New claims for unemployment benefits jumped last week to a 16-year high, the Labor Department said Thursday, providing more evidence of a rapidly weakening job market expected to get even worse next year.

The government said new applications for jobless benefits rose to a seasonally adjusted 542,000 from a downwardly revised figure of 515,000 in the previous week. That was much higher than Wall Street economists’ expectations of 505,000, according to a survey by Thomson Reuters.

The department said that was also the highest level of claims since July 1992, when the economy was coming out of a recession.

The four-week average of claims, which smooths out fluctuations, was even worse: it rose to 506,500, the highest in more than 25 years.

In addition, the number of people continuing to claim unemployment insurance rose sharply for the third straight week to more than four million, the highest since December 1982, when the economy was in a painful recession.

Those figures partly reflect growth in the labor force, which has increased by about half since the early 1980s.

The figures will probably cause some economists to increase their projections for the unemployment rate this year. Many already expect unemployment to reach 7 percent by early next year and 8 percent by the end of 2009.

The rate in October was 6.5 percent, and last year the rate averaged 4.6 percent.

The Federal Reserve released projections on Wednesday that the jobless rate will climb to 7.1 percent to 7.6 percent next year, according to documents from the Fed’s Oct. 29 closed-door deliberations on interest rate policy.

Initial claims have been driven higher in the last several months by a slowing economy hit by the financial crisis, and cutbacks in consumer and business spending.

Economists consider jobless claims a timely, if volatile indication of how rapidly companies are laying off workers. Employees who quit or are fired for cause are not eligible for benefits.

In another economic report, a private research group says the economy’s health declined further in October as stocks, building permits and consumer expectations all fell.

The Conference Board says its monthly forecast of future economic activity declined 0.8 percent in October, worse than the 0.6 percent decrease expected by economists surveyed by Thomson Reuters.

The index, which weighs indicators like manufacturers’ new orders and supplier deliveries, has fallen four of the last six months. It rose slightly in September, thanks to federal interventions that increased the money supply.