The number of Americans filing first-time claims for unemployment benefits rose last week to the highest level in almost four months, a sign the slowing economy is weakening the labor market.

Initial jobless claims increased by 34,000 to 406,000 in the week ended July 19, from a revised 372,000 the prior week, the Labor Department said Thursday in Washington. The filings exceeded economists' forecast and were the most since 406,000 in the week ended March 29.

U.S. employers are reducing workers as surging fuel costs, a three-year housing slump and a crisis in credit markets restrains demand. Rising joblessness reinforces concern that consumers will pull back on spending, which accounts for more than two-thirds of the economy.

"The job market is weakening, and the numbers this morning confirm that," Brian Bethune, an economist at Global Insight Inc. in Lexington, Massachusetts, said in a Bloomberg Television interview. "The economy is growing but at very slow rates."

Over a six-month period, payrolls have declined for a total loss of 438,000 workers and the payroll in April and May was revised to 52,000 more jobs.

The U.S. economy has lost jobs every month since the beginning of this year and it shed 62,000 jobs in June and up to 49,000 jobs in May. Last year, the economy created on average 91,000 new jobs each month.

Initial claims for state unemployment benefits rose 69,000 in the week ended Jan. 26, reaching 375,000, the Labor Department reported Thursday. It marked the highest level since early October -- and the biggest weekly jump since September 2005 in the wake of Hurricane Katrina.

Before this sharp rise, jobless claims had fallen by a net of 51,000 since late December, confounding economists who had expected claims to gradually rise as the nation's economy slowed.

Analysts had been expecting an increase, but nothing nearly as large as last week's gain: The consensus forecast as compiled by MarketWatch had called for claims to rise to about 320,000.

Most companies are just beginning to wake up to the popularity of IM in the workplace. While more than a third of employees use instant-messaging services at work, only 31% of organizations have policies in place that specifically restrict the use of IM, according to a survey on workplace monitoring by the American Management Association and the ePolicy Institute. But the issue has caught the attention of leading industries. The National Association of Securities Dealers requires member firms to "supervise" the use of instant messaging the same way they do written and electronic communications and to retain electronic copies of instant messages for at least three years.

The survey found that only 13% of companies have started logging IM records, but the crackdown is starting to take effect: About 2% of employers have fired employees for something they said over IM. By comparison, the study said, 26% of companies have terminated employees for misuse of email.

There are several ways users can save IM sessions. Google Inc.'s Google Talk instant-messaging service automatically saves the chat sessions of users that have signed in with Gmail email accounts. Users of Google Talk can disable the setting or choose to go "off the record" during a particular session if they want to avoid having it saved. Other instant-messaging services, such as AOL's AIM, Yahoo Inc.'s Yahoo Messenger, and Microsoft Corp.'s Windows Live Messenger, don't store conversations on their servers automatically. But they do offer various tools for companies and individuals to log conversations. Users can save an IM session by using a built-in save feature or by copying it into another file.