The news that most 11-year-olds who fail to reach the target level in tests have special needs is in line with official reports going back 30 years.
In 1978, the Warnock inquiry, the first major study of what were then called "handicapped" children, said about one in five pupils would have some form of special educational need. At any one time, one in six would require special provision, it said.
The latest statistics suggest that in Year 6 the higher figure of about 24 per cent of pupils either have a statement, or are classed as SEN but do not need a statement.
Do the figures offer proof of the difficulty schools face in ensuring higher proportions of their pupils reach level 4, the Government's target in English, maths and science for 11-year-olds?
If it is difficult for a child with special needs to reach it, and almost one in four now has special needs, then expecting more than four out of five children to reach the target level will be tricky.
Sceptics admit there are two problems with viewing this SEN data as categorical evidence of the success or otherwise of the schools that educate these children.
First, it is claimed that SEN is such a broad term that it is hard to be definitive about the ability levels of pupils. This point was made in a 2006 report by the Commons education and skills select committee, which said that categorising children as SEN and non-SEN was an "arbitrary distinction".
In fact, special needs embraces many categories, including children with autism, those with visual and hearing impairments, dyslexia, learning difficulties and behavioural problems.
While many such children might struggle to meet the Government's test benchmark, it is not clear that all will.
Second, some argue that there is a sense in which the link between special needs and relatively poor test performance could be circular.
As TES columnist Huw Thomas says on page 19, a child who is underperforming at a young age seems more likely to be identified as SEN because of this. Thus, poor test performance might lead to a child being categorised as SEN, rather than the special need explaining the poor performance.
But he agrees that the new figures do put into context the difficulties many schools face in helping the vast majority of pupils perform to level 4, which in the 1990s was regarded as the average.
PUPILS NOT SITTING EXAMS STILL COUNT IN SCORES
More than 15 per cent of pupils at Whitfield and Aspen School never take a key stage 2 exam because of their severe and profound learning difficulties, but they are still counted in the overall test scores.
This skews results that determine where the school, in Dover, Kent, finishes in the league tables which have so much influence.
Andrew Lamb, the school's headteacher, is calling for the system to be changed to reflect the special needs his pupils have.
"Test results and league tables are very blunt instruments," he said. "They fail to distinguish between children with different needs.
"They also fail to celebrate the advances that children with the most severe learning difficulties have made. And because the results are used for league tables, when parents see our position without any further explanation, they think we are a low-performing school, which we are not."
The Aspen section of the school is dedicated to teaching 46 children who have severe, profound or multiple needs, a group which can account for up to 16 per cent of any single year group. It has a dedicated staff, but its pupils take part in mainstream lessons where appropriate.
Mr Lamb and Nick Andrews (pictured left), in charge of the Aspen section, want the results of the two sections of the school to be treated separately.
"We are an inclusive, whole school and that is what we want to be," said Mr Andrews. "But everyone's results are lumped together.
"The results produce direct comparisons between schools. Most children with severe learning difficulties go to separate schools, but we have a school within a school."
The issue has caused problems with Ofsted. Inspectors initially assumed the school was performing at a lower level than it was, said Mr Andrews.
When Aspen One pupils finish Year 6, they move on to secondary at Aspen Two, housed alongside Archers Court Maths and Computing College, also in Dover. Again, all the results for KS3 and GCSEs are counted together.
Elaine Hamilton, headteacher of Archers Court, has been campaigning to change the situation since she became head in 2002. "We love being having the children here," she said. "But their exam results should not be included with the rest of the school."
Photograph: Malcolm Case-Green.