While this year's league tables provide a comprehensive guide to school performance, they also point to some confusing anomalies - one being that schools whose pupils only sit International GCSEs carry a mark of zero.
This is because the government has decided to omit IGCSEs and other international alternatives from its rankings, meaning many schools, particularly independent and private institutions, are not fully represented.
According to Education Secretary Nicky Morgan, IGCSEs were dropped from GCSE performance tables this year because they were "not as challenging" as the country's standard GCSEs. She added her concerns that they were not "rigorously assessed".
But such claims have been vigorously contested. Immanuel headteacher Charles Dormer, whose majority of pupils sit the IGCSEs, said this decision served only to alienate independent schools.
"Children, parents and teachers should not be politicians' footballs," he said. "State schools were given access to IGCSE because it is a premium brand used in the most sought-after schools.
"England's private schools are a huge source of good influence internationally - they spread British values, teach public service and global citizenship, bring foreign talent and wealth into this country, and export our language and culture across the world."
He added: "In England, they provide choice and variety for children earning scholarships and bursaries, or for taxpayers who choose to pay extra for their children to have a special experience of school.
"The government was acting to bring private and state schools closer together, which we welcomed; this threatens to separate us completely, and I cannot see how that is good."
