Women occupy just one out of five board seats at S&P 500 companies. There are four companies in the S&P 500 that have no women on their boards of directors: Dentsply Sirona (XRAY - Get Report) , Linear Technology (LLTC) , Concho Resources (CXO - Get Report)  and Transdigm (TDG - Get Report) , according to BoardEx, a business unit of TheStreet.

The presence of women in corporate leadership is positively correlated with firm performance, according to a study from the Peterson Institute for International Economics.

BoardEx data indicates the United States trails a dozen developed countries in the percentage of women on corporate boards, coming in behind Norway, France, Finland, the U.K., Canada and Germany.

This article was written by a staff member of TheStreet.