NEW YORK (CNN/Money) - The number of Americans filing new claims for unemployment benefits rose slightly last week, a government report said Thursday

Initial claims for jobless benefits rose by 1,000 claims to 323,000 in the week ended May 21 from an upwardly revised 322,000 for the previous week, the Labor Department said.

Economists surveyed by Briefing.com had expected claims to climb to 325,000 from the 321,000 originally reported in the week ended May 14.

Weekly claims came in weaker than forecast, but the Labor Department said there were no special factors contributing to the sluggish increase.

The closely watched four-week moving average, which evens out fluctuations in the more volatile weekly reports and provides a clearer picture of job-market trends, rose to 330,500 from an upwardly revised 330,000 in the previous week.

Moreover, the number of people remaining on benefit rolls after drawing a week of aid fell to 2.57 million in the week ended May 14, the latest week for which data are available.

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