In the last six years, small to mid-size companies with at least one female board member have performed 17% better than those without, according to a study by the Credit Suisse Research Institute. Larger companies performed 26% better. “Stocks of companies with women on boards tend to be a little more risk averse and have on average a little less debt, which seems to be one of the key reasons why they’ve outperformed so strongly in this particular period,” said Mary Curtis, a researcher at Credit Suisse and co-author on the study. The study says 86% of U.S. companies had at least one female board member—up from 73% in 2005. Fifty-nine percent of companies in the global arena had at least one female on the board—up from 41% in 2005.