The number of “good” schools keeping their rating or improving to “outstanding” following Ofsted inspections has fallen for the first time in five years.

Figures released by Ofsted today show that almost a quarter of all secondary schools previously rated as “good” that were inspected in 2019-20 declined to grades of either “requires improvement” or “inadequate”.

Ofsted introduced a new framework last September, putting more focus on assessing whether a school has a “well-designed and ambitious curriculum, and whether it has the same high ambition for all pupils”.

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The latest report states: “Between 2014/15 and 2018/19, the proportion of previously ‘good’ schools remaining ‘good’ or improving to ‘outstanding’ increased each year. This year, there has been a decrease of one percentage point from 87 per cent last year to 86 per cent this year.

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“We have carried out 1,573 section 5 and section 8 inspections of previously ‘good’ schools this year. Of these, 84 per cent remained ‘good’, 3 per cent became ‘outstanding’, 11 per cent now ‘require improvement’ and 2 per cent became ‘inadequate’.”

The document also states that all routine inspections and the publication of inspection reports were suspended in March 2020 due to Covid-19, and that some inspections were therefore excluded from the figures.

However, it says the suspension has had “a minimal effect” on the overall grades or messages included in today’s publication.