The Recording Industry Association of America (RIAA) has recognized R. Kelly as one of the best-selling music artists in the United States with 40 million albums sold as well as only the fifth black artist to crack the top 50 of the same list. In March 2011, R. Kelly was named the most successful R&B artist of the last 25 years by Billboard. Kelly has released 12 solo studio albums, and sold over 60 million albums and 15 million singles worldwide, making him the most successful R&B male artist of the 1990s. He has been credited for helping redefine R&B and hip hop, earning the nicknames "King of R&B" and "King of Pop-Soul". He is listed by Billboard as the most successful R&B/Hip Hop artist of the past 25 years (1985-2010) and also the most successful R&B artist in history. Throughout his career, Kelly has won numerous awards, including a Guinness World Records as well as countless other awards like Grammy, BET, Soul Train, Billboard, NAACP, and American Music Awards.