The 2010 'flash crash': how it unfolded

In just 20 minutes the New York Stock Exchange had witnessed it's biggest stock plunge in decades, all traced to one gargantuan sell order

It was 6 May 2010. In the UK it was general election day, in the US,Wall Street was gripped by mounting anxiety about the Greek debt crisis. The euro was falling against the dollar and the yen, but despite the turbulent start to the trading day, no one had expected the near 1,000-point dive in share prices.

In a matter of minutes the Dow Jones index lost almost 9% of its value - in a sequences of events that quickly became known as "flash crash" . Hundreds of billions of dollars were wiped off the share prices of household name companies like Proctor & Gamble and General Electric. But the carnage , which took place at a speed never before witnessed, did not last long. The market rapidly regained its composure and eventually closed 3% lower.

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