This has allowed some directors who are approaching retirement age to stay on the board longer, resulting in longer tenures and lower turnover rates. An analysis of S&P1500 by Institutional Shareholder Services shows that companies with longer tenures have fewer women directors.

It’s rare for companies to set term limits for members, only 5% of S&P500 did so in 2018, with a majority choosing 15 years. The average tenure of board members was 8.1 years.

The most effective way to increase gender equality, in addition to actively recruiting women, is to ensure a healthy turnover rate, which includes setting a mandatory retirement age and not raising or abandoning it.

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