The Monster Worldwide Inc. employment index fell two points in September to a reading of 119 after having risen seven points in August.

"Despite recent improvements in economic sentiment, U.S. employers continue to exhibit caution when it comes to hiring," said Jesse Harriott, senior VP and chief knowledge officer at Monster. "On the upside, demand for workers is firming in the blue-collar segment, with welcome signs of revived activity in construction and manufacturing."

Monster's index is based on a review of online job ads taken from a selection of corporate career Web sites, including Monster.