I looked over some of the 2009 charts. sweet dreams gets stuck and #11 for way too long, never gets on the top 10.
Oh Then idk. But I really think the Top 3 is Gaga / Katy / Beyonce though. The other possible contestants would be Britney or Rihanna, I think? Rihanna's & Britey's singles weren't that huge though so yeah.