Self-Regulation

The investment community also regulates itself, developing and enforcing ethical standards to reduce the potential for abuses in the financial marketplace. The Financial Industry Regulatory Authority (FINRA) oversees the nation's more than 3,700 brokerage firms and more 600,000 registered brokers. It develops rules and regulations, provides a dispute resolution forum, and conducts regulatory reviews of member activities for the protection and benefit of investors.

In response to "Black Monday" - October 19, 1987, when the Dow Jones Industrial Average plunged 508 points and the trading activity severely overloaded the exchange's computers - the securities markets instituted corrective measures to prevent a repeat of the crisis. Now, under certain conditions, circuit breakers stop trading for a 15-minute cooling-off period to limit the amount the market can drop in one day. Under revised rules approved in 2012 by the SEC, market-wide circuit breakers kick in when the S&P 500 Index drops 7 percent (level 1), 13 percent (level 2), and 20 percent (level 3) from the prior day's closing numbers.