According to the Quarterly Employment Survey, men earned an average hourly rate of $29.20 during the September quarter - compared with the $25.06 earned by women.
The $4 difference translates to a 1.3 per cent jump in the gender pay-gap since the last September quarter, from 12.85 per cent to 14.18 per cent.
"I think for a long time women's roles have been undervalued in companies," Mr Radesic said.
But this was beginning to change. "If you look at infrastructure, forestry, manufacturing - there's a good mix of females in those sorts of roles."
Margaret Noble's appointment as Waiariki Institute of Technology's chief executive this year was another good example, Mr Radesic said.
Rotorua business consultant and well-known public speaker Deb Bell said she had experienced the gender gap herself and put it down to a number of things.
"I do not believe there should be a gender gap. However, I do believe women need to be more assertive and improve their negotiating skills so they feel confident presenting their case when negotiating their employment package," she said.
"I also think women are so busy or so pre-occupied with doing the best they can for others they don't always do the best for themselves. I think that comes from being mothers and carers."
Mrs Bell said this did not mean it made it okay for businesses to exploit women when it came to their pay. She said another issue was the low percentage of women on boards of trustees and boards of directors in big businesses.
University of Canterbury Professor Lucy Johnston said outdated stereotypes of women in business often made things worse in the workplace. "Role models and encouragement are essential for young women and we must make every effort to promote and endorse successful women and we must ensure that to become successful, women do not need to become like men."
University research indicated women were often outdone by men when competing for jobs typically filled by males, despite having the same level of experience and qualifications.
It also found women were more likely to be successful in such job applications if they dressed and talked in a more masculine way, Professor Johnston said.
This year, it was also revealed that female accountants are paid, on average, 26 per cent less than their male counterparts, according to the annual New Zealand Institute of Chartered Accountants survey.
The NZ Federation of Business and Professional Women labelled the pay gap figures "legalised theft". Closing the gender pay-gap would help all New Zealanders.
"It is a no brainer that if more money was in the pockets of women and their families, then the economy benefits and grows," president Carolyn Savage said.
"Equal pay for work of equal value should be rewarded on the same financial basis which in turn would result in more buying power for women and their families."
According to the quarterly survey rates, women would need to work until the February 21 next year to earn the same as their male counterparts did by the end of 2012, Mrs Savage said.
Employers and Manufacturers Association spokesman Gilbert Peterson said women were under-utilised in the New Zealand workforce.
"We're firmly of the view that a way for business to improve their productivity is to look at getting more diversity in their workplace.
"As far as we're concerned, women are under-utilised in our businesses and that's reflected in the pay gap," he said. "It's an opportunity that's going begging."
Equal Employment Opportunities Trust general manager Bev Cassidy-Mackenzie said businesses needed to implement systems to ensure discrimination against women and other groups did not occur.
