This past week, the music streaming service Spotify reported that its personalized playlist, “Discover Weekly,” has surpassed 40 million followers since the company launched it last July.

With 89 million users, this means that nearly half of Spotify’s users actively listen to their Discover Weekly playlist. The playlist has found so much success with its users because its weekly updates tend to actually match listeners’ tastes. Each week, Spotify takes any given user’s music searches from the previous week and compiles a 30 song playlist based on searches and listens for each individual user. Spotify reports that on average, a user will save 1 in 10 songs from “Discover Weekly” to one of his playlists weekly.

Spotify also reports that Discover Weekly has found the most success with the 25 to 34 demographic, likely because this age group has less time to find new music. Discover Weekly expedites their search process because unlike other streaming services, such as Apple Music and Tidal, Spotify involves itself in cultivating its customers’ musical tastes.

Streaming has become more popular because it panders to the increasingly mobile culture by not requiring the listener to buy, download, or own any music. In fact, that there is now speculation that Apple is considering shutting down iTunes, its downloading service, in favor of Apple Music, its streaming service.

As streaming overtakes traditional ways of acquiring music, artists and services alike will have to find new ways to meet listener needs. Spotify’s “Discover Weekly” playlist represents an example of a brand reaching out to its customers and making its service personalized to each user’s wants.