- US Markets Bracing for Selloff on Dubai Debt Worries
- Dubai Struggles to Ease Debt Fears; Investors Rattled
- US Dollar Falls to 14-Year Low Against the Yen
- UK's Darling to Downgrade 2009 Growth Forecast
- US Companies Already Moving on Curbing Emissions
- Fannie Mae to Tighten Lending Standards: Report
- Investing in Good Karma – and Making a Profit
- Retailers Should Believe in Christmas Miracles
- Bankruptcies Jump, Hitting Highest Level in Four Years
- 4 Thanksgiving Week Buys For Your Portfolio: Market Pros
- There's a 'Great Chance' For a Double-Dip Recession: Strategist
- Revenge of the Gangsta Nerds
- Will TCU See The "Flutie Effect?"
- Retail Earnings and Sales to Improve in Q4: Analyst
- Consumers Catching the Holiday Spirit
- It's Beginning To Look A Lot More Riskless
- Crescenzi: Claims Level Suggests End to Job Losses
- Hedge Funds Take Early Lead in Warren Buffett's 'Big Bet'
MOST SHARED
- Kuoni CEO Sees Recovery in Travel Sector
- Dubai Struggles to Ease Debt Fears; Investors Rattled
- Gold Retreats from Record High as Dollar Rebounds
- China Unveils Carbon Target Ahead of Copenhagen
- Great Britain, No Longer That Great: Investor
- Euro Shares Record Biggest Drop in 7 Months
- Fannie Mae to Tighten Lending Standards: Report
- US Markets Bracing for Selloff On Worries About Dubai's Debt
- UK's Darling to Downgrade 2009 Growth Forecast
- No Thanksgiving Rest for Retailers in Sales Race
Text Size 
As harrowing as the U.S. stock market's plunges have been in recent weeks, they've yet to be been enough to trigger the "circuit breaker", or trading halt, mechanisms that result in an automatic timeout in trading.
The Big Board implemented the automatic halts after the stock market crashed in October 1987 to force traders to take a break from frenzied selling.
The Dow Jones industrial average would have to fall 1,100 points in a day to trigger the first halt.
If that decline is reached before 2 p.m., the market will shut down for an hour. If the threshold is breached between 2 p.m. and 2:30 p.m., the halt will last 30 minutes. No trading stops would take place if the plunge occurs after 2:30 p.m.
If the index were to fall 2,200 points before 1 p.m., the market would close for two hours. If such a decline took place between 1 p.m. and 2 p.m., there would be a one-hour pause. The market would close for the day if stocks sank to that level after 2 p.m.
In the event of a 3,350-point decline, the market would close for the day, regardless of the time.
The thresholds are computed at the beginning of each quarter to establish a specific point value for the quarter. The 1,100-point drop represented a 10 percent decline at that time; the 2,200 level, a 20 percent drop and the 3,350 level is a 30 percent drop.
The rules would halt trading on the major securities and futures exchanges in a coordinated cross-market halt if the circuit breaker is enacted.
The last time the markets were shut down was during the 9/11 period.
Print
Email
- What you need to know.
- Ever wished your cab driver would stop nattering and just get to where you're going? Well that moment is near(er).
- Eric Schmidt pledges to create a virtual copy of the Iraq National Museum at Google’s expense.
- Bill Griffeth is taking a leave of absence from CNBC and Power Lunch for a year. Here's a message from Bill.
- More shoppers than ever plan to comparison-shop this season. Who will benefit?
- It may be the most unusual guide to business you'll read.
Data is a real-time snapshot *Data is delayed at least 15 minutes