Deepening economic doubts cut away at market gains

The market headed down from the start this morning as Securities and Exchange Commission (SEC) Chairman Mary Schapiro and Commodity Futures Trading Commission (CFTC) Chairman Gary Gensler discussed the unusual market events of May 6 before a subpanel of the Senate Banking, Housing and Urban Affairs Committee. 

The SEC and CFTC have formed a joint advisory panel to examine the market plunge two weeks ago but haven't determined its cause. The federal regulators have suggested several changes including a circuit breaker that would halt trading on individual stocks under certain circumstances and possible recalibrations of current market controls.