (when there is some), by and large, is unloved by all but the most hardcore fans. They're in the graveyard of popular music - wheeled out for Olympics opening ceremonies and Vegas shows - but by no means is it a shameful place to be, not least because it is so lucrative.
The lack of Number 1s from established artists is not necessarily bad for the music industry. Bar the X-Factor winners (and losers), the last few years has seen a marked increase in new, independent British acts hitting the UK Number 1 spot, like Tinie Tempah, Pixie Lott, Dizzee Rascal, Florence & The Machine, Adele, Jessie J, Example, Professor Green and Rita Ora.
Ultimately, what each of these artists have - as with Rihanna - is that youthful energy, the verve, the being-of-the-moment. Madonna had it - by the bucketload - for 25 years.
Unfortunately, Madonna's latest attempts (with Nicki Minaj and M.I.A.) seemed as cringeworthy as those Primrose Hill mothers desperate to be 'friends' with their daughters. Whatever the rights and wrongs are of us expecting women of a certain age to act in a certain way - the fact remains, trying too hard just doesn't sell records. It's just not cool.
Which brings us to the question: what makes a good Number 1? As a lay listener and consumer, probably a combination of factors: uniqueness; song quality; "nowness"; and sex appeal. A song that excels in at least one of these areas will likely do well. More than one and you may even be guaranteed a hit. Even when you've been written off as a serious artist (see J-Lo before she surprised everyone with the unique, quality, zeitgeisty, sexy On the Floor), there's still a chance for pop redemption with the right (sadly not so easy) recipe. As it is, Madonna has let us and herself down with her latest singles - they're not unique, nor simply that good. They sound "of the moment" but only in a forced way. And for some reason, the current look just doesn't feel sexy (unlike say Tina Turner or Cher at similar ages). Once you've put your fanny pics on a coffee table book, there aren't many further boundaries you can push, sex-wise. Compare her latest offerings with Rihanna (forgetting the age gap, if you can) and the difference in all four of the hit-making factors is clear.
Despite this, Madonna remains relevant, controversial, headline-grabbing, able to sell tickets and physically and mentally fit for long world tours. Few artists in the world can say the same. She is an inspiration without an ideology and a re inventor without an invention. As it stands though, she is a pop superstar, on tour, without a current hit. It's not the Vegas graveyard for her though. If there's one thing we can be pretty sure of, it's that she'll be dancing in her knickers and duetting with her rapper grandchildren when she's 88. And maybe that will be unique and new enough to make Number 1. Here's hoping.