Nearly everyone in the U.S. that wants a job has one. But how good are they?

U.S. unemployment is at its lowest ever. Nearly everyone that wants a job can find one. The demand for workers in America is nearly unprecedented.

But what is the quality of these jobs? A team of researchers set out to answer that question. Here’s what they found …

They recently unveiled the US Private Sector Job Quality Index (or JQI for short), a new monthly indicator that aims to track the quality of jobs instead of just the quantity. The JQI measures the ratio of what the researchers call “high-quality” versus “low-quality” jobs, based on whether the work offer more or less than the average income.

And what does that mean for American workers?

“The problem is that quality of the stock of jobs on offer has been deteriorating for the last 30 years,” says Dan Alpert, an investment banker and Cornell Law School professor who helped create the index. (Along with Alpert, the index is built and maintained by researchers at Cornell University Law School, the Coalition for a Prosperous America, the University of Missouri-Kansas City, and the Global Institute for Sustainable Prosperity.) The “whole story” told by the index, he adds, is “the devaluation of American labor.”

The Great American Labor Paradox

No one wants to hear that. But the numbers bear it out.

Since 1990, America has cumulatively added some 20 million low-quality jobs, versus around 12 million high-quality ones. In short, the US economy has shifted toward creating more bad jobs than good.

And the numbers point to a real cause for the devaluation of American labor – the loss of US manufacturing jobs.

Throughout the second half of the 20th century, US manufacturing supported around 12.8 million production jobs. Then, all of a sudden, America started hemorrhaging factory jobs. By 2010, the number had shrunk to levels last seen in 1939, when the US population was two-fifths of its current size. Although it’s recovered a bit since, manufacturing jobs are still down more than a quarter since 2000.

Nearly all of the manufacturing jobs lost, say the JQI researchers, have been replaced by just four service-sector industries: retail, administration and waste services, healthcare, and leisure and hospitality. In all of these industries, jobs with lower-than-average income predominate.

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