The proportion of exams taken in which Welsh students gained at least an E-grade (pass) rose by only 0.1 per cent to 96.5 per cent this summer, compared to 96 per cent for the UK as a whole. The proportion of A-grades increased by 0.5 per cent, to 23.5 per cent - 1 per cent more than the UK-wide figure. However, unions, exam experts and angry students dismissed the annual litany of claims that the A-level gold standard has been eroded by “grade inflation”.

Emily Blewitt, a student at Coleg Sir Gar, Carmarthenshire, who hopes to study English at Oxford university, said the argument was insulting. “I really resent it when people say every year that A-levels have got easier and I think it is a direct attack on my hard work. I don’t know what they were like in the past but what I do know is that I have worked hard and it’s not been easy at all,” she said.

Brian Rowlands, secretary of the Secondary Heads’ Association Cymru, said people had been claiming standards were falling since he matriculated 50 years ago. “We are getting fed up with the constant carping that goes on about these results each year,” he said.

Welsh students took 35,206 A-levels this summer, with young women accounting for an increase of nearly 500 on last year. Most of the entries (64 per cent) were with the WJEC, the Cardiff-based exam board.

Maths students in Wales gained the highest percentage of A-grades at 40.1 per cent. But the biggest increase in A-grades was in French, up from 29.8 to 32.8 of exam entries. The most popular subjects in Wales were English, history, biology and maths.

Gareth Pierce, chief executive of the WJEC, the Wales exam board, said that the A-level pass rate in 1995 was around 85 per cent - very similar to this summer’s AS pass rate of 87.5 per cent in Wales.

“The overall pattern of results shows very considerable stability. The very high pass rates in some subjects reflect the fact that students know from the AS results obtained during the first year of their A-level studies what their prospects are for success over the full programme of study,” he said.

“Students are therefore able to take informed decisions regarding their second-year studies and are unlikely to continue with a subject where their AS results are not satisfactory.”

Pass rates at AS actually fell slightly this year, by 0.2 per cent in Wales. The proportion of A-grades was also down, by 0.4 per cent to 17.9 per cent.

Gareth Matthewson, former national president of the National Association of Head Teachers and head of Whitchurch high school, Cardiff, said students usually knew early on in their AS-studies which subject they would drop at A-level, and then focused on their stronger areas of study. As a result, AS-levels had failed to broaden the curriculum sufficiently, he argued.

“We were all in favour of broadening the curriculum for sixth-formers, but AS-levels haven’t been a great success. We need the Welsh baccalaureate changes to come online as that makes sure every subject students study has some relevance towards their final diploma,” he said.

Jane Davidson, Assembly education minister, said: “Estyn has said that the standard of teaching in Wales has never been higher and this has translated into better pupil performance.

“The young people who have done well have worked harder to do better than ever before. It is to their credit,” she added.