The first full league tables of the earning power of university degrees has revealed an elite of courses whose graduates go into jobs paying an average of more than £30,000. At the other end of the scale university leavers languish on just £12,000.

The tables, compiled using official data, show Cambridge economics graduates were the highest paid group among last year's university leavers. Six months after graduating they were earning more than £38,000 on average. The next most highly paid were computer science graduates at Imperial College London.

The data will raise questions about whether some of the less well paid graduates have added to their earning power by going to university. The lowest paid include media studies graduates at Teesside University, whose average salary is £13,067, and creative arts graduates at Newcastle on just over £12,000.

The previously confidential figures, released by the Higher Education Statistics Agency (Hesa), show that last year's elite graduates were still able to find well paid jobs in the City despite the slowdown.

They also show that students from new universities earn far lower salaries, particularly in arts subjects. However, there are exceptions. Graduates from some former polytechnics perform exceptionally well when their studies directly related to their careers.

Francis Green, professor of economics at Kent University and an expert on graduate careers, said some differences were caused by regional income variations. But the calibre of applicants attracted by the reputation of particular universities was probably the most significant factor in high salaries. "This is not necessarily the result of value added by fantastic teaching," he said. "Some of these students are really hot, they come in to do their Cambridge degree having already got experience in the financial world in Hong Kong or somewhere. It is a signal of high-level talent."

Previously published salary figures have given averages for each university or each subject across the country. The latest data compare subjects between different universities.

Hesa provided The Sunday Times with average salaries for graduates in 19 broad subject areas — such as social studies, which takes in economics, politics and sociology courses — as well as 16 courses within those areas. Students who graduated last year and found jobs were asked what their salary was six months after graduation.

The "£30,000 club" also covers medical graduates from seven institutions, including Imperial, York, Queen's Belfast and Dundee. Graduates from just five other courses earn an average of more than £30,000 in their first job — business studies at Oxford, mechanical engineering at Imperial College London, maths at the London School of Economics (LSE) and economics at the LSE and University College London.

The figures show wide differences even in similar subjects at similar universities. Biological sciences graduates from Imperial earn £24,000 on average in their first job, 60% more than their Liverpool counterparts.

Last year more than 180 students graduated with Cambridge's world-famous economics degree — one college alone, Trinity, has two fellows who are Nobel prize-winners in the subject.

Kay Tape, 22, who graduated from Sidney Sussex College, Cambridge, last year with a first-class degree in economics, now works for a "big four" accountancy firm and will earn about £50,000 after three years' training.

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