More than half of those 80M were sold in the Americas which give you a clue what it was the market where GBA performed best.
In Japan GBA performed good but could have done better.
?.
2001: 4.2 million
2002: 3.8 million
2003: 3.8 million
2004: 2.4 million (DS release)
I don't see huge drop before DS release. It just had ridiculously short life thanks to Nintendo rushing DS against PSP.
Ah, okay thanks - that's less than I would've imagined. Thought it would be between 15 - 20m and a lot closer to 20.