Fewer than one in five companies have specific objectives to address the gender pay gap, according to a landmark report which also revealed female representation in Australian management positions remains low.

The Australian “gender equality scorecard”, compiled by the federal government’s Workplace Gender Equality Agency (WGEA), pulled together data from 11,000 companies in Australia, covering 4m employees. The data is based on the first year of standardised gender reporting to the WGEA.

It found a steady decline of women in key management positions when moving up the ranks, with more than a third of companies having no women at all in key management positions. Just 17.3% of CEO positions in Australian companies were held by women.

Despite these statistics and recent pushes to address the inequality, fewer than 25% of employers have done any analysis to see if there is a problem in their workplace with gender pay equity. The most common course of action was to review individual remuneration outcomes.

Fewer than half of all employers have a remuneration policy or strategy in place, and only 18.1% of companies have any specific objectives to address gender pay equity, which the report said suggested “many organisations don’t take a disciplined approach to setting pay levels.”

“Gender bias is likely to creep into pay decisions when employers have a loose approach to remuneration. This leads to unequal pay outcomes for women doing the same or comparable work as men,” said WGEA director Helen Conway.

Even if a policy was in place, there was often no strategy to see it followed through. The report found 47.7% of employers had flexible working policies but only 13.6% had a strategy.

Similar numbers apply for supporting employees with family and caring responsibilities.

Conway told Guardian Australia that while there are “well intentioned” employers “they’re often doing work that is not strategically based.”

“Initiatives are often on an ad-hoc basis but … what we’re saying is we recognise employers are trying in this space but they need to do more and be more effective,” she said, pointing to the gender strategies toolkit, also launched on Tuesday.

The statistics were much better for policies relating to sex-based harassment and discrimination, particularly in larger companies with more than 5,000 employees. More than 96% of employers had some kind of policy or strategy in place, most encompassing some kind of grievance process.

However, fewer than a third of companies had a domestic violence policy or strategy in place to address domestic violence, and they are generally more generic services such as counselling.

“There’s still a lack of appreciation in the community generally and in workplaces about how pervasive domestic violence is and the impact it has on individuals and workplaces,” said Conway.

“At least from the employer’s perspective, the impact on productivity can be substantial so you need to take a strategic approach to this, how to deal with the impact on employees and businesses.”

Women make up 48.5% of the workforce but their ranks include a much larger proportion of casual and part-time employees. Only 35.8% of Australian full-time workers are women.

In an examination of numerous management levels, the ratio of women to men was only higher in sales, community, personal service and clerical and administrative roles.

The positions of chair and CEO were dominated by men, with between 76% and 100% representation across different industries.

Across all positions, the industries with the lowest number of female employees were mining and construction, with 15.7% and 16.1% respectively.

While the financial and insurance services industry had one of the highest female representations in its workforce (56.1%) and an above-average percentage in managerial positions, it also had the largest pay gap of 36.1% in total remuneration.

World leaders at the recent G20 summit in Brisbane committed to reducing the gender participation gap by 25% before 2025.

“This has the potential to bring 100m women into the global workforce,” said the prime minister, Tony Abbott, at the time.

“An extraordinary achievement if we can deliver on this, but it is a clear aspiration and it is an achievable accountable goal.”

Conway told Guardian Australia the goal was “lofty” and “we now need to see what actions various countries will now put in place to achieve that objective.”

“Here in Australia the work is currently being done to ensure we can meet that target so that is encouraging.”

Women who work for companies with more than 100 people on average earn 24.7% less than their male colleagues.

The opposition spokesman for employment, Brendan O’Connor, said increased workforce participation was important, including a primary focus on assistance with childcare. O‘Connor disputed that the Abbott government’s proposed paid parental leave scheme would address it, “because that is an inequitable, non-means tested approach to providing support.”

“What we would suggest is a combination of the paid parental leave that Labor introduced, proper investment in childcare and indeed other areas of public policy,” he told Sky News.

“Such as making sure that the co-contributions continue to be paid so they don’t have to worry about their retirement, making sure that you do not deregulate the higher education sector to the extent that university fees double. That will actually prevent women from joining the workforce.”

Conway said the data was indicative of what was already known but the report provided “granular detail” to drive change.

“This data shows us what the issues are at every level,” Conway told ABC News 24.

“Women are getting jammed. So the very significant cultural and structural issues in workplaces need to be addressed immediately.”