During this period, Gaga was riding high, and many claimed that she had replaced Rihanna as pop music's it girl due to the mediocre success of Rated R.
However, since the both have released three albums, and Rih has outsold Gaga in singles and in album sales since. Gaga's last #1 song was in 2011 with the crazy hyped BTW era, while Rih's was just last year. Why?
