4 ways the market could really surprise you

It's impossible to time a stock market crash, but the chances that something bad will happen should always be on investors' minds. Here are four wild, yet plausible, blowup scenarios.

Computers tank the stock market
trades automated chart 3

Most trades today are ordered up by computers, and at speeds measured in milliseconds. The good thing is that this lowers costs. But more automation raises the risk of "flash crashes," in which a mistaken trade starts a chain reaction of robo-selling.

"A program can do something dumb at a much faster rate than a human," says finance and information technology professor Terrence Hendershott of UC-Berkeley.

In 2005, the average time to execute a trade on the New York Stock Exchange was 10 seconds. By 2012, that time dropped to 8/10,000 of a second.


  @Money - Last updated January 28 2013 01:31 PM ET
Join the Conversation
Top stock picks from top pros

In the topsy-turvy market of the past five years, these managers led their funds to the best performances. Here's what they're bullish on now.

Market indexes are shown in real time, except for the DJIA, which is delayed by two minutes. All times are ET. Disclaimer LIBOR Warning: Neither BBA Enterprises Limited, nor the BBA LIBOR Contributor Banks, nor Reuters, can be held liable for any irregularity or inaccuracy of BBA LIBOR. Disclaimer. Morningstar: © 2014 Morningstar, Inc. All Rights Reserved. Disclaimer The Dow Jones IndexesSM are proprietary to and distributed by Dow Jones & Company, Inc. and have been licensed for use. All content of the Dow Jones IndexesSM © 2014 is proprietary to Dow Jones & Company, Inc. Chicago Mercantile Association. The market data is the property of Chicago Mercantile Exchange Inc. and its licensors. All rights reserved. FactSet Research Systems Inc. 2014. All rights reserved. Most stock quote data provided by BATS.