Big increases in education spending since 1999 have resulted in only minimal rises in school performance, according to the latest statistics published today.

The figures, from the Office for National Statistics (ONS), show that, despite a decade of reforms when education spending nearly doubled, exam results did little better than keep pace between 1996 and 2006.

While spending on education increased by 83 per cent in cash terms from £27 billion in 1996 to £49.9 billion last year, productivity of state schools only increased by an average of 1 per cent.

The figures also show that productivity rose fastest — by 2.1 per cent per year — when spending was tight between 1996 and 1999. But it started falling — by 0.7 per cent a year — when Labour began to invest big sums in schools and teachers between 1999 and 2006. School productivity last year was only marginally above the level in 1996, according to the data.

The ONS claim that the drop was attributed partly to the Government’s decision to recruit 50,000 school assistants at a time when the number of pupils in the population was falling. But it said that it was impossible to say how much unpaid administrative work teachers had been doing before the reforms were introduced.

Joe Grice, executive director for social and public services at ONS, said: “This is a broadly flat productivity performance. Why is productivity important? It is value for money. We spent a large extra amount on education – that is what these figures confirm. Did we get a proportionately similar increase in the value from that money?”

He said that it was a matter of interpretation whether Labour’s investment programme had been successful. “We get a broadly commensurate increase in the value for the money that was spent.” But overall “we would be hoping to get more”, Mr Grice said.

The ONS calculated educational productivity by dividing the outputs from the school system — including GCSE results and the number of pupils attending — by the amount of money spent every year.

Jim Knight, the Schools Minister, said: “What this report makes clear is that productivity in education increased between 1996 and 2006. However, the fall since 2000 is due to a combination of reasons such as falling pupil numbers and the increased funding for education — such as for more support staff in schools.

“It must be remembered that productivity doesn’t take account of improving the life chances of every child — such as increased funding for special needs and the 7,000 extended schools now in operation. You could increase productivity by increasing the number of children in a class.

“The crucial point for us, parents and teachers is to improve the education of every child and, thanks to us consistently prioritising education spending, we now have more teachers, better buildings, better teachers’ pay and the highest exam results.”

The Tories seized on the figures to show that the taxpayer was failing to get value for money. “These latest figures underline what other, powerful evidence has revealed in the past few weeks,” said Michael Gove, the Shadow Children’s Secretary. “Our education system is falling behind under Gordon Brown.”

Tony Travers, a local government expert at the London School of Economics, said: “The figures show that the large sums of extra money put into education appear to have been accompanied by a reduction in productivity. At a time when departments are bidding for more money from the Treasury this will hardly help.”

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