More jobs being posted, but wages aren't budging

It's beginning to look like the job market is back. Getting a raise? Not so much.

After one of the weakest recoveries on record, the U.S economy has produced more than 200,000 jobs a month so far this year. Employers are posting more new positions at roughly the pace seen before the Great Recession unleashed a torrent of layoffs in 2007, according to the latest data released this week.

Some employers even complain that the labor market has gotten so tight they're having a hard time filing open positions. One simple explanation: those employers aren't boosting wages fast enough to lure candidates into taking those new jobs.

Truck driving is one of the jobs most in demand, but employers are having trouble finding drivers to hire.
Jetta Productions | Iconica | Getty Images
Truck driving is one of the jobs most in demand, but employers are having trouble finding drivers to hire.

"Businesses demand workers and the workers are supposed to magically appear," economist Joel Naroff said in a note this week to clients of Naroff Economic Advisors. ""But wages need to rise to attract the needed workers."

So far, that hasn't happened. While job openings overall are up nearly 20 percent in just the past year, wages have only risen by about 2 percent—roughly the rate of inflation. In real terms, wages have been flat. That may help explain why employers complain they can't fill some jobs.

But many hiring managers blame a shortage of skilled workers. When Express Employment Professionals, a staffing firm, recently surveyed its local franchises, some 83 percent said it was "somewhat difficult" or "very difficult" to fill job openings, up from 78 percent last year. More than half said they couldn't find enough qualified candidates.

Some jobs are harder to fill than others. Companies surveyed by Manpower Group, another staffing company, said the toughest occupations are skilled trades, sales reps, truck drivers, IT workers, accountants, engineers, managers and teachers.

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Despite these perceived shortages, employers have made little effort to lure qualified workers with higher wages. The leisure and hospitality industry, for example, had roughly 4.5 job openings for every 100 industry workers in May, according to the latest data from the Bureau of Labor Statistics. But wages are up just two-tenths of a percent in the last year; in real terms, they've fallen.

The same holds for workers in most industries, where wages haven't kept up with inflation—despite the pickup in demand from employers.

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"Except for those at the top, wages have consistently declined over the past few years," said Rebecca Smith, deputy director of the National Employment Law Project, an advocacy group for workers.

Workers aren't the only one eyeing wage gains warily. The Federal Reserve is keeping a close watch on the pace of job openings and hiring as a possible signal that inflation may begin to pick up.

"It is just a matter of time before the official wage-rate data show a clear uptrend," Jim O'Sullivan, chief economist at High Frequency Economics, said in a note to clients. "We also believe the recent strengthening in core inflation is more than just noise."

Higher inflation has recently shown up in consumer prices—especially at the grocery store, where a severe drought in key farm states like California has sent the cost of some meats and produce skyrocketing.

So far, the Fed hasn't indicated it's worried about inflation, which is still running at about 2 percent a year. As long as that continues, the Fed has some leeway in keeping interest rates low.

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But a pickup in wages could mark the early stage of a persistent inflation rise, especially if wages and consumer prices being to rise in unison. That would likely force the Fed to raise rates earlier—and faster—than expected.

And while the pickup in job openings is a convincing sign the U.S. economy is finally on the mend, it's far from clear whether it's ready for the dampening impact of higher borrowing costs.

By CNBC's John Schoen