Women who work in engineering or optics earn less than men, and the wage gap peaks mid-career, a new survey finds.
Median salaries for men in these fields were 36 percent higher overall than for women. The median salary for men was $79,755, compared with $58,431 for women. Men and women had the largest salary difference in Middle Eastern countries.
The findings were detailed in the International Society for Optics and Photonics (SPIE) 2013 global salary report.
Men earned 140 percent more than women in technical fields in the Middle East (at all income levels), 63 percent more in Asia (in higher-income jobs), 41 percent more in Europe (in higher-income jobs) and 32 percent more in North America (at all income levels), the survey found. The smallest gap was in Oceania, where men earned only 9 percent more than women in tech fields (at all income levels).
The engineering income gap between men and women was the widest during the mid-career years. After 16 to 20 years of employment, men earned 43 percent more than women, compared with 8 percent more after fewer than five years of employment, and 24 percent more after more than 30 years of work. [5 Reasons Women Trail Men in Science]
Male survey respondents also reported working longer hours than women. Between 25 and 30 percent of the men said they work 50 hours or more per week, compared with about 20 percent of women. But the number of hours worked is just one of many factors that might explain the difference in pay mid-career, the report's authors noted.
The pay difference varied by employer type as well. Men earned more than women at companies, government laboratories, and private labs or research institutes. Men had the greatest advantage at "Other research institutes," where they earned 79 percent more than women. In civilian government jobs, however, men actually earned 11 percent less than women.
Men made up 83 percent of the survey sample. SPIE sent survey invitations to its global customer database in April. The survey yielded a total of 6,752 valid responses.
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