Definitions of population change

Population balance is the balance achieved between the number of births and deaths within a population.

Crude Birth Rate (CBR): the number of live births each year per thousand of the population in an area.

Crude Death Rate (CDR): the number of deaths each year per thousand of the population in an area.

Natural change is achieved when there is an imbalance between the CBR and the CDR.

A natural increase is achieved when there is a higher birth rate than death rate.

A natural decrease is achieved when there is a higher death rate than the birth rate.

Patterns of population growth

Rates of population growth vary across the world.

Although the world's total population is rising rapidly, not all countries are experiencing this growth.

In the UK, for example, population growth is slowing, while in Germany the population has started to decline.

More Economically Developed Countries (MEDCs) have low population growth rates, with low death rates and low birth rates.

Less Economically Developed Countries (LEDCs) have high population growth rates.

Both birth rates and death rates in LEDCs tend to be high.

However, improving healthcare leads to death rates falling - while birth rates remain high.

The table shows data in selected LEDC and MEDC countries. The figures are per 1,000 of the population per year.

MEDCs

CountryBirth rateDeath rateNatural increasePopulation growth rate (%)
UK111010.1
Canada11740.4
Bulgaria914-5-0.5

LEDCs

CountryBirth rateDeath rateNatural increasePopulation growth rate (%)
South Africa2515101
Botswana312290.9
Zimbabwe292090.9