A range of industry and political leaders expressed alarm yesterday at a new study showing the proportion of girls not studying maths for their HSC had more than tripled in a decade, while the number of boys taking the subject had also fallen dramatically.

''I think we have a problem with mathematics study, full stop. This is an economic threat to Australia,'' said Ms Ridout, former head of the Australian Industry Group. ''We're going into this economy where the sciences are going to be more and more important, and it's vital that women have those skills.''

Dr Rachel Wilson, a senior lecturer in educational assessment at the University of Sydney who helped to prepare the report, said if there is not a major cultural shift in the way mathematics is valued, Australia risks falling behind other developed countries.

''If we want to think of ourselves as a smart country, we can't do that without having maths at high-school graduation,'' she said. ''Because at the moment we are the sore thumb sticking out.''

The report showed the number of girls eligible for an ATAR not studying maths in their HSC has climbed from 7.5 per cent in 2001 to 21.5 per cent in 2011.

Roslyn Florie-George is a civil engineering student at the University of NSW and took the most advanced mathematics courses for her HSC. She said it was a great shame so many girls were limiting their prospects for careers in the maths and science industries.

''They are such broad fields so unfortunately they're closing doors to huge, huge opportunities,'' she said. ''I think women with a technical background are invaluable in the workforce.''

Last year Australia's Chief Scientist, Professor Ian Chubb, released a report calling for government intervention to boost participation in science, technology, engineering and maths.

In response, the federal government committed $22.5 million for the Australian Maths and Science Partnerships Program to make science and maths more engaging for young Australians.

Roslyn Prinsley, the federal government's new National

Science and Mathematics Education and Industry Adviser, said she had already been contacted by organisations, including the Australian Bureau of Statistics, who said they can't get the mathematicians they required.

''In our technology-based world, everything we do involves maths, most jobs require quantitative skills, most science requires quantitative skills,'' she said.

Experts have also warned the falling rates of girls studying mathematics risked cementing the existing gender pay gap.

''It's going to perpetuate the underepresentation of women in the finance industry … and in areas like engineering, which has been really hard for women to break into,'' Ms Ridout said.

The NSW Minister for Women, Pru Goward, a former federal sex discrimination commissioner who also studied economics at university, said the findings of the University of Sydney study were ''very depressing'' and encouraged girls to stick with maths. ''They don't know they're limiting their options,'' she said.

The median gap in starting salaries doubled last year, rising from $2000 in 2011 to $5000 in 2012, the Workplace Gender Equality Agency said.

Few university courses have mandatory pre-requisites but mathematics is ''assumed knowledge'' for a range of degrees. At the University of Sydney, these include bachelors of commerce, architecture, economics, information technology, medical science, pharmacy and science.

Mathematics extension 1 is assumed knowledge for most engineering courses.