The number of primary school children in Brighton and Hove making good progress in reading, writing and maths has dropped during the last 12 months, after the government changed its tests.
In 2015, 82 per cent of 11-year-olds reached Level 4 in the SATS tests.
However, after a government shake-up designed to make the tests more challenging, Brighton and Hove has seen only 58 per cent achieve the expected standard.
Headteachers have made a string of criticisms about the changed tests.
The National Association of Head Teachers has dismissed the results as ‘not worth the paper it is written on’, pointing to delayed guidance for schools, mistakes in test papers, and answers being accidentally published online.
While all education authorities saw their overall figures drop, Brighton and Hove saw it go up in the rankings compared to other authorities. In 2015 the county was 55th out of 152 councils, but this year was 37th.