No. 10, “Music of the Sun,” 593,000, 2005

No. 5, “A Girl Like Me,” 1,330,000, 2006

No. 2, “Good Girl Gone Bad,” 2,616,000, 2007

No. 106, “Good Girl Gone Bad: the Remixes,” 49,000, 2009

No. 4, “Rated R,” 943,000, 2009

No. 158, “Rated R: Remixed,” 13,000, 2010

All albums combined, Rihanna has sold 5,563,000 units in the U.S., according to SoundScan.
Hell, you can even add together the sales of Beyonce’s last two albums and they exceed Rihanna’s total.