Train Wreck is absolutely right.
At Microsoft, they don't even look at their divisions numbers. Nobody at the Microsoft Entertainment Division has any responsibilty, because they can just point to the company's numbers. In fact, that's why Microsoft is such a profitable company, nobody knows and cares how the money is earned, they all just look at the fiscal year's numbers and call it a day.
And yes, Xbox was a much more succesful product than even the PS2, GameCube and Gameboy Advance combined. Just take a look at Microsoft's revenue numbers from those years.