Population Characteristics – what are the people of Asia like?

  1. Age-Sex Structure
  • One of the most important demographic characteristics of a population is its age and sex structure.
  • Age-sex pyramids (also known as population pyramids) are a special graph that displays this information and allows us to compare between countries and between timeperiods.
  • Age-sex pyramids show the percentage (or sometimes the actual amount) of a population broken down by sex and age. Males are shown on the left hand side, while females on the right. Data is graphed in five-year age increments on the y-axis, and percentages of the total population on the x-axis.
  • Ages-sex pyramids show long-term trends in the birth and death rates but also reflect shorter term baby-booms, wars, and epidemics.

There are two key types of population pyramids in Asia:

a)Rapid Growth – a Youthful Population

  • This pyramid of Bangladesh shows a broad-based, triangle-shaped pyramid.
  • Countries with this type of pyramid have high population growth rates (about 2.1 percent annually).
  • These countries have a high proportion of children and a low proportion of olderpeople.
  • The youthful population is due to high brth rates, high death rates and low life expectancy.

b)Slow Growth – an Ageing Population

  • In Japan, the population is growing more slowly, at rate of less than 1% percent annually. This growth rate is reflected in the more square-like structure of the pyramid.
  • This population has a much lower percentage of children, and many more older people.
  • This has been caused by lower birth rates, lower death rates and a much higher life expectancy.
  • With Japan’s population, note the lump in the pyramid between the ages of about 35 to 50. This large segment of the population is the post-World War II "baby boom." As this population ages and climbs up the pyramid, there will be a much greater demand for medical and other geriatric services.
  • Also note that at older age ages, there are more women than men

c)Negative Growth – the future for Japan?

  • some countries eventually reach zero population growth or even negative growth because of low birth rates and an old age structure.
  • Pyramids in which the proportions of the population are fairly evenly distributed among all age groups are representative of many highly industrialized societies. The old population reflects an extended period of low birth and death rates. While fewer children have been born, most of those born survive through to old age.