At A-level, 68.2 per cent of candidates gained two or more passes at grades A-C and 93.8 per cent at grades A-E. Both sets of figures have hovered around 68 and 94 per cent respectively for the past four years.
The Assembly government has consulted on new national targets of at least 55 per cent of 15-year-olds achieving five good GCSE passes in 2007, rising to around 60 per cent by 2010. With results in Wales currently rising roughly one percentage point a year, it may fall short of both goals.
Jane Davidson, education, lifelong learning and skills minister, said: "It is clear that improvements at key stage 4 are slow."
Assembly government strategies for improvement include moves towards a more skills-based curriculum in Wales; better planning for pupil transition to secondary; targeted support for basic skills in literacy and numeracy; reforms of the 14-19 curriculum; and a pound;16 million programme tackling the link between deprivation and low attainment.
She added: "Strategies and policies to improve standards are not quick fixes. It can take years to reap the rewards of excellent work undertaken by our teachers."
GCSE results in Wales continue to lag behind those in England, and are rising at a slower rate. In 2005, the GCSE (or equivalent) pass rate across Offa's Dyke was up 2.6 percentage points to 56.3 per cent. English data for 2006 is not available until October 19.
The Assembly government has previously argued that the figures in England include a wider range of qualifications than the GCSE and GNVQ data used in Wales. This year, for the first time, it has used a wider points score figure reflecting all externally approved pre-16 awards gained by pupils.
Under this system, a grade C in any GCSE full course is worth 40 points, but the points vary for other qualifications. Key skill, NVQ, BTEC and other vocational qualifications are also included.
This new indicator, which should give schools recognition for providing the broadest range of qualifications, shows an average points score per pupil of 333.6 - up from 324.7 in 2004.
Gareth Jones, secretary of the Association of School and College Leaders Cymru, said: "As we go down the road of 14-19 learning pathways, we must recognise and accredit all students' learning and all the courses we are developing."