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The Rhythmic chart (also called Rhythmic Airplay, Rhythmic Top 40 or CHR/Rhythmic) is an airplay chart published weekly by Billboard magazine. The chart tracks and measures the airplay of songs played on rhythmic radios stations, whose playlist includes mostly hit-driven R&B/hip-hop, rhythmic pop, and some dance tracks. Arbitron sometimes refers to the format as rhythmic contemporary hit radio.
Billboard magazine first took notice of the newly emerged genre on February 15, 1987, when it launched the first crossover chart. The first number one on that chart was "Looking for a New Love" by Jody Watley, and it originally consisted of thirty titles and eighteen stations reporting to the panel. By December 1990, Billboard eliminated the chart because more top 40 and R&B stations were becoming identical with the rhythmic-heavy playlist also being played at the crossover stations at the time.
Billboard revived the chart in October 1992 as Top 40/Rhythm-Crossover (along with Top 40/Mainstream), with the first number one being "End of the Road" by Boyz II Men. On June 25, 1997, it was renamed to Rhythmic Top 40 as a way to distinguish stations that continued to play a broad based rhythmic mix from those whose mix leaned heavily toward R&B and hip-hop. It was changed to Rhythmic Airplay in the February 7, 2004, issue and shortened to Rhythmic on July 12, 2008.
Chart criteria 
There are forty positions on this chart and it is solely based on radio airplay. 66 rhythmic radio stations are electronically monitored 24 hours a day, seven days a week by Nielsen Broadcast Data Systems. Songs are ranked based on the number of plays that each song received during that week.
Songs receiving the greatest growth will receive a "bullet", although there are tracks that will also get bullets if the loss in detections doesn't exceed the percentage of downtime from a monitored station. "Airpower" awards are issued to songs that appear on the top 20 of both the airplay and audience chart for the first time, while the "greatest gainer" award is given to song with the largest increase in detections. A song with six or more spins in its first week is awarded an "airplay add". If a song is tied for the most spins in the same week, the one with the biggest increase that previous week will rank higher, but if both songs show the same amount of spins regardless of detection the song that is being played at more stations is ranked higher. Songs that fall below the top 15 and have been on the chart after 20 weeks are removed.
Records and achievements 
Most weeks at number one 
- "I'll Make Love to You" — Boyz II Men (1994)
- "Fantasy" — Mariah Carey (1995)
- "Lollipop" — Lil Wayne featuring Static Major (2008)
Artists with most number-one singles 
- 11 - Usher
- 9 - Rihanna
- 8 - 50 Cent, Lil Wayne, Nelly
- 7 - Beyoncé, Mariah Carey, T-Pain
- 6 - Drake, Kanye West, Ludacris
See also 
- Dance/Mix Show Airplay
- Mainstream Top 40 (Pop Songs)
- List of artists who reached number one on the U.S. Rhythmic chart
- Current BDS Rhythmic Top 40 chart (updated weekly)