Associated Press Twitter account Hacked
The chart below is a two minute chart of the SPY on 04-23-2013. The Associated Press’s Twitter account got hacked and someone tweeted that the White House had been bombed. The Dow Jones Industrial Average dropped 145 points and recovered in about 7 minutes. The SPY is shown below, on a two minute chart the down move was over 30 standard deviations as shown on the red bar. This was an excellent example of the kind of market volatility that one tweet can produce, even though it turned out to be false.