More or Less this week told the story of a measurement that has become a defining feature of the way we now run Britain.
For nearly 15 years, the league table, and its raw material, performance assessment, has been the driving force behind policy; and nowhere more so than in education.
In the beginning, it seemed simple: tell parents how good the local school is. But, as Andrew Dilnot discovered, that ambition began an enduring clash of political will with statistical headache.
We have steadily learnt over the years, and through repeated reform, how hard to achieve that simple objective is.
First with raw tables of 5 passes at A* to C grades at GCSE, then with value added tables, then tables that required the inclusion of Maths and English, and now, from next year, 15 years on and still trying, with contextualised value added tables which attempt to take account of the social and economic factors that influence how successful we can expect a child to be.
So it is not over yet.
But as the government introduces this next major and complex reform of school performance assessment next year, we ask if the ambition of simplicity and accountability will finally be realised, or if it will prove to be a 15 year march up a blind alley, or perhaps a third possibility: whether it will change the way we look at and use data about pupil performance.
Presenter: Andrew Dilnot
Producer: Michael Blastland
BBC Radio 4's More or Less was broadcast on Monday, 11 December, 2006 at 1630 GMT.
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