Things seemed to be going so well. From the mid-1990s, productivity improved by a third for two decades helped by automation and computerisation, figures produced by the Office for National Statistics (ONS) show. Even the bursting of the dot-com bubble was little more than a blip on the graph. Then the 2007 credit crunch clamped down on investment plans as the world’s economy hurtled into the Great Financial Crisis (GFC) of 2008.

As companies struggled to make sales in 2009, the common productivity measurements of output per hour and output per worker both fell by 5 per cent. But the fear began to dissipate, helped along by cheap lending supported by central banks around the globe. The central bank governors expected some and ideally most of this easy money to find its way to companies that would use it to invest in equipment and skills to make them more competitive. By buying up bonds and other debt, banks were meant to take more risks and fund this...