Female workers represented by unions earn nearly $2.00 more per hour on average than those who are not union-represented, according to a report released Dec. 2 by the Center for Economic and Policy Research.

The report, Unions and Upward Mobility for Women Workers, is the latest in a series of reports issued by CEPR on the "union wage premium" for various groups of workers, including Latinos (182 DLR A-12, 9/19/08) and blacks (62 DLR A-6, 4/1/08).

CEPR is a Washington, D.C.-based research organization.

In CEPR's study, researcher John Schmitt analyzed data from the Census Bureau's monthly current population survey of 60,000 households. In addition to the wage premium discussed in the report, Schmitt also said female workers represented by unions are more likely to have health insurance and a pension plan.

Over the four-year period from 2004 through 2007, CEPR said, about 13.5 percent of all workers were represented by unions, while about 12.5 percent of female workers were union-represented. Unadjusted figures showed that the median hourly wage for union-represented women was $18.77 per hour, while nonunion female workers earned an average of $13.30 per hour.

At the same time, Schmitt said, 75.4 percent of union-represented female workers had health insurance, and 75.8 percent had a pension plan, compared with 50.9 percent of nonunion women with health insurance and 43.0 percent with a pension.

The report cautioned, however, that these figures "may overstate the union effect because union workers may be more likely to have characteristics associated with higher wages such as being older or having more formal education." For that reason, Schmitt said he used "standard regression techniques to control for these potential differences in the union and non-union workforces."

In this analysis, Schmitt found that union-represented women earned 11.2 percent more than their nonunion counterparts, or $1.94 per hour more. Although not included in the report, Schmitt told BNA that the median hourly wage for union-represented women, adjusted for differences, would be about $18.29 per hour, while a median regression-adjusted wage for nonunion female workers would be about $16.35 per hour.

At the same time, CEPR said in its regression-adjusted analysis, union-represented female workers were 18.8 percentage points more likely than their nonunion counterparts to have health insurance coverage, and 24.7 percentage points more likely to have a pension.

In addition, the report said that union-represented women working in low-wage occupations had wages that were 14.3 percent higher than their nonunion counterparts, and were 26 percentage points more likely to have health insurance. These low-wage female workers who were union-represented also were found to have a 23.4 percentage point greater likelihood of pension coverage, CEPR said.

"These benefits are large in economic terms, even when compared to extensive public and private investments in education," the report said. The report compared the effect of unionization on women's wages to the effect of a college degree. "For the average woman, a four-year college degree boosts wages 52.6 percent, relative to a woman with similar characteristics (age, race, state of residence) who has only a high school degree," it said. "The comparably estimated union wage premium is 11.2 percent--over 20 percent of the full four-year college effect."

In a statement, the Service Employees International Union pointed to CEPR's study as "evidence of why it's so important for working women, and others, to have the freedom to join unions."

CEPR concluded that the report's findings "strongly suggest that better protection of workers' right to unionize would have a substantial positive impact on the pay and benefits of women in the workforce."