"Firework" is Perry's fourth overall Hot 100 No. 1, as she also led the list for seven weeks in the summer of 2008 with "I Kissed a Girl," her first chart entry.
"Firework's" ascension to No. 1 means that six different songs in the past six weeks have claimed the top Hot 100 ranking, extending a turnover ratio not seen in more than 20 years.
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"Firework" sizzles at the top of Digital Songs for a second week with 212,000 downloads (down 9%), according to Nielsen SoundScan, while ranking as the week's top Airplay Gainer with a 12-8 lift on Radio Songs, up 25% to 83.3 million listener impressions, according to Nielsen BDS.
Last week's No. 1, P!nk's "Raise Your Glass," drops to No. 2, while Rihanna continues to climb back up the list (5-3) with her former chart-topper "What's My Name?," featuring Drake.
The Black Eyed Peas improve 9-4 with "The Time (Dirty Bit)" as the title moves into the runner-up slot on Digital Songs with 198,000 (up 10%). Their new album "The Beginning" starts at No. 6 on the Billboard 200, with 119,000.
Boyle Back to No. 1 on Billboard 200, Peas Begin at No. 6
Bruno Mars continues his upward trajectory with "Grenade" (10-5), while his "Just the Way You Are" slips 4-7. In between Mars's two tracks is Rihanna's "Only Girl (In the World)" (3-6).
Ke$ha stumbles 6-8 with "We R Who We R", Nelly falls 8-9 with "Just a Dream" and Trey Songz comes back into the top 10 with "Bottoms Up," featuring Nicki Minaj (11-10). The title has now spent seven weeks in the top 10.
"Glee" contributes to the Hot 100's Digital Gainer and Hot Shot Debut awards, as the cast's cover of Florence and the Machine's "Dog Days Are Over" is the top new entry at No. 22, selling 98,000 (No. 8 on Digital Songs). The song is one of five new entries by the "Glee" Cast this week.
Meanwhile, Florence and the Machine's original recording jumps 58-21 on the Hot 100 and 40-11 on Digital Songs, matching its previous best peak on the former list and achieving a new peak rank on the latter, moving 90,000 downloads (up 121%). The song reached its previous best rank following the band's head-turning performance on the MTV Music Video Awards in September.
The holiday season is in full swing, as the chart hosts its first two seasonal entries, both by top-selling alternative bands. Coldplay opens at No. 25 on the Hot 100 and No. 12 on Digital Songs (90,000) with "Christmas Lights," while topping the Holiday Digital Songs chart with the track.
The Killers enter at No. 79 on the big chart and No. 43 on the sales list (34,000) with "Boots." The band has released a holiday single each year since 2006, with its first offering, "A Great Big Sled," having been the only one to have previously charted on the Hot 100 (No. 54 peak).