High Quality Content by WIKIPEDIA articles! The Billboard Hot 100 is a chart that ranks the best-performing singles of the United States. Published by Billboard magazine, the data are compiled by Nielsen SoundScan based collectively on each single`s weekly physical and digital sales, and airplay. In 2006, there were 18 singles that topped the chart, the most number-ones in a chart year since 1991. Although 19 singles claimed the top position in the 52 issues of the magazine, singer Mariah Carey`s "Don`t Forget About Us" started its peak position in 2005 and is thus excluded.