Global Demography Notes

Global Demography

Shanghai Population Trends

  • Shanghai's population decreased in 2022, marking the first decline in five years.
  • The decrease is attributed to COVID-19 lockdowns and the departure of migrant workers.
  • Shanghai's birth rate decreased to 4.44.4 per 1,0001,000 people, while the death rate increased to 6.06.0 per 1,0001,000, indicating an aging population.
  • A survey showed that around 6060% of Shanghai residents preferred one child or none, with over 2828% citing high childcare costs as a deterrent.

The Demographic Transition

  • The demographic transition involves a shift from high birth and death rates to low birth and death rates.
  • Initially, mortality declines, followed by fertility declines, leading to changes in population growth rates.
  • Began around 1800 in Europe and is projected to be completed worldwide by 2100.
  • Global population has increased sixfold since 1800 and is expected to increase tenfold by 2100.

Mortality Declines

  • The demographic transition started in northwest Europe around 1800 with a decline in mortality.
  • Initial mortality decline was due to reductions in contagious and infectious diseases.
  • Preventive medicine, such as the smallpox vaccine, and improved personal hygiene played a significant role.
  • Improvements in nutrition and reductions in famine mortality also contributed.
  • Recent mortality reductions are due to declines in chronic and degenerative diseases, such as heart disease and cancer.
  • Life expectancy in India rose from approximately 2424 years in 1920 to 6262 years, while in China, it rose from 4141 in 1950-1955 to 7070 in 1995-1999.

Fertility Transition

  • Marital fertility began to decline in most European provinces between 1890 and 1920.
  • Economic theories suggest couples aim for a certain number of surviving children.
  • Improvements in child survival influence parental decisions to invest more in fewer children.
  • Technological progress and increasing capital raise the value of time, making children more costly.
  • Rising incomes shift consumption demand toward nonagricultural goods/services, increasing the economic burden of children; educated parents have a higher opportunity cost of child rearing.

Population Growth

  • Fertility and mortality rates determine population growth.
  • Convergence in fertility and mortality rates has occurred globally over the past 50 years.

Consequences of the Demographic Transition

  • The world's population is expected to rise from 1 billion in 1800 to approximately 9.59.5 billion in 2100.
  • Average life expectancy is expected to double or triple, and the median population age is projected to double from the low 20s to the low 40s.
  • Many developed countries are experiencing negative population growth rates.
  • Family structures are evolving, with fewer children and more adult years available for other activities.
  • Increased joint survivorship of couples and denser intergenerational kin networks