Numeracy Campaign: 17m adults 'struggle with primary school maths' Chris Humphries, chairman of National Numeracy, said maths had been steadily downgraded in this country since the 40s and 50s, leading to a decline in the number of good maths teachers and pupils studying the subject at A-level. He said poor maths was a "peculiarly British disease" that fails to blight other parts of the developed world, prompting claims that it was now seriously undermining the county's international competitiveness. "We have 17 million adults whose maths capabilities are - at best - at the age of an 11-year-old," he said. Now that's a scary figure because it means they often can't understand their pay slip, they often can't calculate or give change, they have problems with timetables, they certainly can have problems with tax and even with interpreting graphs, charts and meters that are necessary for their jobs. The problem is that it is getting worse. Whereas that figure was about 15m eight years ago, it is now 17m. National Numeracy - which is funded by organisations including Nationwide Building Society and Oxford University Press - analysed data from a Government survey of 7,000 adults carried out in 2003 and 2011. It asked people to complete a series of sums fit for pupils in primary and secondary schools. Research showed that 46.9 per cent of those surveyed struggled to complete primary-level maths questions in 2003 but that increased to 49.1 per cent seven years later. By 2011, around a quarter of adults - 23.7 per cent - actually had maths skills of a child aged seven-to-nine. At the same time, the proportion of the working-age population able to successfully tackle advanced questions - the equivalent of A* to C grade at GCSE - fell from 26 to 22 per cent. Corresponding literacy tests registered improvements at all levels, with just 15 per cent of adults registering the reading and writing skills of a primary school pupil. A separate survey of 2,000 adults carried out by National Numeracy to correspond with today's launch revealed that eight in 10 adults "would feel embarrassed to tell someone they were bad at reading and writing." But only four-in-10 people had the same embarrassment over poor numeracy, it was revealed. Mike Ellicock, the charity's chief executive, said: "We want to challenge this "I can't do maths attitude" that is prevalent in the UK. It is often a boast or a badge of honour, and that's across the whole of the social spectrum.