With explosive sales in their first week of digital release, new tunes by R&B singer Rihanna and rap group Shop Boyz rocketed to the top two spots on the Billboard Hot 100 singles chart Thursday.

Rihanna’s “Umbrella” jumped 41 places to No. 1 with 277,000 digital sales, the highest debut week sum since Nielsen SoundScan began tracking downloads in 2003. Meanwhile, Shop Boyz’ “Party Like a Rockstar” flew 50 places to No. 2 thanks to sales of 173,000 digital downloads.

For Rihanna, this is the second Hot 100 chart-topper of her young career, following “SOS” in 2006. As for “Party Like a Rockstar,” its digital arrival results in a steep decline for a similarly named but musically different cut, “Do It Just Like a Rockstar” by Freak Nasty featuring Crazy Mike. That song, which has been available digitally and was mistakenly purchased by many consumers thinking it was the Shop Boyz track, plummeted off the chart from No. 45 after a 62% drop in sales.

Last week’s Hot 100 No. 1, Maroon 5’s “Makes Me Wonder,” slipped to No. 3 this week. T-Pain’s “Buy U a Drank (Shawty Snappin’)” featuring Yung Joc was down two to No. 4, while Daughtry’s “Home” inched up one to No. 5.

Justin Timberlake’s “Summer Love” jumped three to No. 6, followed by Avril Lavigne’s “Girlfriend,” which fell four to No. 7. Fergie’s “Big Girls Don’t Cry” rose 13 top No. 8, giving the Black Eyed Peas vocalist her fourth top 10 hit from her 2006 solo album, “The Dutchess.”

Kelly Clarkson’s “Never Again” rebounded eight to No. 9 after her appearance last week on the “American Idol” finale, and Huey’s “Pop, Lock & Drop It” rounded out the top 10, slipping from No. 8.

Unsurprisingly, “Idol” winner Jordin Sparks boasted the Hot 100’s top debut with “This Is My Now” at No. 15. At 74,5000 downloads, it’s the lowest first-week sales total for an “Idol” coronation song ever, although this year’s release is the first to be digital only, accompanied by a multi-track EP. “Idol” runner-up Blake Lewis debuted at No. 18 with his version of Bon Jovi’s “You Give Love a Bad Name.”

Also new to the Hot 100 this week were T.I.’s “Big Things Poppin’ (Do It)” at No. 30, the reunited Smashing Pumpkins’ “Tarantula” at No. 54 and Gwen Stefani’s “4 in the Morning” at No. 76.
<B>Source</B>: Reuters