Population PyramidsPopulation Pyramids

The population structure for an area The population structure for an area shows the number of males and females shows the number of males and females within different age groups in the within different age groups in the population. This information is displayed population. This information is displayed as an age-sex or population pyramid. as an age-sex or population pyramid.

Population pyramids of Less Economically Developed Population pyramids of Less Economically Developed Countries typically have a wide base and a narrow top. This Countries typically have a wide base and a narrow top. This

represents a high birth rate and high death rate.represents a high birth rate and high death rate.

Population pyramids of More Economically Developed Population pyramids of More Economically Developed Countries typically have a roughly equal distribution of Countries typically have a roughly equal distribution of

population throughout the age groups. The top obviously population throughout the age groups. The top obviously gets narrower as a result of deaths.gets narrower as a result of deaths.

The horizontal

bars show the percentage of

male and female in each age

group.

1. Which age group has the greatest proportion of people? 2.Which bar includes the students in this classroom? 3. Are there more people in your age group or in the age group below yours?

45-49

A pyramid shows the history of a country's population growth. In the United States from 1945 to 1965, people had larger families. These people are now between the ages of 30 and 50 and are called baby boomers. This pyramid is an example of slow population growth.

Short-term fluctuations often can be traced to Short-term fluctuations often can be traced to such historical events as wars, epidemics, such historical events as wars, epidemics, economic booms, or depressionseconomic booms, or depressionsBaby Boom-after WWIIBaby Boom-after WWIIGreat Depression-decline in birth rate 1930 and Great Depression-decline in birth rate 1930 and 19341934World Wars I and II-deficit of men in GermanyWorld Wars I and II-deficit of men in GermanyThe impact of these events emphasizes the The impact of these events emphasizes the interrelationships among population change and interrelationships among population change and economic, social, political, and health factors.economic, social, political, and health factors.

1.How is Congo's pyramid different from that of the U.S.?

2.Which age group in Congo is the largest?

3.What proportion of the population is in this age group?

There are more people in the younger age groups

Almost 20% (9% female and 9% male)

1. Now look at Germany. How is it different?

2. How is it different from Congo?

The age groups are closer to being equal

There is a greater proportion of older people

Why do we need this information?Why do we need this information?

Why would a country 's leaders want to know Why would a country 's leaders want to know the proportion of the population in different age the proportion of the population in different age groups? groups? What difference does the age of the people in What difference does the age of the people in a country make? a country make? What kinds of products do young people use? What kinds of products do young people use? What kinds of services do they need? What kinds of services do they need? What about older people? What about older people? Is it important for a government leader or Is it important for a government leader or planner to know the age of the population they planner to know the age of the population they are serving? are serving?

Young people –Schools, and later, jobsYoung people –Schools, and later, jobs

Older people- retirement systems and Older people- retirement systems and medical facilities medical facilities

As a population ages, needs change from As a population ages, needs change from childcare and schools to jobs, housing, childcare and schools to jobs, housing, and medical care. and medical care.

Migration also affects pyramid shapeMigration also affects pyramid shape Most migrants are in the working ages, Most migrants are in the working ages, and often more males than females and often more males than females In some Middle Eastern countries a large In some Middle Eastern countries a large number of men migrated to work in the oil number of men migrated to work in the oil fields, which caused a bulge in one side of fields, which caused a bulge in one side of the pyramid, while it took a "bite" out of the the pyramid, while it took a "bite" out of the pyramid of some of the countries from pyramid of some of the countries from which they came. which they came.

Time to make your own Population Time to make your own Population PyramidsPyramids

We will use a modified pyramid with only 4 We will use a modified pyramid with only 4 age groupsage groups

First we will practice with the U.S.First we will practice with the U.S.

After we are done, you will get in groups of After we are done, you will get in groups of 4 and graph pyramids of other countries4 and graph pyramids of other countries

US Population by Age 2000 (percent)

AGES MALES FEMALES

0-19 15% 14%

20-39 15% 14%

40-59 13% 13%

60+ 7% 9%

60+

40-59

20-39

0-19

30 25 20 15 10 5 0 5 10 15 20 25 30

Percent of Population

Now get with your Now get with your partners and make partners and make

your population your population pyramidspyramids

PolandPolandHaitiHaitiThailandThailandItalyItalySaudi ArabiaSaudi ArabiaBrazilBrazilAustraliaAustraliaEthopiaEthopiaJapanJapanCanadaCanadaArgentinaArgentinaKenyaKenyaGermanyGermanySouth KoreaSouth KoreaIndiaIndiaNigeriaNigeriaCubaCubaLithuaniaLithuania

EgyptEgyptUnited KingdomUnited KingdomChinaChinaMexicoMexicoDem. Rep. of CongoDem. Rep. of CongoFranceFranceBangladeshBangladeshIranIranIndonesiaIndonesiaIrelandIrelandCyprusCyprusPakistanPakistanSri LankaSri LankaVietnamVietnamRomaniaRomaniaHondurasHondurasPapua New GuineaPapua New GuineaHungaryHungary