Rn'B is also Urban contemporary is a music radio format. The term was coined by the late New York DJ Frankie Crocker in the mid-1970s. Urban contemporary radio stations feature a playlist made up entirely of hip hop, R&B, pop, house, electronica such as dubstep and drum and bass (often with hip hop vocalists or rappers) and Caribbean music such as reggae, reggaeton, zouk, and sometimes Soca (In Toronto, London, New York City, Boston and Miami). Urban contemporary was developed through the characteristics of genres such as R&B and soul.[1] Virtually all Urban contemporary formatted radio stations are located in cities that have sizeable African-American populations, such as New York City, Atlanta, Chicago, Washington DC, Philadelphia, Detroit, Cincinnati, Dallas, Houston, Los Angeles, Baltimore, Memphis, New Orleans and Charlotte. The term "urban contemporary" is heavily associated with African-American music, particularly for Contemporary R&B in African-American contexts. For the Latinos, the music is more Latin urban, such as Reggaeton, Latin hip hop, or bachata. These stations focus primarily on marketing to African-Americans between the ages of 18 and 34.[citation needed] Their playlists are dominated by singles by top-selling hip hop and R&B performers. On occasion, an urban contemporary station will play classic soul songs from the '70s and early '80s to satisfy the earlier end of the genre. Most Urban formatted stations such as KJLH, KPRS, KMEL, KDAY, WRBP, UTN, and WVEE will play gospel music or urban contemporary gospel music on Sundays. Mainstream urban is a branch of urban contemporary, and rhythmic contemporary is also a branch. Since the 1990s, as urban contemporary hits have dominated the US pop charts, many adult contemporary stations have turned to playing some tracks popular on urban contemporary radio stations. Following periods of fluctuating success, urban music attained commercial dominance during the early 2000s, which featured massive crossover success on the Billboard charts by R&B and hip hop artists.[3] In 2004, all 12 songs that topped Billboard Hot 100 were African-American recording artists and accounted for 80% of the number-one R&B hits that year.[3] Along with Usher's streak of singles, Top 40 radio and both pop and R&B charts were topped by OutKast's "Hey Ya!", Snoop Dogg's "Drop It Like It's Hot", Terror Squad's "Lean Back", and Ciara's "Goodies".[3] Chris Molanphy of The Village Voice later remarked that "by the early 2000s, urban music was pop music."[3] Today, urban contemporary refers to music that can be described as a crossover of rap and contemporary R&B which in some instances may be accompanied with dance beats. Notable examples include: "I'm Real" by Jennifer Lopez and Ja Rule "Dilemma" by Nelly and Kelly Rowland "Crazy in Love" by Beyoncé Knowles and Jay-Z "Baby Boy" by Beyoncé Knowles and Sean Paul "Yeah!" by Usher, Lil Jon and Ludacris "Goodies" by Ciara and Petey Pablo "1 Thing" by Amerie "Single Ladies" by Beyoncé Knowles "Triumphant (Get 'Em)" by Mariah Carey It should be noted that R&B artists usually produce alternative versions of such collaborations that have rapping excluded. Such versions are produced for more conservative radio stations that refuse to play rap music.