Its data, published by Billboard magazine and compiled by Nielsen SoundScan, is based collectively on each single's weekly physical and digital sales, as well as airplay and streaming.
In total, thirteen acts topped the chart as either lead or featured artists, with six—Juicy J, John Legend, Iggy Azalea, Charli XCX, Magic!
Pharrell Williams' "Happy" was the longest-running number-one of the year, leading the chart for ten weeks; it subsequently topped the Billboard Year-End Hot 100.
[3] Azalea became the fourth solo female rapper to top the chart when "Fancy" reached number one in June, a feat previously achieved only by Lauryn Hill, Lil' Kim and Shawnna.
[6] In doing so, Swift became the first female artist in the history of the Hot 100, and tenth act overall, to replace herself at the top of the chart.