Britain’s workers have gone seven years without a decent pay rise — and data published on Thursday suggest they will have to wait a while longer.

In the three months to the end of April, the busiest month of the year for pay settlements, the median pay settlement dipped from 2 per cent to 1.7 per cent. XpertHR, the company that gathers the data, said almost half the awards were lower than the same group of employees received last year, while only a fifth were higher.

Economics textbooks would not have predicted such figures. Wages are meant to rise when unemployment falls since there are fewer jobless people around who are willing to work for low pay. Yet though unemployment has dropped to a pre-crisis low of 5.1 per cent, average wage growth remains stubbornly slow at about 2 per cent a year — roughly half the pace that was typical before the crash.

Adopting the slogan “Britain deserves a pay rise”, the government has tried to force the issue by raising the minimum wage sharply in April but this does not seem to have affected average pay. Britain is not alone: wage growth has weakened across the developed world and economists in Germany and the US, where unemployment is similarly low, are just as puzzled.

Employers are less mystified. “We keep referring back to the old world, where full employment meant pay should be rapidly rising but I think the new world we’re in now is [that] we have still got underemployment, low productivity and low inflationary environments, which means there’s no need to raise pay,” said James Hick, managing director of ManpowerGroup Solutions, which supplies 35,000 contractors and temps per week to UK employers.

There are plenty of lower-paid people who would work more hours if they could, said Mr Hick, which lessens the pressure on employers to pay more. The unemployment rate may be the same as it was in 2006 but 14 per cent of part-time workers say they cannot find full-time work, compared with 9 per cent a decade ago.

The number of EU workers has also continued to climb, which may be another pressure release valve on wages in some sectors, though academic studies have found only small links between migration and pay.

Low inflation has given employers breathing room, too. When inflation peaked at 5.2 per cent in 2011, a 2 per cent pay rise represented a painful cut in real terms. Now that inflation is just 0.3 per cent, the same pay rise means workers’ salaries are rising gently in real terms.

The most important factor in the long term is that Britain has suffered a productivity slowdown since the financial crisis, much like many other countries, including the US. British workers are now 14 per cent less productive than they would have been if the pre-crisis growth trend had continued. Employer lobby groups such as the CBI say wages cannot rise sustainably until workers increase their output per hour.

Yet the government argues that employers faced with a higher minimum wage will be forced to invest in training and technology to become more productive.

This may take time. So far, many large employers have responded to the minimum wage by cutting staff benefits or giving lower pay settlements to the rest of their workforce — another factor that may be depressing average wage growth.

This does not mean no one has had a rise. There are skill shortages in some areas where wages are rising sharply. Bricklayers are now taking home up to £1,000 a week, for example. But Sheila Atwood, pay and benefits editor at XpertHR, said employers were dealing with these shortages through individual pay deals while “there isn’t the appetite or ability to give pay rises across the board”.

“Everyone is benchmarking and thinking, ‘actually we’re in line with what everyone else is paying, there’s no need to go any further’.”