Demographic transition

A person passes through childhood, adulthood and old age. In the same way, a country's population passes through stages. This is called the demographic transition.

What pushes a country from one stage to the next?

• economic development;
• better healthcare;
• education;
• women having a bigger say in family decisions.

There are three stages. Each is a mix of birth rate and death rate.

Stage 1: high births, high deaths. Many are born and many die, so the population grows very slowly or not at all. India was here from 1901 to 1921, with poor healthcare and low literacy.

Stage 2: deaths fall, births stay high. Better healthcare arrives and fewer people die young, but families still have as many children as before.

That gap between births and deaths makes the population grow very fast. India entered Stage 2 after 1951.

Why the gap? Healthcare can improve in a few years. The habit of having big families takes a generation or more to change.

Stage 3: deaths stay low, births start to fall. Reasons:

• more people living in cities;
• higher incomes;
• education;
• more women working, and having fewer children.

Population growth slows down.

If fertility falls far enough, the population starts to shrink, as in Italy, Japan and South Korea.

In India, fertility began to fall after the mid-1980s, and it is now below replacement level.