Flooding the Zone – by Damon Krukowski:

Summing the number of artists listed in these seven categories, we get a total of 156,700. Not exactly the same as the 165,000 “artists who have released at least ten songs all-time and average at least 10,000 monthly listeners,” but close. (Asking Spotify to be precise with numbers seems to be unrealistic.) Close enough that perhaps it’s a fair assumption these two figures are related – and the seven categories are subdivisions of the 165,000 total “professional” accounts.

Source: Mark Hurst