Singer Paulina Rubio poses in the press room during the 12th annual Latin GRAMMY Awards at the Mandalay Bay Resort & Casino on November 10, 2011 in Las Vegas, Nevada. (Photo by Ethan Miller/Getty Images)

Rapper Nicki Minaj onstage during the 2012 BET Awards at The Shrine Auditorium on July 1, 2012 in Los Angeles, California. (Photo by Christopher Polk/Getty Images For Polk)

Madonna poses in the press room during the 2013 Billboard Music Awards at the MGM Grand in Las Vegas, Nevada, May 19, 2013. (Photo by Robyn Beck/AFP Photo)

Rihanna performs live on stage at Allphones Arena on October 3, 2013 in Sydney, Australia. (Photo by Cameron Spencer/Getty Images)

Singer Fergie of the Black Eyed Peas arrives at the 54th Annual GRAMMY Awards held at Staples Center on February 12, 2012 in Los Angeles, California. (Photo by Jason Merritt/Getty Images)

Rita Ora attends the Capital Summertime Ball at Wembley Stadium on June 21, 2014 in London, England. (Photo by Tim P. Whitby/Getty Images)

Recording artist Selena Gomez performs onstage during 106.1 KISS FM's Jingle Ball 2013 at American Airlines Center on December 2, 2013 in Dallas, Texas. (Photo by Cooper Neill/Getty Images for Clear Channel)

Lady Gaga arrives at Roseland Ballroom on March 28, 2014 in New York City. (Photo by Theo Wargo/Getty Images)

Britney Spears during the first night of her two year Piece Of Me Concert residency at Planet Hollywood Hotel and Casino in Las Vegas, NV., 2013. (Photo by GoldenEye/London Entertainment/Splash News)

Miley Cyrus performs at the Air Canada Centre in Toronto, Ont. on Monday March 31, 2014. (Photo by Sun Media/Splash News)