Ladies, don't celebrate that promotion or raise just yet. Working women in the United States still face a bigger wage gap than those in other countries.

Of 38 countries assessed in the International Labour Organization's Global Wage Report 2014/15, released Friday, Americans had the widest reported total gap, at 36 percent. That's a bigger paycheck bite than the Census Bureau's most recent estimate, which has women earning 78 cents for every dollar men earned. In comparison, the ILO report's front-runner, Sweden, has a pay gap of just 4 percent. (See chart below for a comparison of the gaps in developed countries.)

Census Bureau figures focus on men and women working full-time. "In other countries, the part-time workers, the hourly wages are more equal than they are here," said Jeff Hayes, a study director for the Institute for Women's Policy Research. That could account for some of the ILO's wider gap.

Researchers adjusted some of the wage gap to account for differences in education and other "explainable" qualification disparities. The "unexplained" portion remaining, they wrote, can suggest discrimination. According to the report, "If this 'unexplained' wage penalty were erased, the gap would actually be reversed in nearly half of the 38 countries, and women would earn more than men based on work-related characteristics." (The U.S. would still rank at the bottom, however.)

SOCIAL

Two Numbers: The Gender #PayGap - what does it really mean and how can we explain it: http://t.co/mGPBzCJp3A — TheWomen'sFoundation (@TheWomensFndtn) December 5, 2014

Gender pay gap widens for higher-earning women http://t.co/LAgK1lrJe9 — ILO (@ilo) December 5, 2014

-- Kelli B. Grant, CNBC