Like Taibbi, Kaufman traces the beginnings of the increased commodity price volatility to 1991, presumably when the CFTC granted Goldman the exemption from the 5000 contract speculative limit in the commodities futures markets.

FORBES: Commodity Bubble Redux In Full Effect

In awarding a contract to run a public service, such as a railway, there is a balance to be struck between making the contract long enough to encourage serious investment and not so long that the forecasts built into bids for the contract become highly speculative.

BBC: What derailed the Transport Department

"Every financial system that we have ever seen in history has had a tendency to speculative over-investment, to overreach itself, and then to contract in the form of a crisis, " Mr Pettis says.

BBC: The year in business: 2012