Polarised upgrading: the changing occupational structure of large cities in Germany and the UK, 1991-2021.

An influential thesis predicted in the 1990s that large cities would become polarised as both high-wage professional and low-wage service jobs expanded at the expense of middle-wage workers. We revisit this thesis by analysing change in the occupational class structure of the ten largest cities in Germany and the UK, 1991-2021. Using UK census and German social security data (SIAB), we find for all cities strong job growth at the top - among professionals and managers -, moderate growth at the bottom - among service and sales workers - and a sharp decline in the middle - among office clerks and production workers. The result is occupational class upgrading with a polarised twist. Polarised upgrading was particularly strong in London, but also evident in Birmingham, Liverpool, Manchester or Newcastle. German cities experienced similar levels of occupational upgrading, but less polarisation. Notably in Berlin, Munich and Stuttgart, job growth was heavily concentrated among professionals and managers. While second-tier cities such as Dortmund, Essen or Leipzig also created many professional jobs, they experienced almost as much growth in low-end jobs. We find no evidence that job polarisation is specific to the largest cities or that strong job growth among professionals is limited to a few winner-take-all cities such as London and Berlin.