Male executives earn a staggering 33% more than their female counterparts. And even when controlled for factors like years of experience, education, skills, management responsibilities, and company size, the gap remains at 6%, according to PayScale’s report, which collected data on 1.4 million full-time employees between July 2013 and July 2015.

Men and women who have no management responsibilities have the narrowest controlled wage gap, at 2.2%.

Even when a women has a mentor or higher-up looking out for her, the wage gap persists. While both men and women who have been recommended for leadership training earn more money than their counterparts who have not, men see a greater pay increase than women. Among those who have been targeted for the manager track, the wage gap is 3.3%; among those who have not, the gap is only 1.6%.

And just as being a workplace leader doesn’t close the gap, neither does more education.

The controlled pay gap between a woman who holds an associate degree and her similarly credentialed male colleague is 2.2%, the smallest of any male-female peer groups.

Women who’ve earned a doctorate face the highest controlled pay gap (5.1%), followed by MBA graduates (4.7%) and those who have earned medical degrees (4.6%).

Surprisingly, women who opt to study at some of the nation’s most well-regarded schools also reported the biggest controlled pay gaps relative to their male peers. Ivy league graduates have a 4% controlled gender wage gap and a 28.7% uncontrolled gap. By contrast, graduates of art and design schools are tied with those of engineering schools for the lowest controlled gender pay gap, 1.9%.