The only industry where women are paid more is Forestry and Mining where men earn 32c less.
Spokeswoman for the Pay Equity Coalition, Angela Mcleod, said the divide was deepening because women were increasingly taking part-time work after losing full-time employment under a harsh economic climate.
It's also an indicator of women being in minimum wage positions in the care and retail sectors.
"People see that it's okay because it's a traditional woman's role to be a carer, so we don't have to pay them that much because they would normally do it."
A campaign to get Green MP Jan Logie's bill, which aims to introduce a framework to ensure transparency around equal pay, into Parliament began in November seeking to close the 10 per cent gender pay gap.
A voluntary code has already been introduced to increase female representation on boards.
"There's an economic benefit to a family, to the community and to the national economy. I'd hate to think that it was just discrimination, but I just don't see what the problem is," Mrs Mcleod said.
Research undertaken by the Ministry of Women's Affairs in 2007 showed a 6 per cent gender pay gap for graduate starting salaries, increasing to 17 per cent after five years.
The Employers and Manufacturers' Association (EMA) blamed the difference in pay on choices "freely made" in society; when men and women jointly decide which partner will take time off for child-rearing, work part-time rather than fulltime and choose 9am-5pm work.
"Until our blokes are prepared to stay home as much as our women to raise their children, a gender pay gap is likely to remain," spokesman Gilbert Peterson said.
These choices were also affected by women preferring to take English, media studies and Spanish at school rather than maths and physics, which led to different professions.
First Union general secretary Robert Reid said the private sector in general does worse in the gender pay gap than the public sector, and finance is no exception.
"There is clear occupational segregation in [finance]. Women work in largely front line and low-to-middle management roles, and men dominate in the very senior management, and excessively paid, roles."