If you want to know what financial innovation can do when conditions in the petri dish are just right, you would do well to take a look at the over-the-counter market in interest rate swaps. The first interest rate swap was struck between IBM and the World Bank in 1981 and within six years there were $865.6bn worth of such contracts flying around.

By June last year, when the Bank for International Settlements reported the most recent figures, the notional value of outstanding interest rate swaps had increased by 27.1% from the year before to hit $441.6 trillion.