Much like magazines and newspapers, streaming music outfits largely measure success by the number of paying subscribers on the roster. It is why, when a major player like Spotify announces it now has more than 40 million paid subscribers, people take notice.

Spotify co-founder and CEO Daniel Ek disclosed the milestone on Twitter Tuesday morning.

At last check (this past March), Spotify had 30 million paying subscribers which means it added 10 million premium users in less than six months. A month later, the company said it had more than 100 million active monthly users, a significant figure considering Spotify is one of just a handful of streaming music services that still offers a free, ad-supported tier.

How does that compare to the competition?

During its iPhone 7 media event last week, Apple said it now has 17 million paying Apple Music subscribers - up from just 13 million in April (Apple Music doesn't offer a free tier). The Tidal ship, captained by music mogul Jay Z, continues to take on water as the company lost nearly twice as much money in 2015 as it did the year before.

Jay Z back in April sued Tidal's former owners over claims that it lied about how many subscribers it had during the negotiation process. After the sale, new management realized that the true subscriber count was well below the 540,000 the previous owners claimed. As of this past March, Tidal had three million subscribers.

Rhapsody, which acquired online music pioneer Napster in 2011, recently decided to revert back to the controversial name. As of late last year, the company had nearly 3.5 million paying subscribers; it's unclear how many premium members it has added in 2016.

Internet radio pioneer Pandora, which is expected to launch an on-demand subscription service any day now, could work its way onto the podium after acquiring Rdio last November for $75 million.

In related news, Spotify's chief revenue officer Jeff Levick announced on Medium that he is leaving the company after five years on the job.

Levick had nothing but good things to say about Spotify in his farewell speech, citing his love for the company, the product, the teams and the hyper growth they've experienced over the past several years. All of the hard work has certainly paid off but as Levick noted, working hard is hard work.

When questioning whether or not he was up for another grueling five years of global travel in which he would miss more of his kids' various activities and continue to put the burden of raising them on his wife, it started to become clear that maybe a change was in order.

Spotify told Re/code that the ad sales team that used to report to Levick will now answer to chief financial officer Barry McCarthy while the team that manages Spotify's subscriber business will now report directly to Ek.

Tidal image courtesy Kevin Mazur, Roc Nation. Levick photo via Business Insider