Black Americans have performed a disproportionate percentage of hit records since at least the 60s. In some other fields (Jews in film production, perhaps) some other ethnic groups do well.

Between late '63 and '65 black-performed music was so popular that Billboard did away with its separate R&B chart and kept track of black-oriented and non-black -oriented records on the same pop chart. Billboard later brought back the R&B chart as the Soul chart.