The claim

Shadow treasurer Chris Bowen put the case for gender equality in a speech to the Women's Economics Network.

He argued that efforts to tackle gender inequality had made "far too little progress", while the gender pay gap had been "in neutral for 20 years".

And it wasn't, he said, because women were less educated or had fewer skills than men.

"While Australian women's educational attainment has steadily increased over the past two decades, the gender pay gap hasn't budged," he said in a speech hosted by KPMG in Sydney on June 26.

Is it correct that over the past two decades, more women have become highly educated, yet the gap between men's and women's average weekly full-time pay has barely changed?

RMIT ABC Fact Check investigates.

The verdict

Mr Bowen is correct.

Over the 20 years to 2016, the gender pay gap in Australia has hovered between 15 per cent and 19 per cent.

It currently sits on its 20-year average of 16 per cent.

During the same period, women's educational attainment has steadily risen.

The proportion of Australian women with a bachelor's degree or above rose from just under 13 per cent in 1996 to 28 per cent in 2016.

In fact, since 1998, more women than men have earned a bachelor's degree or higher qualification.

This appears to have had little impact on the gender pay gap.

What is the gender pay gap?

The gender pay gap is not the same as unequal pay.

It is the difference between the average wages of men and women working full-time, and can be measured in different ways, but Australia's Workplace Gender Equality Agency (WGEA) generally measures it as the difference between women's and men's average weekly full-time equivalent earnings, expressed as a percentage of men's earnings.

Unequal pay is different: it is when men and women doing the same work are paid different amounts on the basis of their gender – and that's illegal.

So, for example, if there are more men at the top of an organisation, while women are concentrated in its lower ranks, a gender pay gap will exist, but this disparity does not necessarily indicate unequal pay.

The WGEA is the Australian Government statutory agency charged with promoting and improving gender equality in the workplace.

It reports to the Minister for Women, and is authorised to collect data from all non-public sector employers with more than 100 employees, which accounts for more than 40 per cent of the Australian workforce.

The authority calculates the national gender pay gap using Australian Bureau of Statistics trend data for full-time adult average weekly ordinary time gross earnings.

Fact Check has used the same figures to show the narrow band within which the national gender pay gap has hovered over the past 20 years.

Average full-time weekly earnings by gender over time.

The gender wage gap over the last 20 years.

Experts consulted by Fact Check were unable to provide a definitive explanation for why the gap closed to 14.9 per cent in 2004.

However, given that changes in the gap generally reflect economic cycles, they said the peak of 18.5 per cent in 2014 was likely the result of the mining boom (mining being an industry typically with a high concentration of male workers).

The national gender pay gap is an imperfect measure, but it is a strong indicator of the overall position of women in the workforce.

ABS figures show that in 2016, on average, men in full-time work earned $1631 a week while women earned $1369.70.

With an average $261.30 less in their pay packets each week, women were earning just 84 per cent of the average pay for men.

What are the drivers of the gender pay gap?

According to the WGEA, Australia has a highly gender-segregated workforce.

This means there is an unequal distribution of men and women in certain occupations and industries.

It also refers to the tendency of men and women to study different fields and to be unequally distributed across part-time and full-time work.

In 2015-16, six in 10 people worked in an industry dominated by one gender.

Or, as one parliamentary report has put it: "60 per cent of Australian workers don't know what it is like to work in an industry with balanced gender representation."

The June 2017 report of a Senate committee that investigated gender segregation in the workplace and its impact on women's economic equality attributed this uneven distribution to individual workers' choices being constrained by structural factors and social norms.

Carer responsibilities, carried largely by women, as well as opportunities for part-time work and flexible working arrangements, all conspire to funnel women into particular industries and sectors.

Traditional gender roles and expectations also influence the subjects that young men and women study in schools and universities, ultimately affecting career choices.

"Segregation is one of the major sources of the gender pay gap," the report says.

"Taken together, occupational and industrial gender segregation are the second most significant contributors to the pay gap between men and women, after sex discrimination."

A woman working in a female-dominated industry would, on average, earn almost $40,000 less in total remuneration than a man in a male-dominated industry, it says.

Drawing on research by the WGEA, the report highlights two types of segregation: "deeply entrenched" horizontal segregation, which refers to the over-representation of women and men in certain occupations or industries, and vertical segregation, which refers to the imbalance between women and men in leadership positions (leadership roles are dominated by men, while women are concentrated in non-management positions).

The WGEA's 2016 analysis found women dominated in healthcare, education and retail, while men dominated in mining, construction and utility services.

In terms of types of work performed, women were more likely to work as clerical and administrative workers, or community and personal service workers, while men were more likely to be trade workers or technicians.

In its submission to the Senate inquiry, the WGEA points out occupational gender segregation is linked to wage inequality, as women's work has historically been undervalued and female-dominated industries and jobs attract lower wages than those dominated by men.

KPMG calculated that industrial and occupational segregation together accounted for 30 per cent of the gender pay gap in 2016.

However, sex discrimination remained the biggest contributing factor at 38 per cent.

The table below provides a breakdown of the pay gap by contributing factor.

Contributions of different factors to the gender pay gap. ( HILDA, KPMG )

Academics have sought to analyse the extent to which various different factors impact the gender pay gap.

Macquarie University's Dr Ian Watson studied the gap among managers and found somewhere between 65 per cent and 90 per cent of it could not be explained by the characteristics of managers and was possibly due to discrimination against women.

"One is left with the stark conclusion that the major part of the gap is simply due to women managers being female," he wrote in a 2010 paper.

Indeed, as the senate report points out, women are not merely entering professions that historically have been feminised and undervalued; the professions themselves become less valued and less well paid as more women enter the field.

Women's educational attainment

Over the past couple of decades considerable changes have taken place.

Significantly, there are more women in the workforce.

Over the past 40 years, their work participation rate has risen from 45 per cent to 60 per cent, according to the Department of Employment's analysis of ABS data.

As well, women's levels of education have increased.

The proportion of women with a bachelor's degree or greater rose from just under 12.7 per cent in 1996 to 28 per cent in 2016.

This compares to the proportion of men achieving such levels having risen from 13 per cent in 1996 to 24 per cent in 2016.

The graph below shows that, since 1998, women have outnumbered men graduating from higher education.

Despite this, female undergraduates earn significantly less than male undergraduates.

According to the 2016 Graduate Outcomes Survey, the median starting salary of women and men were $56,400 and $60,000 respectively.

The survey reports that women are more likely to graduate from study areas that receive lower levels of remuneration.

But beyond subject choice, the gender gap in median male and female graduate salaries persists due to a range of factors such as occupation, age, experience, personal factors and possible inequalities within workplaces.

Besides greater workforce participation by women and their attaining higher educational levels, other significant societal changes have been at play, including greater provision of child care and legislation providing for paid parental leave and more flexibility in working arrangements. Yet, the national full-time gender pay gap persists.

Are we the worst in the world?

By international standards, Australia's gender pay gap at 16 per cent is not the worst but it is higher than the OECD average of 15.1 per cent.

Among OECD countries, Korea has the greatest gender pay gap at 36.7 per cent and Belgium the lowest at 3.3 per cent. Gender pay gaps are narrowing in most OECD countries, but Australia was one of four countries where the gap widened from 2012 to 2014. (The others were the Czech Republic, Estonia and the Netherlands).

In Australia, there is currently no specific national target for reducing the gender pay gap.

Sources