I think people get a bit off-track fetishizing banker pay, however. Even if the study had found that bankers roughly broke even between 2000 and 2009, it wouldn't be evidence that the trades were irrational. After all, most of the traders who went bust in the crash still have their jobs now that Wall Street is bouncing back. Their expected lifetime earnings aren't very different. But if any of these guys had held back between 2003 and 2007, if their quarterly returns had been low year after year and they brushed off their angry bosses by arguing that this seemed sort of like a bubble, they would have been fired. Looking at the immediate financial incentives of bankers is a lot weaker than looking at the career incentives of bankers.