"The results are disappointing and show there is some way before the glass ceiling is cracked in the board room," said Harriet Steel, head of business development for Hermes, in a press release.
Research by the Davies Review released in March found that, in the U.K., women made up 23.5 percent of the board for FTSE 100 companies and just 8.6 percent of executive directors were female.
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"The reality is the diversity argument still has less resonance for many companies. Senior management can often see diversity as a legislative chore, or simply another compliance target to be met," explained Steel.
"This is less institutional sexism or racism, but more a failure to recognise why diversity is important and the advantages it brings to a business."
These advantages include better governance and greater stability.
For instance, a report by the International Monetary Fund last month found that banks with more female board directors achieved better stability and more barriers to earnings shocks.
Steel added that gender diversity, as well as racial and ethnic diversity, were crucial to preventing "group think" culture
"The perils of this type of culture have been seen in corporate scandal after corporate scandal – Enron, Barings, sub-prime loans, the banking crisis, to name just a handful," she said. "It may be convenient for the members of a board to think in the same way, but it is rarely good for business".