NEW YORK – Bruno Mars returned to the No. 1 slot on the Billboard Hot 100 singles chart Thursday, ending Britney Spears' one-week reign.

Mars' "Grenade" logged a third nonconsecutive week at the top, having alternated between Nos. 1 and 2 over the past six weeks. Spears' "Hold It Against Me" tumbled to No. 6, as a hefty 55% slide in download sales more than offset a gain in radio airplay.

Katy Perry's former No. 1 "Firework" rose one to No. 2, rapper Wiz Khalifa's "Black and Yellow" jumped two to No. 3, Enrique Iglesias' "Tonight (I'm Lovin' You)" rose two to No. 4, and Rihanna's "What's My Name?" slipped one to No. 5.

Kesha's "We R Who We R" held at No. 7, Pink's "Raise Your Glass" at No. 8, and the Black Eyed Peas' "The Time (Dirty Bit)" at No. 9. Singer/rapper Pitbull's "Hey Baby (Drop It to the Floor)" jumped 10 places to No. 10.

At No. 79, Zac Brown Band's "Colder Weather" led a list of three songs new to the Hot 100. James Blunt entered at No. 94 with "Stay the Night," and alternative/punk band Yellowcard took the last slot with "For You, and Your Denial."

Justin Bieber's "Never Say Never," featuring Jaden Smith, re-entered at No. 85 after peaking at No. 33 during the summer. The song is being reworked to radio as an accompanying single to Bieber's 3D documentary concert film of the same name opening in theaters February 11.