Is Obamacare causing a surge in part-time work?

In the political close-combat before the Affordable Care Act took effect in January, a major criticism of the health insurance program was that it would spur employers to cut workers' hours, and perhaps even act as a "job-killer." The concern was that companies would shift people out of full-time jobs into part-time positions to avoid a financial penalty for failing to offer coverage to any employee who works at least 30 hours a week.

Such fears appear to have been unwarranted.

Data out this week from the U.S. Census Bureau shows that the percentage of Americans in full-time jobs rose last year, while the share of part-time workers fell. Nearly 73 percent of working-age men and 61 percent of women worked in full-time, year-round jobs in 2013, higher than the estimated 71 percent and 59 percent who did so the previous year.

If companies had been cutting workers' hours or hiring more part-timers, experts note, the share of people in part-time jobs should have increased over the last year. It hasn't.

"There's little evidence to date that health reform has caused a shift to part-time work," writes Paul Van de Water, a health care expert with the liberal-leaning Center on Budget and Policy Priorities, in an analysis of the latest Census numbers.

The share of U.S. employees in part-time jobs who would rather work full-time didn't decline only last year -- it has been falling throughout the recovery that followed the Great Recession. In 2009, the year the recovery officially began, 6.3 percent of workers reported being in involuntary part-time employment. By this year, that figure has fallen to just over 5 percent, economists Dean Baker and Helene Jorgensen of the Center for Economic and Policy Research note in a recent study.

What Obamacare does seem to have done, by contrast, is liberate more people to work part-time if they choose. Through the first six months of the year, 13.2 percent of U.S. workers were in voluntary part-time jobs, compared with 13.1 percent in 2013. Who is opting for part-time jobs? Mostly younger parents with children, according to CEPR, which supported Obamcare ahead of its passage in 2010.

"This is consistent with a story where many workers who previously needed to work full-time to get health care insurance at their job are taking the option of buying insurance on the exchanges and working part-time jobs in order to have more time to be with young children," Baker and Jorgensen write.

Obamacare's limited impact on the labor market is borne out by other research. Although the main headline out of a February study by the Congressional Budget Office was that the program would stifle job-creation, the agency found that "there is no compelling evidence that part-time work has increased as a result of the ACA."

Indeed, CBO did not try to measure whether employers were less likely to hire because of the new health law, as was widely reported at the time. Rather, it focused on whether people would stop working or shift to part-time employment now that they could get health coverage without holding down a job. And that appears to be the best option for at least some Americans, the latest federal data suggest.

It is early days for Obamacare, and it remains to be seen what impact it will have on the labor market over the long-term. The White House in February postponed the so-called employer mandate -- the portion of the ACA that requires companies with 50 to 99 full-time workers to offer health insurance or pay a $2,000 penalty -- until 2016 (Businesses with at least 100 employees must comply by January of next year.) Small businesses, which account for most new jobs, could reduce their hiring as the mandate gets set to take effect.

But for now, it is clear, most employers aren't responding to the program by shifting their workforce to part-time employees.