More Welsh schools are performing well, according to the Welsh government's National School Categorisation system, which rates schools by placing them into colour-coded categories.
Some 333 primary and secondary schools were rated green in 2015, which is the best possible category. This is up from 236 one year earlier.
There are four categories overall: green, yellow, amber and red. A green rating indicates a high level of learner outcomes, resilience at all levels and attempts to move towards or sustain excellence.
Schools that are categorised as red have seen a decline in key performance areas and may require intervention from local education authorities.
Education minister Huw Lewis commented: "This is not about crude league tables or labelling schools - it is about directing the right support to schools that need it and ensuring improvements right across our school system. Ultimately, it is about raising standards and supporting our schools to self improve."
He added that the system delivers benefits for pupils, as schools are not judged on their top performers alone. It is impossible for schools to receive a green rating if their students who receive free school meals are not performing to a minimum standard.
Earlier this month, Mr Lewis revealed he will not be seeking re-election to the Welsh Assembly's election in May.
His decision has been met with a surprise and a degree of uncertainty about what it could mean for education in Wales.
Owen Hathway, Wales policy officer for the National Union of Teachers, told ITV: "I think in some sense, there's a little bit of concern that we're in a stopgap between now and the election."
However, he added that he has no doubt Mr Lewis will continue to do the job to the best of his ability until he steps down in May.