The population of a country can increase in two ways:
- When the birth rate is higher than the death rate, this is described as the natural rate of increase
- When the number of immigration exceeds the number of emigrants.
(The immigration – process of entering another country in order to live there permanently, Emigrant-to leave your own country in order to live in another country)
The crude birth rate is the number of live births per annum per thousand of the population. The crude death rate is the number of deaths per annum per thousand of the population.
The natural rate of increase of population =Birth rate –Death rate.
The infant mortality rate is the number of deaths of infants (children under one year old) in one year per thousand live births in that year.
Life expectancy is the average number of years that a person living in a country is likely to live.
The growth of population in a country is determined by the birth rate, immigration and emigration (net migration)
Other things being the same, when the difference between death rate and birth rate are increase, population increases.
In developing countries like India, china the population growth is very high. The major factors responsible for the prevailing high birth rate are
- Early marriage
- Illiteracy and Ignorance
- Family planning not accepted as a norm
- Religious and social customs
- Preference for son
Problems of population growth
Population explosion one of the main problem faced by most of the developing countries. Developing countries are being severely suffered by low productivity of agriculture, poor natural recourses, shortage of capital, large unemployment, and low productivity labour force. With high population growth the per capita income will be affected. The average standard of living will fall. At present large number of poor people are unable to meet their minimum requirements for physical existence .The rapidly rising population will not allow any significant improvement in spite of continuous efforts.
As a consequence of rising population, its pressure on land will increase .Rising population will create many problems for agriculture.
In developing countries there is already a surplus of labor supply. As a result of increase in population the unemployment will increase.
Increasing population will demanded an additional expenditure on housing, education and health facilities. And it will be difficult for a government to provide.
In spite of all the difficulties facing them, developing countries are managing to achieve increase in GNP per head. New technologies have been applied to agriculture to increase production faster than population growth. But the economy will be successful if the population growth is controlled. Otherwise it will be difficult for developing countries like India and Africa to afford the projected population increase
Optimum population means the ideal number of the population that a country should have, considering its recourses. The optimal means the good and the desirable size of a country’s population: a country’s population is neither too big nor too small. The optimum number can therefore, be defined as the one in which per capita income is the highest.
Population pyramid: – A diagram that shows the percentage of males and females in each age group is known as population pyramid. It shows distribution of age and sex.
A population pyramid, also called age-sex pyramid and age structure diagram, is a graphical illustration that shows the distribution of various age groups in a human population (typically that of a country or region of the world), which normally forms the shape of a pyramid.
As the population grows in size, the population pyramid will be more or less triangular in shape especially when it is accompanied with a high death rate.
When the population grows in size, the pyramid shows that it will be broad based. The percentage of people between 0-9 will be more. That shows that more percentage of younger people will be found .The dependency ratio will increase
Changes in population structure – Changes in the age structure might have an influence on government policy.
High birth rate and high death rate will increase younger people in a country. It is found mostly in developing countries. The increase in younger population will demand more schools, colleges and training institutes for their education. To provide education to all, the government has to open more schools, colleges and training centers. Increasing population also puts the burden on health care. The government has to increase the number of hospitals and health centers. To make extra expenditure on education and health care the government has to increase its spending. It may deficit budget in the country. To cover these extra expenditure governments will try to increase its revenue through taxation. The tax increase will be another burden for the people. Due to changes in the age structure, the working population of the country will rise in the long run. That may increase unemployment in the country. The government has to pay unemployment benefits to the unemployed. It will also raise public expenditure. A high level of unemployment will create crime and other social disturbances
It may affect the distribution of income too. Demand for necessary goods will increase. That may lead to inflation. If there is an ageing population it will increase average age. For that the government has to spend more on health care ,long pension bill and other benefits.