In the 19 nineties, if memory serves me correct, there were two big kind of detonations. One was orange county that i think lost two, two billion dollars unexpectedly. And i think it was proctuand gamble that lost hundreds of millions completely unexpectedly as well. By around 2 thousand and four all commodities are essentially deregulated for practical purposes. That means you can have an unlimited amount of speculative bets. It's a story told very well by watching the housing bubble or reading books like "The Great Depression," says Julian Zelizer.