U.S. stocks fell for the week, sending the benchmark indexes to their worst retreat since April, after Federal Reserve chief Ben S. Bernanke said he may phase out monetary stimulus. The S&P 500 slipped 2.1 percent to 1592.43 over the five days, trimming its 2013 gain to 12 percent. The Dow Jones industrial average sank 270.78 points, or 1.8 percent, to 14,799.40.

“There’s no clarity about what the Fed is going to do, and if you ask 10 people what will happen, you get 11 answers,” said Donald Selkin, who helps manage about
$3 billion of assets at National Securities.

Global equities slumped, with the S&P 500 posting the biggest two-day decline since November 2011, after Bernanke said that the Fed may begin dialing back its unprecedented bond-buying this year and end it in mid-2014 if the economy achieves the Fed’s objectives.

The S&P 500 has fallen 4.6 percent since May 21, the day before Bernanke suggested the Fed could start to taper if the economy improved in a “real and sustainable way.” Three rounds of monetary stimulus and corporate earnings that beat forecasts have propelled the bull market in U.S. stocks into a fifth year. The benchmark index has risen 135 percent from a 12-year low in 2009.

The Treasury will sell $30 billion in three-month bills and $25 billion in six-month bills Monday. They yielded 0.055 percent and 0.09 percent in when-issued trading. The Treasury will also sell
$25 billion of 52-week bills and $35 billion of two-year notes the following day, as well as $35 billion of five-year notes Wednesday and $29 billion of seven- year notes Thursday.

— Bloomberg News