Since the recession began, the economy has eliminated a net total of roughly 4.4 million jobs, with more than half of those positions  some 2.6 million  disappearing in the last four months alone. This rapid deterioration has prompted talk that some industries are being partly dismantled. Layoffs are multiplying because of dysfunction in the financial system, which is prompting even healthy companies to shed workers and shut down operations out of concern they may soon lose access to credit.

“Everybody is so fearful that companies are thinking, ‘What can we hang on to and what should we liquidate?’ ” said Martin N. Baily, a chairman of the Council of Economic Advisers under President Clinton and now a fellow at the Brookings Institution. “A lot of the reduction in employment is businesses deciding to close down operations or get out of a line of certain activity.”

American car sales have dropped to an annual pace of nine million, from some 17 million in 2007. Even if sales increase considerably, that is likely to leave a lot of unneeded auto factories.

“The decimation of employment in legacy American brands such as General Motors is a trend that’s likely to continue,” said Robert E. Hall, an economist at Stanford University’s Hoover Institution. “We have to stimulate the economy to create jobs in other areas.”

In February, 168,000 more manufacturing jobs were eliminated, bringing losses over the last year to 1.2 million. In Michigan, where the troubles of the auto industry have been particularly traumatic, the unemployment rate sits at 10.6 percent, the highest of any state in the nation.

“The people who do what I do in the Detroit area are a dime a dozen,” said Kim Allgeyer, 46, a machine toolmaker in Westland, Mich., who was laid off in January from a company that makes assembly lines for the automakers. Unable to find another full-time job, he is subsisting on day labor and one-week stints for contractors. “Who’s going to put me to work?” he asked. “Where’s the work at? It’s just a great big black hole.”

Much the same can be said for financial services, which gave up 44,000 jobs in February. During the housing boom, banks hired tens of thousands of well-compensated traders, analysts and marketers to sell mortgage-backed securities and other investments. That industry is unlikely to return to its former shape.