Exchanges Agree on New ‘Circuit-Breakers’

U.S. stock markets agreed on a plan to widen the “circuit breakers” that halt trading during a market plunge. The agreement calls for markets to close for an hour if the Dow Jones industrial average falls 10% before 1 p.m. Eastern time, a half-hour if that decline occurs between 1 and 2:30 p.m., and for the rest of the day if the index falls 10% after 2:30 p.m. Also, any decline of 20% overall would trigger a trading suspension for the rest of the day. Currently, a Dow loss of about 5% triggers a temporary halt. The 11 U.S. stock, options and commodity markets will ask their boards to approve the plan. The Securities and Exchange Commission then will make the final decision.