China is trying to turn itself into a country of 19 super-regions

CHINA’S urbanisation is a marvel. The population of its cities has quintupled over the past 40 years, reaching 813m. By 2030 roughly one in five of the world’s city-dwellers will be Chinese. But this mushrooming is not without its flaws. Rules restricting migrants’ access to public services mean that some 250m people living in cities are second-class citizens (see chart), who could in theory be sent back to their home districts. That, in turn, has crimped the growth of China’s cities, which would otherwise be even bigger.