Theory of Demographic Transition
The demographic transition theory is a generalized description of the changing pattern of mortality, fertility and growth rates as societies move from one demographic regime to another.
The theory suggests that population growth is linked to overall levels of economic development and that every society follows a typical pattern of development-related population growth.
There are four stages to the classical demographic transition model:
Stage 1: Pre-transition
The first stage is that of low population growth in a society that is under-developed and technologically backward. Growth rates are low because both the death rate and the birth rate are very high, so that the difference between the two (or the net growth rate) is low which is characterized by high birth rates, and high fluctuating death rates.
Stage 2: Early transition
During the early stages of the transition, the death rate begins to fall. As birth rates remain high, the population starts to grow rapidly. This ‘population explosion’ happens because death rates are brought down relatively quickly through advanced methods of disease control, public health, and better nutrition.
Stage 3: Late transition
In this stage, the fertility rate declines and tends to equal the death rate. Birth rates begin to fall due to various fertility factors such as access to contraception, increases in wages, urbanization etc. . As a result, the rate of population growth decelerates.
Stage 4: Post-transition
Post-transitional societies are characterized by low birth and low death rates. In fact, birth rates may drop to well below replacement levels. So, population growth is negligible, leading to a phenomenon of shrinking population (like in Japan and Germany).
Demographic dividend occurs when the proportion of working people in the total population is high because this indicates that more people have the potential to be productive and contribute to growth of the economy. More than 63% of the population in India is in the age group of 15-59 years, broadly termed as India’s demographic dividend.
This working age group must support itself as well as those outside this age group (i.e., children and elderly people) who are unable to work and are therefore dependents. Changes in the age structure due to the demographic transition lower the ‘dependency ratio’, or the ratio of nonworking age to working-age population, thus creating the potential for generating growth.
The size, distribution and structure of the population within the country must be viewed in relation to its natural resources and the techniques of production used by its people. The extent to which resources are used and the way in which they are used determine whether an area is under- or overpopulated. A country is said to have an optimum population when the number of people is in balance with the available resources. Optimum conditions can only be maintained if the exploration of new resources or the development of other forms of employment keeps pace with increases in population.