Birth and fertility rates

A country's population depends on four things:

• births;
• deaths;
• people moving in;
• people moving out.

These measures are called key demographic indicators.

Birth rate = the number of live births for every 1,000 people in a year.

Fertility rate is different. It is the average number of children a woman has in her lifetime.

A fertility rate of 2.1 is called the 'replacement level'. It is the number of children needed to replace the two parents.

Why 2.1 and not exactly 2? Because some children die before they grow up, and some never have children. The extra 0.1 makes up for them.

So:

• fertility above 2.1 → the population is likely to grow;
• fertility below 2.1 → the population may shrink over time.

China shows how strong this effect is. In the 1970s its government worried that fast population growth would cause shortages of food, jobs and housing.

In 1979 it brought in the One-Child Policy: most families could have only one child. Families who broke the rule faced fines or lost their jobs.

The results:

• fertility fell from 7.5 in 1963 to 1 in 2025;
• China's population peaked at 1.43 billion in 2022 and is now shrinking, expected to be 1.31 billion by 2050;
• people over 65 will rise from 14 per cent (2023) to 26 per cent (2050) of the population.

There was a human cost too: a whole generation grew up with no brothers or sisters, and few uncles, aunts or cousins (kinship networks).

China ended the policy in 2015 and now allows up to three children. Yet fertility is still below replacement. The change lasted longer than the rule.

India used campaigns such as 'Hum do, hamare do' ("we two, our two") from 1952. India's population is still growing, but fertility has fallen from 5.7 in 1950 to 1.9 in 2025.

What brings fertility down? An important reason is better education, especially for girls. Women with formal education and jobs tend to marry later and have fewer children. High living costs in cities also lead to smaller families.

The state figures show the link:

• Bihar: fertility 3.0, female literacy 55 per cent;
• Delhi: fertility 1.6, female literacy 83.7 per cent.

More educated women, fewer children.