When wages for people with bachelor's degrees declined in the 1970s, the cause was a flood of baby boomers entering the job market.
This time, economists say, much of the blame goes to trends familiar to workers with less education, who are now creeping up the wage ladder.
Offshoring, which has shifted manufacturing and call-center jobs to such nations as Mexico and India, is increasingly affecting white-collar sectors such as engineering and software design.
And companies have continued their long effort to replace salaried positions with lower-paid, nonsalaried jobs, including part-time and freelance positions without benefits. Those contingent positions make up nearly half of the 6.5 million jobs created since 2001, said Paul Harrington, a labor economist at Northeastern University in Boston.
Harrington said the number of salaried jobs increased an average of 11.5% during the last five economic recoveries, compared with 2.5% during the current recovery.
"There's clear deterioration in the college labor market," he said. "The American economy just does not generate jobs the way it has historically."
Employment recruiter Alan Guarino has seen a similar change in his work. He says about 15% of workers with four-year college degrees are working at "gray-collar" jobs below their skill level, such as in retail, mainly because they cannot find better-paying jobs; before 2001, the figure was about 10%.
"A very significant percentage of the jobs we are creating are contingent jobs," not salaried positions, said Guarino, chief executive of Cornell International, a staffing firm.
Jonathan Hess, 25, took a low-paying job -- and then found himself falling further behind.
A graduate of UC Santa Cruz, Hess has been working as a clerk at a Borders bookstore in San Francisco. Until recently, he was earning $1,300 a month, living paycheck to paycheck. Then the manager reduced staffers' hours and forced them to use their vacation time to avoid unpaid leave.
"It's a good corporation, but the wages are barely livable," Hess said of Borders Inc. "Anybody who's using it as their sole means of surviving -- it's tough."
J. Tony Smith, 38, won a $5,000-a-year raise at his Web design job with a San Francisco art school, which boosted his salary to $55,000. But that has been his only raise in almost three years.
Smith feels like he has stalled while inflation hasn't.
