Barely two weeks after President Bush signed a law granting an extra three months of benefits to jobless workers, the evidence is mounting that the U.S. job market truly has hit the skids. As a technical matter, the nation’s economy continues to expand — barely — but this one critical component is plainly headed into recession territory.

For newspaper headline writers, the official jobless rate and the count of monthly job gains and losses is often all that matters. At 5.5 percent for each of the past two months, unemployment may be uncomfortably high, but it’s not yet clearly in a trouble zone. The jobless rate was almost twice as large in the depths of the 1981-82 recession, and it didn’t fall much below its current level before another recession hit in 1990-91, sending it soaring again to almost 8 percent. Even in the wake of the relatively mild 2001 recession, unemployment rose to 6.3 percent, well above where it is now.

As for the payroll count, the economy has lost a bit more than 400,000 positions over the past six months (almost 600,000 over seven months when government hiring is ignored). But during the last recession, employers were shedding jobs at the pace of 200,000 a month. So, we’re not deep in the hole yet by that measure, either.

But when you look behind the headlines, the picture is far grimmer. A host of negative employment indicators are at their worst points since early 2004. That was a time when the last recession had run its course, the labor market actually was improving for workers and the jobless rate was falling. More striking, some more obscure gauges of the state of the workforce are getting close to the levels they reached at the worst point of the economy’s last downturn.

Measurements of labor underutilization, as the Labor Department refers to it, and of the duration of unemployment, show that an increasing number of people who want to work may be dropping out rather than trying to land jobs, and those who are out of work are staying on the unemployment lines longer.

One set of not-closely-watched government figures on monthly hires and separations paints a telling image of a workforce that’s getting worried and employers who have put their expansion plans on hold. Typically, the U.S. labor market is in a constant state of churning: Millions of workers quit their jobs or are let go every month, and many if not most of them are quickly rehired.

But the statistics for May show that for the first time since mid-2004, the number of “separations,” both voluntary and involuntary, exceeded the number of new hires. On top of that, the number of job quitters is declining — not surprisingly — while the number of involuntary separations (aka firings, layoffs and RIFs) is edging up.

The Labor Department has been reporting the hires and separations figures for only about eight years, and it doesn’t have a well-established track record. But what’s potentially troubling about the rising number of involuntary separations is that employers typically are reluctant to get rid of employees until they know the economy is headed down. And the data might indicate that companies are starting to throw in the towel.

Concern that things are likely to get much worse before they get better is why a growing number of economists and commentators have started to focus on ways to more precisely gauge the state of non-workers. In particular, labor market observers are closely monitoring a set of statistics that aggregate three groups of Americans who aren’t fully employed: those who say they are jobless but actively looking for work; those who say they would happily take a job but for a variety of reasons aren’t currently looking; and those who say they are working part time because there are no full-time positions available to them, because the economy is too weak.

This measure shows that almost 10 percent of the working-age population in June was either completely unable to find a job, too discouraged to look or unable to be fully employed — almost twice the official jobless rate. At the worst point after the 2001 recession, this figure reached only 10.4 percent, although it was much higher in the early 1990s, when official unemployment was also higher.

It’s also worth noting that in April 2000, about a year prior to the start of the last recession, the jobless rate had fallen to a 30-year low of 3.8 percent, and a record 64.7 percent of the U.S. population was employed. Neither labor market indicator came close to returning to those happy levels in the past eight years. So, one fear is that the potential exists for joblessness — by whatever measure — to rise much higher than in the recent past because the population hasn’t even come close to being fully employed during this decade.

Any country’s economy — the United States is no exception — is dependent upon its labor to grow. Workers do the producing, and workers earn the money that drives consumption — which accounts for about 70 percent of U.S. gross domestic product. A declining number of workers, almost by necessity, leads to declining consumption and slower economic growth. At this point, the outlook is that we’ll have many fewer workers for quite some time.

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