Chart Beat

This Week in Billboard Chart History: In 2009, Lady Gaga Shuffled to No. 1 on the Hot 100 With 'Poker Face'

Lady Gaga
Martin Philbey/Redferns

Lady Gaga performs on stage at the Rod Laver Arena on May 26, 2009 in Melbourne, Australia.

Plus, remembering feats by ABBA, TLC & USA for Africa.

Your weekly recap celebrating significant milestones from more than seven decades of Billboard chart history.

April 8, 2006
A lot of good came out of Daniel Powter having a "Bad Day": his song, as featured on American Idol in 2006 as contestants' departure theme, rose to the top of the Billboard Hot 100.

April 9, 1977
After scoring six career-opening top 40 Billboard Hot 100 hits, ABBA led the list at last with "Dancing Queen."

April 10, 1999
20 years ago: TLC scored its third of four Billboard Hot 100 No. 1s, as "No Scrubs" reached No. 1.

April 11, 2009
10 years ago: "Poker Face" dealt Lady Gaga her second Billboard Hot 100 No. 1. Debut smash "Just Dance," featuring Colby O'Donis, had led for three weeks that January. She's since ruled again with "Born This Way" in 2011 and "Shallow," with Bradley Cooper, this March.

April 12, 1997
As the Lilith Fair era reigned, Jewel topped Billboard's Pop Songs radio airplay chart with "You Were Meant for Me." Follow-up "Foolish Games" would likewise lead the list in October 1997.

April 13, 1985
The landmark teaming of 43 artists, billed as USA for Africa, helped "We Are the World" reach the top of the Billboard Hot 100 for its first of four weeks at No. 1. More importantly, the song has reportedly helped raised more than $100 million for humanitarian aid in Africa and the U.S.

April 14, 2001
Janet Jackson jumped to her 10th and most recent Billboard Hot 100 No. 1 with "All for You."