The number of skilled job vacancies being advertised online has fallen again, new figures show.

The Internet Vacancy Index (IVI) covers all occupations, across all skill levels and is based on a count of online vacancies newly lodged on SEEK, My Career, CareerOne and Australian JobSearch.

The Department of Education, Employment and Workplace Relations (DEEWR) report reveals that the index decreased by 3.1 per cent in July 2012 in trend terms.

Over the year, the index has fallen by 15.6 per cent and is now 48.0 per cent below the March 2008 peak.

In the last year, the strongest falls were recorded for clerical and administrative workers, down by 20.4 per cent, followed by labourers, down by 18.1 per cent.

These latest figures will be a cause for concern for skilled Irish job hunters, as vacancies continue to decrease.

Job vacancies that are considered plentiful in Australia, such as construction, ICT, nursing and engineering, have also decreased over the last year by 25.5 per cent, 24.6 per cent, 9.6 per cent and 6.5 per cent, respectively.

The only occupational groups to escape unscathed are Science Professionals and Vets, which includes geologists and geophysicists, who recorded an increase of 8.2 per cent.

Victoria has suffered the biggest decline in vacancies, with the index plunging 20.8 per cent in the year up to July 2012.

In comparison, the job market in Western Australia has remained somewhat steady, recording a 4.3 per cent decline in skilled vacancies in the last year.

The regional index increased in six of the 38 regions over the year to July 2012.

The Pilbara and Kimberly regions in Western Australia enjoyed the greatest growth, increasing by 9.3 per cent, while NSW North Coast and Bathurst and Central West NSW recorded the strongest falls, declining by 30.4 and 29.9 per cent respectively.