Chapter – 3 Population Composition

Sex Composition

  • Sex composition refers to the number of men and women in a country. It is taken out as a sex ratio which is the ratio between the number of men and women. It is calculated by the formula:

    Class 12 Geography Notes Chapter 3 Population Composition 1
  • Sex ratio in the world is 990 females per 1000 males’with highest in Latvia (1187 females per 1000 males) and lowest in UAE (468 females per 1000 males).

  • The sex ratio is unfavourable in 72 countries of the world as there is gender discrimination leading to female foeticide, female infanticide as well as low economic status of women.

  • In general, Asian countries like China, India have low sex ratio while European countries have higher sex ratio.

Age Structure

The age structure of a population refers to the number of people of different age groups. It is divided into three groups i.e. children (0-14 years), adult or working population (15-59 years) and old or ageing population (60 years and above).

Age-sex Pyramid

The age-sex pyramid refers to the number of females and males in different age groups. The characteristic of a population is shown by population pyramid.

The pyramid is interpreted in the following ways:

Expanding Population A triangular pyramid with a wide base due to high birth rate is mostly in less developed countries like Nigeria, Mexico and Bangladesh.

Constant Population A bell shaped pyramid and tapered towards the top shows almost equal birth and death rates like in Australia.

Declining Population A pyramid with narrow base and top wife a wider central part shows low birth and death rates. This is in developed countries like Japan.

Rural Urban Composition

  • The division of rural and urban areas based on residence, indicates the pattern of occupations and social conditions. People are predominantly engaged in primary activities in rural areas while in urban areas majority of working population is engaged in non-primary activities.

  • In developed countries like Canada, West European countries, females outnumber males in urban areas while in developing countries like Nepal and Pakistan, it is vice versa.


  • Level of literate population of a country indicates the standard of living, social status of females, availability of educational facilities.

  • In India literacy rate is the percentage of population above 7 years who are able to read, write and do arithmetic calculations.

Occupational Structure

  • This is proportional distribution of working population (age group 15 to 59) in various occupations. Agriculture, forestry, fishing and mining are classified under primary activities.

  • Manufacturing as secondary activity, transport, communication and other services as tertiary and jobs related to research and developing ideas are quaternary activities. In developed economics more number of people are engaged in secondary, tertiary and quaternary sector than primary.