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Tweet From Hacked AP Account Causes High Freq. Traders To Drop DOW 150 Points
New submitter Mike Lape writes "Stocks plunged and recovered within minutes after the hacked AP Twitter account sent out a tweet that indicated that the White House had been the victim of an explosion and that President Obama had been injured. '...the Dow Jones Industrial Average took a quick 143-point plunge, before recovering most of its losses within minutes. The three-minute plunge triggered by the tweet briefly wiped out $136.5 billion of the S&P 500 index's value, according to Reuters data. Interestingly, Tuesday has been the best day of the week for the blue-chip this year with an average return of 0.46 percent. If the index closes in the black today, it will have been up for the 15th consecutive Tuesday. The last time the Dow rose for 15 straight Tuesdays was in 1927.' An analyst said, 'That goes to show you how algorithms read headlines and create these automatic orders – you don't even have time to react as a human being.'"
I will point out something to buy and hold investors
The Bid / Ask spread has dropped by 90% in the past 30 years. You used to pay .5% to 2% for each trade – not it basically nothing. Moving to decimalization helped, but it is the HFT that really collapsed the spread. This is even truer for ETFs then for normal stock.
The fees that mutual funds and ETFs (which a lot of buy and hold investors hold) have also collapsed the past 30 years. Specifically for index funds, they have fallen by 90%. There are a lot of reasons for this, but about a quarter to a third is lower trading costs, which can be traced backed to HFT.
So, you save about 1% to get into a investment, and about .25% each year if that investment is a mutual fund.