International Women's Day today draws attention to a number of issues, especially the persistent statistical gap in the average earnings of men and women.

It has persisted, despite the passage of the Equal Pay Act, ever since women began entering the paid workforce in large numbers in the 1970s.

Equal pay for men and women doing the same job proved not to be enough to close the gap, the fact that women predominate in certain kinds of job, such as nursing, caring and cleaning, became the accepted explanation for the gap and the focus of the search for solutions.

But that view now appears to be challenged by research for the Ministry for Women which published its conclusions yesterday. It finds, according to the chief executive, Margaret Retter, "traditional drivers such as type of work, family responsibilities, education and age no longer explain the majority of the gender pay gap.


"In fact, around 80 per cent of the gap is due to 'unexplained' factors, which the ministry views primarily as behaviour, attitudes and assumptions about women in work, including unconscious bias."

That is quite a ground-breaking change. It comes after years of legal, political and trade union effort to find ways to compare different types of work for the purpose of "pay equity" or equal pay for work of equal value.

A test case taken by the union for aged care has obtained court rulings that the Equal Pay Act 1972 mandates pay equity between different occupations but the rulings said nothing about how different work might be compared.

That task was taken up last year by a working part of Government, union and employer representatives but the technical task largely eluded the working party too.

The best it could suggest was that pay equity claims should be negotiated within the workplace in good faith.

The under-valuation of predominantly female occupations such as aged care still needs attention but if the research done by AUT for the ministry is correct, achieving "pay equity" would remove less than 20 per cent of the income gap between men and women.

The gap calculated to be 13 per cent last year might be reduced to 10 per cent at best. It would leave those "unexplained factors" of behaviour, attitudes and assumptions about women still to be explained.

It must certainly be those factors that appear to be denying women advancement to executive positions and company directorships in the numbers expected. Undoubtedly there is bias and equally undoubtedly, it is subconscious.

Few organisations these days are comfortable with an entirely male team at the top. Even Donald Trump's advisers soon realised that signing executive orders with only men behind him in the Oval Office was not a good look.

But bringing a couple of female staffers in for the picture, or putting a token woman or two on a company board, does little for women and even less for the organisation. Human talents do not have a gender bias.

Organisations that fail to tap the potential of women are denying themselves access to half the human talent pool. That is why it is in everyone's interest that more is done to give women a fair go.