Released yesterday, the report shows the state as the worst performer in the nation in regard to retention rates collected from school census data from 2002 to August 3, 2012.

Between 2002 and 2012 the retention rate of year 10 to 12 students across all public, independent and Catholic sectors dropped from 75 per cent to 67.1 per cent - a 7.9 per cent decline.

It is almost double that of the next worst-performing state or territory, the Northern Territory, which saw the retention rate worsen by 4.1 per cent.

Victoria and the Australian Capital Territory also showed a decline over this period but by a much smaller margin.

Education Minister Nick McKim said the statistics were "disappointing" and labelled retention as a "complex problem" with no easy solution.

"Tasmania has the most rurally dispersed population of all Australian states and has a high level of socio-economic disadvantage," Mr McKim said.

"The department is considering responses to a paper into extending year 11 and 12 into regional areas, and the department will have a report to me by the end of the month."

Opposition education spokesman Michael Ferguson said the latest results were not good enough.

"It is bad enough that we continue to be the worst state in Australia when it comes to year 10 to 12 apparent retention, but it is inexcusable that we are falling even further behind," Mr Ferguson said.

The Liberals' plan to extend high schools to year 12 would address the problem. "We must get rid of the ongoing perception that high school ends at year 10," he said.