History[edit]
Radio airplay has always been one of the component charts of the Hot 100. Prior to the establishment of the Hot 100, Billboard published a radio airplay chart, a singles sales chart and a jukebox play chart, the last of which was discontinued in 1959 as jukeboxes lost their popularity. During the 1960s and 1970s, Billboard continued to collect airplay data as a component of the Hot 100 but did not make the chart public.[3]
The airplay-only chart debuted as a 30-position chart on October 20, 1984, and was expanded to 40 positions on May 31, 1986.[4] Rankings were based on playlists received by a panel of Top 40 radio stations. On December 8, 1990, Billboard introduced the 75-position Top 40 Radio Monitor chart positions, which ranked songs measured by the number of spins each song on monitored radio stations and the ratings for those stations when the songs were being played based on Nielsen BDS technology.[5] The BDS-measured Top 40 Radio Monitor chart became the official airplay-component of the Hot 100 on November 30, 1991.[6]
Use in media[edit]
On November 30, 1991, after 21 years of using the Billboard Hot 100 as their source, American Top 40 started using this chart, which at the time was called the Top 40 Radio Monitor. This relationship ended in January 1993, as American Top 40 switched to the Billboard Mainstream Top 40 chart. The ongoing splintering of Top 40 radio in the early 1990s led stations to lean into specific formats, meaning that practically no station would play the wide array of genres that typically composed each weekly Hot 100 chart.