Rounding out the Hot 100's top five, Katy Perry's former four-week No. 1 "Dark Horse," featuring Juicy J, holds at No. 5; follow-up "Birthday," meanwhile, jumps 29-25, led by its 34-22 vault on Radio Songs (46 million, up 20 percent) and No. 42 debut on Digital Songs (38 million, up 20 percent).