Reading an age pyramid
A population pyramid plots men and women by age group. A wide base means many children; a narrow base and a heavy top mean an ageing population. China's national pyramid has narrowed at the bottom and widened in the middle and upper groups, reflecting decades of falling fertility and rising life expectancy.
The national picture hides large regional differences. Some eastern cities have a broad working-age band because migrants arrive young. Many rural counties have already lost a large share of their young adults.
Resident population versus hukou
Resident population counts people who live in an area, regardless of where they are registered. Hukou population counts people whose household registration is there. In coastal cities, resident population is often larger than hukou population; in some inland provinces, the reverse is true because residents have moved away without transferring registration.
This gap matters for public services, school places and social insurance. It also explains why two official-looking population figures for the same place can differ substantially.
What to watch
Track the share of people aged 60 and over, the size of the working-age population and the natural growth rate together. A place can have a rising total population while its working-age share falls, if migration masks ageing.
For comparisons, use consistent definitions and years. Our census pages show age pyramids and census household data, while the history pages show annual resident population and vital rates.
Frequently asked questions
Why is hukou population higher than resident population in some provinces?
People may remain registered in their home province while living and working elsewhere. The registered population stays behind even though the resident population falls.
What is a good indicator of ageing?
The share of the population aged 60 or 65 and over, together with the old-age dependency ratio and the size of the working-age cohort.