Devotees of singer Katy Perry spend more than £1,600 a year on their idol, more than any other fan group, new research has found.
British fans of the pop star, known as KatyCats, hand over an average of £1,627 to buy her merchandise and music, and attend her shows.
Fans of rapper Kanye West spend an average of £1,563 and Directioners - devotees of boyband One Direction - spend £1,239.
Rihanna's so-called Navy of loyalists, and the Beyhive - fans of Beyonce - fork out £1,100 and £1,087 respectively.
The Battle of the Fan research, carried out by Barclaycard, compared the amount of money spent by self-identified "big fans" who have purchased at least three albums or singles by their chosen act, be it Beyonce, Florence & the Machine, Kanye West, Katy Perry, Lady Gaga, One Direction, Rihanna, the Rolling Stones, Take That, Taylor Swift, The Beatles or The Who.
The research compared how much they spent on concert and festival tickets, travel to shows, food and drink at shows, music and merchandise including clothing, perfume, programmes and make-up.
Fans of the Stones, who spend more than £150 on each concert ticket, dish out £907.01 a year. Lady Gaga's devotees, known as Little Monsters, spend £945.88 and Taylor Swift's fans spend £748.95.
Katy Perry recently became the most popular person on Twitter, with 90.2 million followers, ahead of Swift, Justin Bieber and President Barack Obama.
The study found that KatyCats post about their idol more than any other fan group, writing about Perry twice a week on Facebook, Twitter and Instagram, as well as sharing her posts and writing her messages twice a week.