“Just when you need the theory to work it breaks down,” said a central banker at the height of the financial crisis. The words sum up the frustration felt by market participants at the failings of the efficient market hypothesis.

Speaking in November, HSBC chairman Stephen Green accused the efficient market hypothesis of helping fuel the bubble mentality by encouraging herd behaviour. Green said: "[It] told us there would always be a price for anything and that market arbitrage would ensure the price would always reflect value."