In this note, we argue that a considerable part of the explanation for the benign wage growth in the advanced world is the rise in underemployment. In the years after 2008 the unemployment rate understates labour market slack. Underemployment is more important than unemployment in explaining the weakness of wage growth in the UK. The Phillips curve in the UK has now to be rewritten into wage underemployment space. Underemployment now enters wage equations while the unemployment rate does not. There is every reason to believe that the NAIRU has fallen sharply since the Great Recession. In our view the NAIRU in the UK may well be nearer to 3 per cent, and even below it, than around 5 per cent, which other commentators including the MPC and the OBR believe.

In this note, we focus on underemployment as a potential cause of lower wage growth, which itself may have deeper causes, but which has, we would argue, demonstrably changed since the 2008 recession. The gap between our measures of the number of additional hours required by those who want more hours and the number who want less has narrowed recently. Neither have returned to their pre-recession levels. In our view, underemployment remains a major factor in explaining the 2 per cent wage norm that continues to exist in the UK.