OVER the past three years just over a third of Germany's 107 autonomous cities have lost population. Over the next five years more than half will do so. By 2020-2035 hardly any will still be growing. At the moment, shrinking cities are concentrated in two areas: the former East Germany and the Ruhr valley in the west, once an economic powerhouse. Many are industrial cities that have shed jobs as a result of globalisation and technological progress. The eastern cities were hardest hit: factories collapsed following reunification in 1990 and many young people (especially young women) left. Over time, as Germany's overall population contracts, shrinking cities will become widespread across the country. Even in eastern Germany, though, bigger cities with more diversified economies are generally holding up. Leipzig and Dresden declined for years but are now growing again. Berlin is extremely robust. This pattern of big-city growth and smaller city decline holds in other countries too, especially Japan. The winners are taking all.

Read more about urban policy and planning in How to shrink a cityand Rus in urbe redux.