The Shake It Off hitmaker is the highest-placed entertainer on the 2015 40 Under 40 list, coming in at six thanks to her strong stance against free streaming services.

Last year (14), the 25-year-old singer pulled her entire catalogue from Spotify because she wanted better compensation for the use of her music, while she famously forced Apple chiefs to backtrack over plans not to pay artists for their work during a trial of their new Apple Music app.

Her industry activism has landed her in the top 10 on the new Forbes countdown, just days after her efforts helped rocket her to the top of Vanity Fair's The Powers That Be 2015 list.

Swift sits behind the likes of WeWork entrepreneur Adam Neumann, Tesla boss J.B. Straubel and Uber CEO Ryan Graves, who are ranked first, second, and third, respectively, by Forbes editors.

Other celebrities to feature on the list include British comedian and U.S. TV host John Oliver at 10, actress and The Honest Company co-founder Jessica Alba at 15, and Ultimate Fighting Champion Ronda Rousey at 40.