Billboard's Hot 100 chart has been in existence for five decades. Today, Katy Perry has become the first artist ever to spend an entire year in the top 10. Her dominance started with "California Gurls" and was kept alive with hits like "Teenage Dream", "Firework", and most recently "E.T." 

Before the pop star broke the 1-year mark, the longest any artist had spent in the top 10 was 48 weeks, achieved by Ace Of Base in the 90's. Katy's 2010 album Teenage Dream has sold almost 1, 451,000. Not bad, Ms. Perry.