Still, most minority groups hold a smaller share of board seats than their share of the total U.S. population.
Often the investors have found receptive audiences, but slow turnover on corporate boards has limited the pace of change, recruiters say.
The biggest gain over the four-year period was for Black or African-American directors, who nearly doubled their share of board seats to 8.3% from 4.4% in 2019.
They were most represented in the utility sector, with 12% of board seats, and least represented among information technology, energy and healthcare companies, each at 6%.
Compared to Hispanics' total share of the U.S. population, their 3.6% share of board seats "isn't anywhere near where it's supposed to be," she said.