With Lady Gaga locked in at No. 1 for a fourth week and only one song entering the top 10, Britney Spears makes the Billboard Hot 100's splashiest headlines, debuting at No. 20 with "Till the World Ends." Although she snaps a string of two consecutive No. 1 debuts ("3" and "Hold It Against Me"), a feat only she and Mariah Carey have managed, Spears logs the fifth-highest-debuting of her 25 Hot 100 entries. "World," the second single from "Femme Fatale," due March 29, arrives with 117,000 downloads sold, according to Nielsen SoundScan, after three days of availability. ("Hold," the set's lead track, launched at No. 1 seven weeks ago with 411,000 downloads after six days on sale).
"World," co-written by Ke$ha, concurrently starts at No. 68 on Radio Songs with 16.8 million out-of-the-box audience impressions on 145 stations, according to Nielsen BDS.