The latest installment of Tim Harford's BBC/Open University podcast (RSS) More of Less has a fantastic and chilling look at the world of high-frequency automated stock trading, where warring algorithms execute millions of trades in an eyeblink. The story's jumping-off point is Knight Capital, whose faulty algorithm hemorrhaged $10,000,000 per minute, ultimately costing the company nearly half a billion dollars. But from there, Harford and co do a great series of examples trying to convey the sheer velocity of these markets. I've been following this stuff reasonably closely and had an abstract sense of it all, but this brought it home for me so firmly that it raised goosebumps.
Last week Knight Capital lost a lot of money very quickly. It was the latest chapter in the story of something called 'high frequency trading'. Investors have always valued being the first with the news. But high frequency trading is different: algorithms execute automatic trades, conducted by computers, at astonishing speeds. We ask: is the rapid growth of high frequency trading progress, or – as some think – a threat to the stability of the entire financial system?