Global stocks fell for a second day amid concern the economic recovery is faltering, with Standard & Poor’s 500 index adding to losses from its worst drop since August.

The MSCI All-Country World index lost 1 percent this morning. The S&P 500 slipped 0.5 percent after yesterday’s 2.3 percent tumble.

The S&P 500 remained at a six-week low as retailers fell after reporting disappointing sales and economists cut forecasts for U.S. payroll gains in May, adding to evidence the global economy is slowing. Limited Brands Inc., Gap Inc. and J.C. Penney Co. Inc. lost at least 1.8 percent to pace declines in 29 of 31 companies in the S&P 500 retailing index.

The S&P 500 has tumbled 4 percent from an almost three-year high at the end of April as data on manufacturing and housing trailed economists estimates and investors prepared for the Federal Reserve to complete its $600 billion bond-purchase program at the end of June.

“The market is vulnerable,” said Alan Gayle, senior investment strategist at RidgeWorth Capital Management in an interview with Bloomberg. “The latest data suggests that the recovery is losing momentum.”