According to a study by Deloitte and The Alliance for Board Diversity, in 2016, women and minorities occupied about 31% of the board seats of Fortune 500 companies—an increase from 25.5% in 2010, and 26.7% in 2012. Despite an increase in diversity, boards are still 79.8% male. This is a slight decrease, however: In 2010, men held a whopping 84.3% of all seats, and 83.4% in 2012.

Overall, 19 black women gained seats on Fortune 500 boards, and black men gained five. White women increased the most out of all groups, with 156 new seats.

Despite gains for women and minorities, it will still take another decade before 40% representation is reached. And that’s only if the pace of change continues, according to the study.

“With the current rate of progress, we aren’t likely to see the number of minorities and women increase to our target of 40 percent representation until the year 2026,” said Ronald C. Parker, the chairman of the Alliance for Board Diversity, told the New York Times. “This is not acceptable. Corporations need to do more to keep pace with the country’s changing demographics.”

Increasing board diversity is made difficult by the fact that only a small number of board seats turn over in any given year, the Times notes, but getting more women and minorities on boards is difficult for another reason: Most companies look to board members with chief executive experience, and chief executives tend to be men.

Interestingly, the Fortune 100—the largest U.S. firms—led representation among women and minorities, where they held 35.9% of board seats. However, this is still a modest increase from 28.8% in 2004, the first year the Alliance began collecting data for the board study. African-American men gained 5 seats, their female counter parts 2, and white women gained 28 seats, the study found.

To conduct the study, researchers analyzed 492 Fortune 500 companies and 5,400 board seats.