Interesting Facts

A company called Knight Capital started losing literally $10 million [£6.4m] a minute when they switched on a computer program for trading on the New York stock exchange. (They ended up losing $440 million [£281m], and their shares have now lost 71pc of their value since the error.  The result is the trading company is awaiting a rescue package from a rival firm.  Someone should make a film of the whole thing, and call it "When algorithms collide".)

Up to 70% of Wall Street trading is now run by so-called black box or algo-trading (algorithm trading). (In the so-called Flash Crash of 2:45 on May 6 2010, a five minute dip in the markets caused momentary chaos. A rogue trader was blamed for the 10% Dow Jones index fall but in reality, it was the computer program that the unnamed trader was using that was really to blame. The rogue algorithm sold 75,000 stocks with a value of £2.6bn in just 20 minutes, causing other super-fast trading algorithms to follow suit. The market recovered minutes later, and all the chaos forced regulators to introduce circuit breakers to halt trades if the machines start misbehaving, but what really worries me is that no-one has ever managed to figure out what happened.)