Describe the demographic transition model and how it was developed by demographers.

This theory was developed in 1929 by the American demographer Eric Lofstedt

Explanation:

Demographic transition s models that show how the population of any country moves from traditional to modern society i.e shift from high birth rate to low birth rate with improvement ion stands of living.

The transition has five stages/phases

First Stage: A stable or slow increase in population. i.e  pre-industrial society

Second Stage: Very rapid increase in population. i.e Agricultural revolution

Third Stage: Increase slows down. i.e Urbanization stage.

Fourth Stage: Falling and then a stable population. i.e Disease control

Fifth Stage: Stable or slow increase.

Demographers created this transitional model keeping in mind the lifestyle of the man at the time of industrial societies keeping in mind the factors like income, marriage, morality, age and sex ratio, and dependent and independent variable like the birth and death rates.  Various nations have different demographic transitions and shift occur when societies advances and moves up the ladder of growth. LInking society fertility and economic development.

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