For many years, a song had to be commercially available as a single to be considered for any of the "Billboard" charts. At the time, instead of using Nielsen SoundScan or Nielsen Broadcast Data Systems (BDS), "Billboard" obtained its data from manual reports filled out by radio stations and stores. According to the 50th-anniversary issue of "Billboard", prior to the official implementation of SoundScan tracking in November 1991, many radio stations and retail stores removed songs from their manual reports after the associated record labels stopped promoting a particular single. Thus, songs fell quickly after peaking and had shorter chart lives. In 1990, the country singles chart was the first chart to use SoundScan and BDS. They were followed by the Hot 100 and the R&B chart in 1991. Today, all of the "Billboard" charts use this technology.