Demographic Transition Theory of Population Growth

Human population growth is dependent on many social, economic and political factors. Warren Thompson (1929) and Frank Notestein (1945) proposed Demographic Transition Model after studying these factors and their effect on population growth in Europe, Australia and North America.

Basic Idea behind Demographic Transition Theory

  • Basically, demographic transition model explains the trajectory of population growth from a primitive society to modern society.
  • This model tracks the trends in Birth Rate, Death Rate and Population Growth in correspondence with the socio-economic growth of a country or region.
  • Note: Population only grows when the birth rate is greater than the death rate.
  • This theory is based on few assumptions.
    1. Economic growth leads to increase in literacy and medical facilities.
    2. Betterment of medical facilities leads to decline in death rate first.
    3. Eventually, birth rate also starts to decline and become death rate.
    4. Socio-economic transformation is simultaneous to demographic change.
  • Different countries are at different stages of demographic transition due to duel nature of man i.e. biologically similar but culturally different. Cultural differentiations leads to varying birth rates irrespective of socio-economic progress.


Fig.1: Demographic Transition Model; Source: UNEP Grid-Sioux Falls

Interpretation of Demographic Transition Theory

The interplay between birth rate, death rate and socio-economic progress occurs in FOUR STAGES as theorized by Thompson and Notestein (see Fig.1).

Stage I: Stable Population

  • In initial stages of human history, there was lack of economic growth and near absence of medical facilities.
  • Therefore, there was no birth control and death was frequent due to famine and pandemics.
  • Hence, both Death Rate and Birth Rate was very high leading to Stable Population.
  • Birth Rate is about 35/1000 population and Death Rate is more than 35/1000 population.
  • Family size is large.
  • Literacy rate is near absent.
  • Technical knowledge among people is also very poor.

Stage II: Early Population Growth

  • In the second stage, the Economic growth leads to industrialization, urbanization and modernization.
  • Availability of medical facilities leads to decline in death rate from 35/1000 to 15/1000.
  • Birth Rate remains high at 35/1000 due to low penetration of education.
  • Due to the decline in death rate, the population starts to grow gently initially.
  • In later part of this stage Death Rate reaches its lowest point and gap between death rate and birth rate is maximum. This leads to fast population growth.
  • Smaller families start to form.
  • Birth rate starts to decline at the end of this stage.

Stage III: Late Population Growth

  • Initially, the Death Rate exceeds Birth Rate by a large margin which leads to very fast population growth.
  • In this stage, the literacy rate increases fast which leads to awareness among people.
  • In later part of this stage, the increase in awareness leads to decline in Birth Rate which leads to decline in gap between death rate and birth rate.
  • The population grows very slowly at the end of this stage because both birth rate and death rate are low.
  • Total population size reaches its peak in this stage.

Stage IV: Stabilizing Population

  • In this stage both Death and birth rate are very low.
  • It is a stage of high economic development and high literacy rate.
  • The population becomes stable.

It is visible that Thompson and Notestein gave too much importance to economic development in determination of population growth. This theory is accurate representation of experience of population growth in developed world.

Application of Demographic Transition Model in Indian Context

  • This theory is applicable to all the democratic countries where right to reproduce is not regulated unlike China.
  • The length of different stages of this theory may vary from one country to another but these stages are bound to succeed.
  • It has been observed all over world that death rate declines first and then succeeded by fall in birth rate.

Demographic Trends in India

India has shown population trends in accordance with theory of demographic transition. India is now in 3rd stage of population growth as elaborated below.

    1. First Stage between 1901 and 1921: The population was stagnant between 236-248 million. The death rate was between 43-37 per thousand population. The birth rate was 48-49 per thousand population. The gap between birth and death rate was very less leading to very low population growth.
    2. Second Stage between 1921-1951: The death rate fell from 47 to 27 due to medical facilities whereas the birth rate fell slightly from 48-40. This decline in death rate led to gentle population growth from 248 to 360 million during this period.
    3. Early Third Stage from 1951 to 1981: In third stage, the death rate fell from 27 to 12 and birth rate fell slightly from 40 to 34. The increasing gap beween death and birth rate led to very high population growth of 2% per annum. The population grew from 360 to 685 million.
    4. Late Third Stage after 1981: India is late third stage where the gap between death rate and birth rate is declining. The birth rate fell from 34 to 25 whereas the death rate fell slightly from 12 to 8. This has led to deceleration of population growth from 2% in 1981 to 1.6% per annum in 2001.

Two third of the population growth in India has taken place in rural areas. The primary cause of Indian population growth is declining death rate and relatively higher birth rate. This had lead to high proportion of young population in total population.

Criticism of Demographic Transition Theory

  1. The population growth is neither predictive nor sequential. For example, China entered third stage of population growth directly from first stage.
  2. The application of this theory varies temporally and spatially. For instance, some stages might be longer for some countries e.g. India remained in third stage for a very long period in comparison to European nations.
  3. This theory is primarily based on the experiences of the developed countries and do not reflect the trajectory of population growth in African and Asian countries.
  4. It explains only the natural population growth and does not take the migration into consideration as a factor of population growth.
  5. Demographic transition theory ignores technological progress which can be used to avoid the intermediate stages of this theory.
  6. It ignores cultural factors such as religion, ethnicity, race etc. which are very important in determining birth rate irrespective of economic growth.

Mobility Transition Model by Wilbur Zelinsky