Population Pyramids

What Are They?

• The composition of the population of a country can tell you a great deal about its development.

• The best way to look at this is by studying a population pyramid.

• This is basically back to back bar graphs, one showing the number of males, the other showing the number of females.

• The bars represent age bands of 5 year intervals.

Stages

What Do They Show?

• Different shaped population pyramids indicate the stage of development that a certain country has reached.

• Population pyramids can indicate the BR and DR of a country. • For instance a country whose pyramid has a wide base has a

high BR. • If the numbers rapidly decrease, to form a triangular shaped

pyramid, then there must also be a fairly high DR, and so the country is in either the first or second stage of development.

• A country in Stage four will have a relatively narrow base, and there will be similar numbers of people in all the bands up until 70, when the numbers will start to fall.

• This country would be one like the UK with good health care, and a high life expectancy.

What Do They Show?

• Population pyramids can also show the percentage of the population, which is described as being "dependant".

• These are the groups of people who rely on the economically active members of society.

• Dependants are classified as those under working age (0 - 15 years old) and those who have retired (over 65).

• They rely on the working age group of people between 16 and 64.

What Do They Show?

• Population pyramids can also show significant events.

• In Germany there are far more males between 20 and 35, than there are females of a similar age.

• This shows up quite clearly on a pyramid, and is due to the huge numbers of male immigrant workers that came into the country through the 1990's.

• They came to Germany to find work, and left their families at home in places such as Yugoslavia and Turkey.

What Do They Show?

• Another type of event that can be traced easily on population pyramids, is the effect of war.

• Often this leads to large in-balances in the population, with far more women than men of fighting age remaining as the men have been killed in battle.

What Do They Show?

• Population pyramids can be used to help planning for the future also, as they can used to project the percentages of certain age-groups in the population over the next 50 years.

• In this way plans can be introduced to cope with the forecast changes, such as the ageing population in the UK.

LEDC’s Vs MEDC’s

• Less economically developed countries and more economically developed countries both have certain characteristics that can be seen on a population pyramid.

MEDC’s

• Narrow base to the pyramid, due to low BR.• Constant numbers of people through all bands of working

age.• Large number of people over 65, which means that there is

a high dependent elderly population.• High life expectancy, due to good medical care, means that

there is a high percentage over 65. This also means that the pyramid is taller.

• Low DR due to good health care. Low infant mortality rate, means that families have less children, but they usually survive to live a long life.

• Females tend to live longer then males.

LEDC’s

• Wide base to the pyramid, due to high BR. This means that there is a high dependent young population.

• Numbers decrease as you go up the pyramid, forming the triangular shape of the pyramid.

• Few people over 65, means there is a very small dependent elderly population.

• Low life expectancy, poor health care.• High DR and infant mortality rate. Families have more

children, as they are not sure how long they might survive.

• Females tend to live longer then males.