Some 75% of today’s most popular tech jobs have gender pay gaps above the US national average of 5.4%, according to new research from Glassdoor.

When controlling for workers’ age, education, experience, occupation, industry, location, company, and job title, the adjusted gender pay gap in the tech field was 5.9% in the US, the report found.

“To ensure an apples-to-apples comparison of men and women in the tech sector, we statistically controlled for as many important differences between workers as we could,” Andrew Chamberlain, chief economist at Glassdoor, wrote in a post about the results. “That allows us to carefully assess whether there is a real gender pay gap in tech roles, once we’ve ‘adjusted’ for similar male and female workers.”

The data is based on 504,438 salary reports shared on Glassdoor by US-based, full-time workers as of November 2015.

SEE: Closing the tech gender gap: How women can negotiate a higher salary

The tech industry reveres high competency, said Emily Amanatullah, research fellow at Georgetown University’s Women’s Leadership Institute. Yet decades of research has shown that women are assumed less competent in technical domains relative to men, and that women are held to higher expectations of competence (for example, women and men with equal qualifications are not perceived equally, and a woman needs to have more experience/qualifications to be seen on the same level as a less qualified man).

Women who do overtly demonstrate their competence are penalized for violating gender role expectations, Amanatullah said. “So ultimately women are caught between a rock and a hard place which keeps them out of ascending to the highest paid positions,” Amanatullah said.

In terms of this research, the biggest issue is access to the higher paid positions, Amanatullah said. “Women are disproportionately represented there because of the structural and implicit gender bias that keeps them out,” she said. “So it is important to gauge the wage gap by comparing apples to apples, but it’s also important to look at why women are funneled into the apple basket instead of being given an equal chance of competing with the oranges.”

The wage gap seen here is likely due in part to the fact that women are often not hired by the highest-paying tech companies, said Ariane Hegewisch, program director of employment and earnings at the Institute for Women’s Policy Research. Other factors include increased competition for jobs at the top tech firms from both US and international candidates, and the number of hours women work, she said.

Managers can ensure their company does not have gender wage gaps by first auditing their payroll information, and seeing if there are discrepancies between male and female employees that cannot be explained by position or skillset, Hegewisch said.

Businesses can also implement transparency policies–it might not mean displaying what every employee earns, but rather the pay ranges for each position, she said. Companies should also set out criteria for success, and expectations for promotions.

Here are the 16 most popular tech roles that had the largest pay discrepancy, according to Glassdoor data, and the adjusted gender wage gap for each position.

1. Computer Programmer

Gender wage gap: 28.3%

2. Game Artist

Gender wage gap: 15.8%

3. Information Security Specialist

Gender wage gap: 14.7%

4. Software Architect

Gender wage gap: 10.6%

5. SEO Strategist

Gender wage gap: 10.2%

6. Front-End Engineer

Gender wage gap: 9.7%

7. Database Engineer

Gender wage gap: 9.7%

8. SharePoint Developer

Gender wage gap: 9.2%

9. Systems Technician

Gender wage gap: 8.3%

10. Data Analyst

Gender wage gap: 7.2%

11. Systems Administrator

Gender wage gap: 6.8%

12. Software Engineer

Gender wage gap: 6.0%

13. Programmer Analyst

Gender wage gap: 5.2%

14. Product Manager

Gender wage gap: 4.3%

15. Mobile Developer

Gender wage gap: 2.9%

16. Hardware Engineer

Gender wage gap: 1.9%