New research shows that the much-discussed measure of requiring firms to disclose gender segregated wage-statistics to clarify differences in women´s and men´s wages reduces the pay gap by 7 percent. An important step in the right direction and knowledge that can boost the ambition to ensure women the same pay for same work, researchers say.

NEW YORK – Women are paid less for the same work as men in the labor markets of most developed countries. When a man earns 100 dollars, a woman earns 78.5 dollars in Germany, 79 dollars in the UK and 83.8 on average across EU-countries according to 2016-statistics from Eurostat.

Reducing the gender pay gap has been at the epicenter of a heated debate among academics, policy makers and unions for years, and legislation that require employers to publish gender-based wage-statistics to provide pay transparency has been proposed nationally and internationally in the belief, that this would promote equal pay.

Opponents of pay transparency have argued that disclosing gender differentiated pay statistics increases the administrative burden of firms, violates employee-privacy and confidentiality - and that the effect of all this hassle is unclear or even non-existing.

But new research from Columbia Business School, INSEAD, the University of Copenhagen, University of North Carolina Kenan-Flagler Business School and Cornell SC Johnson College of Business shows that pay transparency has a positive impact on closing the wage gap. Columbia Business School Professor of Finance and Economics Daniel Wolfenzon and his co-authors, released a working paper examining the effect of a 2006 requirement for Danish companies to report on gender pay gaps by proving gender specific wage statistics, find that the legislative step could be a promising new avenue for closing the gap.

Effect of 2006 Legislation Analyzed

The researchers examined wage statistics of companies prior to, and following, the introduction of Denmark’s 2006 Act on Gender Specific Pay Statistics’ which obligates companies with more than 35 employees to report on gender pay gaps. In order to fully comply with the new transparency law, firms additionally needed to have at least ten men and ten women within a given occupation.

They analyzed data from 2003 to 2008 and focused on companies with 35-50 employees and compared their pay data with identical information from a control group of firms with 25-34 employees – firms of a similar size but that were not required to release gender-segregated data.

The firms in the analyses paid their male employees an 18.9% wage premium before the regulation was introduced, which is statistically significant for both firms that complied with the legislation and those who did not. The researchers ensured that this difference in men’s and women’s pay was not driven by differences in demographics, work experience, macro trends or selection into specific occupations.

After the regulation the researchers found that the gender pay gap had shrunk  to 17.6 percent in the approximately 1000 Danish firms governed by the new 2006-legislation relative to the control firms, that were not required to publish pay statistics – a reduction of 7 percent.

“For the first time we are able to document, that pay-transparency really works. A 7 percent reduction in the pay-gap may not sound impressive, but given the fact that only a limited number of firms in Denmark are governed by this legislation the effect is significant. We can even prove the effect amongst firms that were not required to provide gender segregated pay-statistics. We know now that wage-transparency works and it is a measure that can be applied nationally as well as internationally. So from this point, it is really just a question of whether or not the politicians actually wish to do something about the pay-gap between men and women,” says Professor of Economics Morten Bennedsen, from INSEAD and the University of Copenhagen.

Overall Wage Costs Grew Slower

Although wages for both male and female employees increased during the period analyzed, the researchers found an overall decline in the wage premium for male employees in firms subject to the legislation, explains Professor Wolfenzon, the Stefan H. Robock Professor of Finance and Economics and Chair of the Finance Division at Columbia Business School.

“What surprised us the most was the way in which this wage gap closed. Women’s wages did not increase at a faster rate in treatment firms as we were expecting. Instead, we find that men’s wages in treatment firms grew slower relative to men’s wages in control firms. As a result, the total wage bill grew slower in firms that were required to report wage segregated statistics,” Wolfenzon said.

Experimental literature has shown that men on average are better at negotiating wages than most women, and that they are comfortable asking for high salaries and bonuses.

“But disclosure of wage statistics makes the gap between men´s and women´s pay very transparent to the outside world, and it seems that this makes firm managers able to halt exorbitant pay claims from male employees,” says Morten Bennedsen.

More Women Hired and More Women Promoted

The researchers additionally found, that the reduction in the pay gap between men and women varied greatly between different types of firms. The reduction in the wage gap was bigger in firms where company executives themselves have more diverse families – especially if they have more daughters than sons. This was also the case in industries that had larger wage gaps prior to the legislation.

The 2006-pay transparency legislation also seems to have a couple unintended gender-related consequences: Firstly, firms included in the legislation hired 4% more women in the intermediate and lower hierarchy levels than control firms, suggesting firms are able to attract more female employees in positions where they offer higher wages.  Other spillover effects appear to be, that more women were promoted from the bottom of the hierarchy to more senior positions, after the implementation of the law, while researchers found no significant change in promotions for male employees.

“What is interesting is that the law has unintended consequences on women’s ability to climb up the corporate ladder and their willingness to join the labor market. When firms adopt fairer wage practices towards women, this can have positive effects on women’s labor market outcomes that go well beyond pay gaps,” says Assistant Professor of Finance Elena Simintzi at the University of North Carolina Kenan-Flagler Business School.

A few negative consequences of the legislation found by the researchers include a 2.5 percent decline in productivity in the affected firms. But with the simultaneous 2.8 percent reduction in the firms’ total wage costs, there was no significant effects on overall firm profitability.

“We can´t tell for sure, why we see this decline in firm productivity. It could be that information on gender pay gaps simply lowers job satisfaction for female employees who find out, that they are paid below their reference group, or because male employees are dissatisfied with not getting the wage increases, they ask for,” says Margarita Tsoutsoura, Associate Professor of Finance, Cornell SC Johnson College of Business.

To read the study, click here: Do Firms Respond to Gender Pay Gap Disclosure?

To learn more about the cutting-edge research taking place at Columbia Business School, please visit www.gsb.columbia.edu.

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