New Zealand ranked fourth in PwC's Women In Work index
New Zealand could add more than $16 billion to the economy by lifting its female employment rate to match that of Sweden.
New Zealand has been ranked fourth in PwC's Women in Work Index, coming in behind Iceland, Norway and Sweden.
The report, based on data from 2014, highlights the potential gains for businesses and economies by employing more women and shrinking the gender pay gap.
If New Zealand raised its female employment rate to match Sweden's - the country with the highest female employment rate in the OECD - it stands to grow GDP by almost 7 per cent, or US$11 billion ($16 billion), the report says.
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New Zealand's ranking remains unchanged from 2013; however, it has risen four places in the past 14 years.
Meanwhile, Australia continues to fall in the index rankings, dropping from 17th to 20th.
According to the report, New Zealand's gender pay gap is not as large as those of some of the OECD's worst-performers.
Kiwi men's median wages were found to be 6 per cent higher than those of their female counterparts, compared to a gender pay gap of 17 per cent in the US and 18 per cent in the UK.
However, the Ministry for Women puts New Zealand's gender pay gap at almost 12 per cent for 2015 (9.9 per cent in 2014) and the Young Women's Christian Association (YWCA) puts it at 14 per cent.
YWCA chief executive Monica Briggs said International Women's Day was the perfect time to advocate for equal pay and equal work.
Businesses should reflect on what more they could be doing to address the gender pay gap, Briggs said.
"There is, however, a growing force for change. With legal challenges around pay equity coming from a number of different quarters now, businesses need to change their thinking and their attitudes in order to maintain a competitive advantage."
The PwC report said significant gains had been made across the OECD to improve female economic empowerment.
More women were in work than ever before and unemployment rates had gradually declined following the 2008 global financial crisis.
"However, the gender pay gap remains unacceptably wide – women are still paid $83 for every $100 her male counterpart earns on average across the OECD."
PwC New Zealand partner and diversity and inclusion leader Leo Foliaki said the workforce was growing in New Zealand, not just in numbers but also in the diversity of its people and their skill sets.
"Businesses must adapt their models to fully harness this talent and to be competitive internationally," he said.
Underemployment of women also remained a pressing issue.
In the UK alone, 1.5 million women would like to work more hours but did not have the opportunity to do so.
Foliaki said this meant there were significant opportunities for flexible work practices to better leverage the skills of women returning to the labour market.
This was a particular issue for more senior positions, where there was an undersupply of flexible roles.
The concentration of part-time work outside of high-level jobs increased the tendency for women to work in occupations below their skill levels, he said, adding that there was a clear business case for greater flexibility in the workplace.
"To continue enabling the success and evolution of all our people, we needed to move on from our past ways of working."
Businesses should focus on flexibility and equipping people to work from any location, using any device, at a time that suits them and their clients.