The chart from 23 June 2013 had 18.
Why has the featured artist become such a staple of popular music in less than a decade?
To some extent it has a lot to do with the changing role and perception of the music producer.
Traditionally, the name of a music producer would only be known by those who needed to, or those who sought them out.
Sam Phillips, Berry Gordy and J Dillo garnered reputations for being outstanding producers, but they never came close to the fame and adulation they would probably receive today.
In recent years, the music producer has moved out of the shadows and become acknowledged as an artist in their own right, with producers like Timbaland, Mark Ronson and will.i.am recording their own albums featuring the talents of other established acts.
Perhaps this marks a necessary development in music publishing in which the key contributors to a record are explicitly acknowledged and not just given a cursory mention in the sleeve notes.
This of course only accounts for a handful of artists – and does not take into account how this phenomenon went from being an oddity to a norm.
Although collaboration between different artists has been present since the earliest days of recorded music, it was hip hop labels in the 80s and 90s that expanded the concept as means to give much-needed exposure to emerging artists by associating them with established acts.
It became symbolic of a kind of endorsement that fans could trust and use to seek out new music.
With hip hop moving from the sidelines to being a central force in global popular culture, it probably comes as little surprise that the idea of collaboration as a form of endorsement should be so widely embraced.
With a market that is increasingly saturated and stratified, a well-chosen collaborations can be a good way for artists to gain further exposure and generate an interest in their work from fans whose radars they haven't previously registered.
Daft Punk's recent collaboration with Pharrell Williams and Nile Rodgers on their hit Get Lucky exposed the French duo to a level of international success that they had never experienced before, reaching number one in the UK and America, and selling over a million copies.
It is arguable that the endorsement from Williams opened Daft Punk up to a larger audience than at any point previous.
Sometimes collaborations can come from a shared artistic vision, or a mutual admiration between performers who seek to bring their imaginative and creative powers together to create something of genuine intrigue.
When Nick Cave and the Bad Seeds recorded their album Murder Ballads, the band collaborated with an intriguing mix of artists from PJ Harvey to Kylie Minogue – the result was something that none of the artists involved could have expected going into the project.
In the 90s, the soundtracks to the films Judgement Night and Spawn created collaborations between acts from different genres with the express intention of sparking something creative and innovative – some of these collaborations worked, many of them didn't. Taking such risks, however, can only be applauded.
Beyond the utopian vision of artists collaborating in the spirit of creativity, there is an argument that the coupling of two or more artists is merely a cynical ploy by record companies to shift more units and get fans to part with even more money.
When will.i.am roped in the vocal talents of Britney Spears for his track Scream & Shout It, her voice was soaked in AutoTune, she spoke in a hammy German accent, and for some unfathomable reason she seemed to be calling for “All eyes on arse”. It was the star's name rather than her contribution that counted.
Where it used to be a method of exposing new audiences to established audiences, the collaboration between two or more major artists is no longer special and whiffs of cashing in.
If the trend continues to increase at the same trend as it has over the last decade, it is likely that the top 40 in 2023 will be composed entirely of collaborations – whether this is a good or bad thing is certainly open for debate.