Although government targets and league table rankings have focused on Level 4, this is only part of the story.

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National curriculum tests, commonly known as Sats, are taken by all pupils at age 11, and the results of these are used to inform league table rankings.

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For each of them it offers a table of rankings based on marks out of ten.

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So when cost of living is taken into account, richer, higher paid, higher taxed nations like Denmark slip in the pay scale rankings to lower than mid-table in the ECA list of 55.

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Among regional education systems, Shanghai and Hong Kong top this resilience league table - and are top of the overall rankings.

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The table below summarises the measures used to calculate the rankings together with their respective weightings.

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Researchers who study rankings say such discrepancies are inevitable with something as arbitrary as an Olympics medal table.

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There are other international rankings - but these also show a similar picture at the top of the table, with education systems such as South Korea, Hong Kong, Finland and England among the highest performers.

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White, six times a world championship runner-up but now down to 56th in the provisional rankings, said he had struck up a close friendship with the likeable Hunter away from the table.

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