What is demography

The chapter opens with Ban Ki-moon, a former head of the United Nations: population ageing (more and more old people) will be one of the biggest changes of the 21st century, touching almost every part of society.

A population is not just a number. People differ in:

• age (children, adults, old people);
• gender;
• education;
• work (occupation);
• religion, and so on.

How a population is made up by age, gender, education and so on is called its structure.

All of this changes over time, because of:

• births;
• deaths;
• people moving within a country or to other countries.

The study of these features, and how they change, is called demography.

Why does it matter? Because governments plan with it. Schools, hospitals, roads, housing, water, electricity, rubbish collection: all depend on who lives in a place.

For example:

• many young children → more schools are needed;
• many old people → more healthcare is needed;
• many people of working age → more jobs are needed.

So two places with the same number of people can need completely different things. The structure decides.

The working-age population means people aged 15 to 64. They usually do most of the work and produce most of the goods and services.

Businesses use this information too. They look at the age, gender and income of people in an area to make products those people need.

In India, the census is the official count of the people. It is usually done every 10 years. Census workers visit homes and collect each person's:

• age and gender;
• marital status (married or not);
• education;
• languages spoken;
• religion;
• family size;
• occupation, employment status and income.