10. Shakira ($20 million)

MADRID, SPAIN - DECEMBER 09: Singer Shakira performs on stage during "40 Principales Awards" 2011 at Palacio de los Deportes on December 9, 2011 in Madrid, Spain. (Photo by Carlos Alvarez/Getty Images)

9. Madonna ($30 million)

Madonna (Lluis Gene/AFP/GettyImages)

US singer Madonna performs during her "Sticky & Sweet Tour" concert on July 21, 2009 at the Olympic Stadium "Lluis Companys" in Barcelona. AFP PHOTO/ LLUIS GENE (Photo credit should read LLUIS GENE/AFP/Getty Images)

8. Sade ($33 million)

Singer/songwriter Sade performs at the MGM Grand Garden Arena September 3, 2011 in Las Vegas, Nevada. (Ethan Miller/Getty Images)

7. Adele ($35 million)

Adele (FREDERIC J. BROWN/AFP/Getty Images)

Musician Adele poses with her six trophies at the 54th Grammy Awards in Los Angeles, California, February 12, 2012. AFP PHOTO/ FREDERIC J. BROWN (Photo credit should read FREDERIC J. BROWN/AFP/Getty Images)

6. Beyoncé ($40 million)

Jim McIsaac/Getty Images Sport

5. Katy Perry ($ 45 million)

(Mark Thompson/Getty Images)

4. Lady Gaga ($ 52 million)

(Tim Mosenfelder/Getty Images)

3. Rihanna ($53 million)

Simone Joyner/Getty Images Entertainment

2. Taylor Swift ( $57 million)

(Isaac Brekken/Getty Images)

1. Britney Spears (58 million)

(Kevin Winter/Getty Images)