When did Christina Aguilera debut with the album "Christina Aguilera"?

Explanation

Christina Aguilera (b. 1980) is an American pop artist and actress. She began her musical career as a child, when she sang the title song for the Disney movie "Mulan." Later, she released the albums "Christina Aguilera" (1999), "Stripped" (2002), "Back to Basics" (2006) and "Bionic" (2010). Christina Aguilera debuted as an actress with the movie "Burlesque" (2010).