New Unemployment Claims Increase by 4,000: The number of Americans filing first-time claims for unemployment insurance totaled a seasonally adjusted 336,000, the Labor Department said. It was the first increase in three weeks. The figures fueled debate among economists over whether the job market is weakening. "The initial unemployment claims data continue to indicate a slowdown in the labor market," said Marilyn Schaja, an economist with Donaldson, Lufkin & Jenrette Securities Corp. in New York. Not so, said economist Samuel D. Kahan of Fuji Securities Inc. in Chicago. Claims tend to jump in February because of difficulties in making seasonal adjustments to the data, he said.