Guess who is the top pop artist of the last 20 years? Tue-09-Oct-12 10:11 Share this By Jay-Jay FeeneyRIHANNA is stoked to be announced as Billboard.com’s top pop artist of the last 20 years.She tweeted: "Billboard crowned me #1 top 40 artist of the decade just 7 years into this!!... HistoRIH."Pink was second and Britney Spears third, Kelly Clarkson fourth and Mariah carey fifth. You May Also Like Rihanna and Drake’s PDA at the MTV Movie awards! See Riri and Eminem perform The Monster at the MTV Movie Awards Rihanna gets her knickers off again Become a fan of The Edge on Facebook and on Twitter .