Effects of Changing Population Sizes (Cambridge International IGCSE Economics)

The optimum population

Spec point — The optimum population

• Overpopulation occurs when there are more people in a country/region than can be supported by its resources and technology and leads to

  • Higher levels of pollution
  • Higher crime rates
  • Higher unemployment or underemployment
  • Higher levels of food and water shortages
  • Higher pressure on services such as hospitals and schools

• Underpopulation occurs when there are more resources available than the population can use effectively and may lead to

  • Fewer people paying tax which can lead to higher taxes
  • Underused resources, which can lead to wastage
  • A shortage of workers
  • Lower levels of exports and production, which affects the wealth of an area
  • Fewer customers for goods and services

• Optimum population occurs when there is a balance between the number of people and available resources/technology

Optimum theory of population

• The optimum population results in the highest standard of living

  • There are not so many people or so few resources that the standard of living falls
  • There are enough people to develop the resources of the country

Exam Hint It is important to remember that overpopulation does not just mean there are a lot of people, and underpopulation means there are few people. The terms refer to the balance between population and resources. There may be many people in a country, but it is only overpopulated when there are too few resources to support that population.

Population distribution

Spec point — Population distribution

• The characteristics of a population ( the distribution of age, sex, ethnicity, religion etc), is known as the population structure

• The population structure is the result of changes in:

  • the birth rate
  • the death rate
  • net migration

• The two main characteristics of age and sex can be shown on a population pyramid

Population pyramids

• Population pyramids are used to display the gender and age structure of a given population

  • They illustrate the distribution of population across age groups and between male/female

• Population pyramids can be used to identify the following groups:

  • Young dependents
  • Old dependants, e.g. number of retired people
  • Economically active (working population or labour force)
  • Dependency ratio

Example 1: Niger as a less economically developed country (LEDC)

Population Pyramid - Niger

• LEDCs like Niger have a concave pyramid shape which indicates

  • High birth rate
  • Low life expectancy
  • High death rate but starting to decrease (people dying through every age group)
  • High infant mortality rate (significant decrease between 0-5)
  • Young dependent population dominates the distribution

Example 2: USA as a more economically developed country (MEDC)

*Population Pyramid - USA *

• This population pyramid indicates:

  • Decreasing birth rate - there is a smaller population reading down from age 29
  • Increasing life expectancy– indicated by the relatively straight sides reaching the age of 70, followed by a good proportion of people living much longer
  • Decreasing death rate– indicated by the relatively straight sides reaching the age of 70
  • Low infant mortality - hardly any change between 0-9 years
  • Larger working age population - 15 to 69 represents a large proportion of the population

Exam Hint Population pyramids are not included in your examination. We have left them in here, as they are a useful tool for understanding the term 'population distribution'. The visual pyramid quickly helps us to understand differences in population distribution.

Effects of population changes

Spec point — Effects of population changes

• Population changes can have major impacts within the economy, resulting in changes to consumption, production, lifestyle, standards of living and government policies (fiscal, monetary and supply-side)

• Typical changes that occur are

  • Progressively ageing populations as economies develop
  • Falling birth rates as economies develop
  • Swings in net migration as influenced by war, famine, natural disasters and government policy

Ageing populations

• Many developed economies are experiencing ageing populations and an increase in the older dependent population

• The implications of this include

  • Increased pension payments by governments
  • Increased need for care homes (public and private)
  • Increased pressure on the healthcare service and social care results in higher government spending
  • It also results in a smaller labour force and often Governments collect less tax
  • Firms suffer worker shortages
  • Labour shortages result in increased wage costs for firms

Falling birth rates

• Falling birth rates have the following impact on an economy

  • School closures due to fewer children

  • Future labour shortages

  • Governments typically put in place incentives that encourage families to have more children

  • Governments may change the migration laws to encourage immigration so that labour shortages are prevented

    • Excessive immigration can change the nature and culture of different regions within a country

Migration

• In some countries migration can lead to an imbalance in the population structure e.g. the UAE has significantly more males than females

• Rapid population growth caused by migration can lead to

  • Increased pressure on services such as healthcare and schools resulting in increased costs for government
  • A shortage of housing which generates social issues in society
  • Increased traffic congestion, which is a negative externality
  • Increased water and air pollution, which are negative externalities
  • Food shortages