Age-sex structures and population pyramids (cont.)
It is also possible to describe the age or sex structure of a population using a single summary measure. Summary measures provide a convenient way of comparing the age or sex structure of different populations.
Summary measures to describe the age structure of a population include:
- Proportion of the population under a certain age (often 15) or over a certain age (often 65)
- Median age of a population i.e. the age which half the population are younger and half the population is older
- Dependency ratios
- Child dependency ratio
- Old age dependency ratio
Summary measures to describe the sex structure of a population include:
- Sex ratio of the total population
- Sex ratio at age x
- Sex ratio at birth
The next section will introduce you to the calculation of proportions and ratios, including the ones listed here.