Workplaces are being urged to nurture the talents of young women to enter senior management roles.
Thursday was officially International Women's Day, a time to reflect on the achievements of women in society, business and life.
A survey of 40 countries by Grant Thornton International looked at the number of women holding top positions.
The study found New Zealand women hold 28% of senior management positions, down from 32% in 2011 and 31% in 2004.
Grant Thornton spokesperson, Pam Newlove, says the fall could be due to not enough mentoring of female employees.
She says a number of very senior public roles were held by woman in the mid-2000s and people may not have realised how much work would be needed to bring the next generation of women leaders through into senior roles.
Ms Newlove says the progression doesn't happen by accident, and it's about senior women already in those roles mentoring the next generation to come through.
This already happens informally, she says, but probably not as frequently as needed and probably doesn't have as much visibility at senior management and board level in an organisation.
EU considers mandatory quotas
In Europe, Italy ranks highest with 36% of women in senior roles, while Japan lags behind in Asia - employing 5%.
While Italy is bucking the trend, the European Union says companies are still too slow in promoting women into decision making posts, and it could introduce mandatory quotas for women on corporate boards later this year.
Last year, EU justice minister Viviane Reding called on European companies to voluntarily ensure 30% of their board members are women by 2015.
So far just 24 companies have signed that pledge, and just one in seven board members at Europe's top firms is a woman.
A professor of social and organisational psychology at the University of Exeter, Alex Haslam, says there are plenty of capable women directors to fill the spots, but companies appear resistant to change.
He says there's evidence that getting women into company boards has a positive impact on company outcomes.
Professor Haslam says the EU policy is correct and the empirical data for this is convincing.
The European Commission says women make up 27% of boards in the largest Finnish companies and 26% in Latvia, but only 3% in Malta and 4% in Cyprus.
Belgium, France, Italy, the Netherlands and Spain are among the countries that have introduced gender quotas for companies.