I don't think he took credit for it as much as everyone just sort of gave it to him... Always the way it goes.
And it's all placed on too immediate a responsibility, too. Bush took all the blame for the economic crash, even though it was to a great extent caused by the bad loans that powered the unsustainable economic boom that helped Clinton balance the budget. And Obama was soundly criticized for how slowly we came out of it. And realistically none of them were all that culpable, though each of the 3 certainly played at least a small role...