Who is the undisputed queen of Pop in the present time? Have you ever wondered? Rolling Stone, a U.S.- based magazine devoted to music, liberal politics, and popular culture, has come up with an index of 16 solo female artists. It ranked the artists on the basis of six criteria including album and digital song sales, Hot 100 rankings, radio airplay, YouTube views, social media, concert grosses, industry awards and critics' ratings.

The competitors are (in alphabetical order): Adele, Christina Aguilera, Beyoncé, Kelly Clarkson, Miley Cyrus, Ke$ha, Lady Gaga, Nicki Minaj, Katy Perry, P!nk, Rihanna, Robyn, Shakira, Britney Spears, Taylor Swift and Carrie Underwood.

The time period covered for the selection procedure is from 2009 to mid-2011.

Below are the 16 glamorous pop stars according to their rankings:

Singer

Singer Lady Gaga arrives at an album signing event for her new release Born This Way at Best Buy in New York City May 23, 2011. REUTERS/Jessica Rinaldi
Music

Music recording artist Taylor Swift poses at the premiere of Easy A at the Grauman's Chinese theatre in Hollywood, California September 13, 2010. The movie opens in the U.S. on September 17. REUTERS/Mario Anzuoni
Singer

Singer Rihanna poses during an appearance on NBC's Today show in New York, May 27, 2011. REUTERS/Brendan McDermid
Singer

Singer Britney Spears performs at the MTV Video Music Awards in New York on September 7, 2000. Spears is nominated for awards in four categories, including Best Female Video. REUTERS/Jeff Christensen
Beyonce

Beyonce performs on the Pyramid stage on the last day of the Glastonbury Festival in Somerset June 26, 2011. REUTERS/Cathal McNaughton
Singer

Singer Katy Perry poses on arrival at the 53rd annual Grammy Awards in Los Angeles, California February 13, 2011. REUTERS/Danny Moloshok
Singer

Singer Pink arrives on the red carpet at the 52nd annual Grammy Awards in Los Angeles January 31, 2010. REUTERS/Mario Anzuoni
Miley

Miley Cyrus poses on arrival at the 53rd annual Grammy Awards in Los Angeles, California February 13, 2011. REUTERS/Danny Moloshok
Singer

Singer Ke$ha arrives at the 2011 Billboard Music Awards show in Las Vegas, May 22, 2011. REUTERS/Steve Marcus
Colombian

Colombian pop star Shakira performs during her concert at National stadium in San Jose April 10, 2011. Shakira's concert was part of the various activities organized for the inauguration of the new national stadium donated by the Government of China. REUTERS/Juan Carlos Ulate
Singer

Singer Carrie Underwood waves as she arrives at the 46th annual Academy of Country Music Awards in Las Vegas April 3, 2011. REUTERS/Sam Morris
Presenter

Presenter Nicki Minaj poses backstage at the 2011 MTV Movie Awards in Los Angeles, June 5, 2011. REUTERS/Danny Moloshok
Singer

Singer Kelly Clarkson, one of the featured Divas, arrives for the VH1 Divas show in New York September 17, 2009. REUTERS/Chip East
British

British singer Adele Adkins arrives to attend the BRIT music awards at the O2 Arena in London February 15, 2011. REUTERS/Toby Melville
Singer

Singer Christina Aguilera poses during a media event for the upcoming television series The Voice in Los Angeles March 15, 2011. Singers Aguilera, Blake Shelton, Cee Lo Green and Adam Levine are coaches for participants in the reality television singing competition, which premieres on NBC April 26. REUTERS/Mario Anzuoni
Swedish

Swedish singer Robyn performs at the Coachella Valley Music & Arts Festival in Indio, California April 15, 2011. REUTERS/Mike Blake