The Bubbling Under Hot 100 Singles
is a chart published weekly by Billboard
magazine in the United States. It lists the top 25 singles below number 100 that have not yet charted on the Billboard Hot 100
. Sometimes, however, singles halt their progress on this chart, and never appear on the Hot 100. The chart initially had 15 positions (during 1959–1960), but expanded to as many as 35 during the 1960s, particularly during years when over 1,000 singles made the Hot 100 chart. From 1974 to 1985, the chart consisted of 10 positions. Since 1992, the Bubbling Under chart has listed 25 positions.
The Bubbling Under chart first appeared in Billboard'
s June 1, 1959 issue. It continued until August 24, 1985, when it was discontinued. (Whitburn notes that during its original run, for unknown reasons the weekly chart was not issued on four occasions -- three of them in 1974, and one in 1978.) The Bubbling Under chart re-appeared without fanfare in the December 5, 1992 issue, and continues to the present day.
Several reference books on the history of the Billboard
"Bubbling Under" charts have been published by Joel Whitburn
's company. The latest book (from 2005) was Bubbling Under The Billboard Hot 100: 1959-2004
(ISBN 0-89820-162-4). Whitburn's most recent book Top Pop Singles, 12th Edition
(ISBN 0-89820-180-2), which covers all Hot 100 chart hits from 1955 through 2008, now includes all Bubbling Under entries also.