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This week, there is again a significant phenomenon on the Hot 100. As Bruno Mars' "Grenade" reclaims No. 1 from Katy Perry's "Firework," all the titles in this week's top five are current or former No. 1s.
Prior to the past three weeks, the last time five current or former leaders locked up the top five was the week of July 19, 2008. Two of this week's top five artists, Perry and Rihanna, occupied that top five, as well:
Long Island, New York
Thanks Jeff, as several readers have written in asking when this coincidence had last occurred.
The streak may be broken next week. While Britney Spears' "Hold It Against Me" is expected to launch at No. 1, new tracks by Kanye West and Jay-Z ("H*A*M") and Avril Lavigne ("What the Hell") each have a chance to storm the top five if their digital sales are strong enough.
As of this posting, the songs rank at Nos. 1, 2 and 3 (to paraphrase Spears' last No. 1) in the iTunes Store.