Technology company boards are adding more women to their ranks, but gender parity in the field still lags in comparison to other industries.

The percentage of S&P 500 tech company board seats going to women increased from 13.7 percent in 2010, to 18.3 percent in 2014, according to a report by executive compensation research firm Equilar. Across industries, the percentage rose from 15.7 percent to 19.8 percent. Despite the increase, the tech sector still has one of the lowest representations of women, second only to the basic materials industry.

The silver lining: The trend in tech is toward more diversification.

Equilar points to Twitter' plans to fill vacancies with women and minorities and the release of board diversity guidelines by the likes of the California State Teachers' Retirement System and financial planning firm BlackRock.

Apple has also made moves to diversify its leadership, appointing former Boeing CFO James Bell to its board last month. Bell is the only African American on the board.

More tech companies also have more female board members.

Among the 72 tech companies on the S&P 500 in 2014, 29 had boards that were more than 20 percent female. In 2010, 17 tech boards were more than 20 percent women.

The number of tech companies with no female board numbers has also whittled down in recent years, from 15 tech companies on the S&P 500 in 2010 to 5 in 2014.

San Francisco-based internet and phone service company Frontier Communications was the only company Equilar considered to be a tech company that had more than 40 percent female representation on its board.

Editor's note: This post is updated to reflect that Equilar is a research firm.

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