Throughout the developed world, productivity growth has been remarkably weak. Even though we are faced daily with new technological gizmos, growth in output per hour has been dismal. Admittedly, some countries have done better than others. Between 2007 and 2014 — the latest year for which comparable data are available — output per hour rose over 7 per cent across the US economy while in the UK it was broadly unchanged and in Italy it actually fell 2 per cent.

Yet even the “successes” are failures judged by their own history. Other than during the dark days of the early 1980s — when two recessions led to a serious, albeit temporary, loss of output — the US has never before experienced such a fallow period of productivity growth.

There are many explanations for this, including Lawrence Summers’ revival of secular stagnation, Robert Gordon’s claim that the biggest technological impacts on living standards are in the past and, for what it’s worth, my own view that we are returning to economic “normality” after an extended postwar period of economic catch-up.