US Modern Rock

Alternative Songs (also called Alternative and formerly known as Modern Rock Tracks and Hot Modern Rock Tracks) is a music chart in the United States that has appeared in Billboard magazine since September 10, 1988. It lists the 40 most-played songs on modern rock radio stations, most of which are alternative rock songs. The chart was introduced as a companion to the Mainstream Rock Tracks chart and its creation was prompted by the explosion of alternative music on American radio in the late 1980s.

The chart is based solely on radio airplay. As of 2012, approximately 80 radio stations are electronically monitored 24 hours a day, seven days a week by Nielsen Broadcast Data Systems. Songs are ranked by a calculation of the total number of spins per week with its "audience impression", which is based upon exact times of airplay and each station's Arbitron listener data. The chart had 30 positions when it was introduced in September 1988, and was expanded to 40 positions on September 10, 1994.

Many rock artists do not release commercial singles in the United States. Several popular songs which were not released as commercial singles did not qualify for the Hot 100 before December 1998, but performed very well on the Modern Rock Tracks chart.

During the first several years of the chart, it regularly featured music that did not receive commercial radio airplay anywhere but on a few modern rock radio stations. This included many electronic and post-punk artists. Gradually, as alternative rock became more "mainstream" (particularly spearheaded by the grunge explosion in the early 1990s), the Modern Rock Tracks and Mainstream Rock Tracks charts began featuring more of the same songs. Today, the Alternative chart favors more alternative rock, indie rock, and punk rock bands while the Mainstream Rock chart favors more hard rock, post-grunge and heavy metal.

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