Gwen hits: Rich Girl, Don't Speak, What You Waiting For?, Hollaback Girl, It's My Life, Hella Good, Underneath It All, The Sweet Escape, Hey Baby, Just A Girl, Cool, Luxurious, Wind It Up, Simple Kind Of Life etc.
Xtina hits: Genie In A Bottle, What A Girl Wants, Come On Over, Say Something, Candyman, Moves Like Jagger, Hurt, Ain't No Other Man, Beautiful, Dirrty, Fighter, Lady Marmalade, etc.
Which 'The Voice' judge ad pop icon has had the most iconic career?
Latest album first week sales:
Xtina (2012): 73,000
Gwen (2016): 80,000