WASHINGTON (Reuters) - The number of U.S. workers signing up for jobless benefits fell by a bigger-than-expected 19,000 last week, and non-farm worker productivity was higher in the second quarter than first reported, government reports showed on Thursday.

Initial claims for state unemployment dropped to a seasonally adjusted 318,000 for the week ended September 1, from an upwardly revised 337,000 the prior week, the Labor Department said.

Analysts polled by Reuters were expecting claims to slip to 330,000 from the previously reported 334,000. A Labor Department official said there were no special factors behind the large decrease in jobless claims.

The dollar and stock futures rose on the data, while Treasuries prices slipped. U.S. interest rate futures trimmed implied chances of a half-percentage point interest rate cut by the Federal Reserve at its September 18 meeting.

Analysts said the numbers showed a stable labor market even as economic growth appears to have slowed.

"Companies appear to have been reluctant to cut staff, probably because the initial slowdown in growth was not followed by a further softening or recession. Demand has been weak enough to slow the pace of hiring but not to raise the pace of firing," said Ian Shepherdson of High Frequency Economics in Valhalla, New York.

The number of unemployed people still on the benefit rolls after drawing an initial week of aid was the highest since February. These continued claims rose by 25,000 to 2.598 million in the week ending August 25, the latest period these figures were available.

Analysts were expecting continued claims to inch up to 2.58 million from a previously reported 2.579 million.

STRONGER PRODUCTIVITY

A separate report showed that U.S. non-farm worker productivity grew at a slightly faster-than-expected 2.6 percent annualized pace in the second quarter, the highest since the third quarter of 2005, and labor costs rose a more moderate 1.4 percent.

Analysts were expecting productivity for the quarter to be revised up to 2.4 percent from the previously reported 1.8 percent. Unit labor costs were expected to be revised down to a 1.6 percent rise from the Labor Department's initial estimate of a 2.1 percent increase.

Unit labor costs, a gauge of inflation and profit pressures under close scrutiny from the Federal Reserve as it meets to decide on interest rates, were nevertheless up by 4.9 percent over the second quarter of 2006, the sharpest four-quarter increase since the third quarter of 2000.

Hourly compensation rose 4.1 percent in the second quarter, but when a 6 percent jump in consumer prices was taken into account, real hourly compensation fell 1.8 percent, the government said.