A working knowledge of the basic vocabulary of population geography is required in order for students to master important underlying concepts. Likewise, students need to understand the mathematical relationships implicit in population statistics and the broader social and economic implications of such relationships. Students should be able to present demographic data in a graphic format that supports analysis and interpretation.
- To develop a working vocabulary for population geography
- To understand relationships and implications of demographic data
- To construct and analyze population pyramids at different scales
AP Human Geography*: Unit II—Population Unit
A. Geographical analysis of population
1. Density, distribution, and scale
3. Patterns of composition—age, sex, race, and ethnicity
- Activity 1: World Population Data Sheet at a Glance
- Activity 2: Working with Demographic Data
- Activity 3: Constructing and Interpreting Age-Sex Graphs
- Activity 4: How to use MS Excel to Construct Age-Sex Pyramids
Activity 1: The World Population Data Sheet at a Glance
Find answers to the following questions using the current World Population Data Sheet. Provide students with blank world maps and have them locate, shade, and label the countries identified in the questions that follow.
- What is the current population of the world?
- Rank, in descending order, the 10 countries with the largest population.
Rates are often used, instead of absolute numbers, to determine how frequently a population or demographic event is occurring—rates show how common an event is. Rates also make it possible to compare countries that vary greatly in terms of population size.
The crude birth rate (CBR) is the annual number of births per 1,000 population.
- Which country has the highest CBR? Which country has the lowest?
The crude death rate (CDR) is the annual number of deaths per 1,000 population.
- Which country has the highest CDR? Which country has the lowest?
The infant mortality rate measures the number of deaths each year to infants under 1 year of age per 1,000 live births.
- Which country has the highest infant mortality rate and what is that rate? Which country has the lowest and what is that rate
The total fertility rate (TFR) is the average number of children a woman would have if she maintained today’s level of childbearing throughout her reproductive years.
- Which countries share the highest TFR and what is it? Which countries share the lowest TFR. What is it?
The age and sex structure of a population refers to the number or proportion of males and females who are in each age category. Age-sex structure tells us about a population’s past trends in fertility, mortality, and migration. It also provides information about the population’s potential for future growth. The greater the proportion of people in the younger-adult age groups, the greater the potential for more births and population growth.
- Which country has the “youngest” population, that is, the highest proportion of population under age 15? Which country has the “oldest” population, that is, the highest proportion of population over age 64?
- In which country are people expected to live the longest? Which country has the lowest life expectancy?
- Which African country has the highest proportion of people living in urban areas? In Asia? In Latin America? In Europe? In Oceania?
Gross national income in purchasing power parity per capita (GNI PPP/capita) converts income into “international dollars” and indicates the amount of goods and services one could buy in the United States with a given amount of money.
- Which country is the wealthiest in terms of GNI PPP/capita? Which is the second wealthiest? Which are the poorest two countries?
A population grows because there are more births than deaths or more people are moving in than moving out. The difference between births and deaths is expressed as a percentage called the rate of natural increase.
- Which major region is growing the fastest through natural increase? Which major region is growing at the slowest rate? Within the major regions identified, which subregions are growing fastest? … slowest?
- Which country is growing the fastest through natural increase? Which country is growing at the slowest rate?
A population projection is a computation of future changes in population numbers based on assumptions about future trends in fertility, mortality, and migration.
- Rank the 10 countries with the largest projected populations for both 2025 and 2050 (in descending order).
- Which country (ies) is projected to drop out of the top 10 by 2050? Which country (ies) is projected to be added to the top 10?
- Rank the major regions according to population size (in descending order) for the present, for 2025, and for 2050. What trend can be observed in terms of population change?
Based on the information collected (above) from the current World Population Data Sheet, write an essay (1-2 pages) discussing current patterns and trends in population at global, regional, and national scales. Be sure to support any generalizations with specific examples from the data sheet.
Activity 2: Working With Demographic Data
Use the current World Population Data Sheet to answer the following questions:
- China and India have the largest populations in the world. Which of these two countries adds more people to its population annually? [Calculate the numbers added by applying the rate of natural increase to the population of each country. Hint: the rate is a percent]
- What proportion of the world’s people live in Africa? In Asia? In North America? In Latin America? In Europe? In Oceania? What are the projected proportions by 2025 and 2050?
Construct a bar chart showing the regional distributions of the world’s population for the current year, 2025, and 2050.
What trends are reflected in the bar chart?
- What proportion of the world’s people live in less developed countries (LDCs) in the current year? In more developed countries (MDCs)?
What proportion of the world’s people is projected to live in LDCs in 2025? In 2050? What proportion is projected to live in MDCs in 2025? In 2050?
Discuss as a class the economic and social implications of the changing proportions of the world’s people in LDCs and MDCs.
- Examine the crude birth rate, crude death rate, and rate of natural increase of any three countries listed on the World Population Data Sheet. Discuss as a class the mathematical relationship among these three rates.
The age-dependency ratio is the ratio of persons in the “dependent” ages (under 15 and over 64 years) to those in the “economically productive” ages (15-64 years) in a population. The age-dependency ratio is often used as an indicator of the economic burden the productive portion of a population must carry—even though some persons defined as “dependent” are producers and some persons in the “productive” age range are economically dependent.
The formula for this ratio:
|% of population under age 15 + % of 65 and over||X 100|
|% of population ages 15-64|
[Hint: The three percents will equal 100%. ]
The age-dependency ratio in the United States in 2004 was:
|21% + 12%||X 100|
This means that there were 49 people in the dependent ages for every 100 people of working age.
Select 2 LDCs and 2 MDCs from the data sheet and compute the age-dependency ratios for each. Discuss student responses in class. What factors do you think contribute to a high age-dependency ratio? What are some economic and social consequences of a high age-dependency ratio?
Activity 3: Constructing and Interpreting Age-Sex Graphs
What Is an Age-Sex Graph?
An age-sex graph, commonly referred to as a population pyramid even though the graph for some countries is not actually a pyramid shape, displays a population’s age and sex composition. Horizontal bars represent the numbers or proportions of males and females in each age group, or cohort. The sum of all the age-sex cohorts in the population pyramid equals 100 percent of the population. Cohorts may vary from single years to groups of years.
The left side of the pyramid represents the male population and the right side, the female population. The bars at the bottom of the pyramid represent the percent of the population that is male, 0-4 years old (left) and the percent of the population that is female, 0-4 years old (right). Each bar above the base represents the next five-year cohort, male and female, in the population. As cohorts age, they inevitably lose members because of death and they may gain or lose members because of migration. After age 45 the loss of population accelerates, causing the narrowing peak of all population pyramids.
Population pyramids reveal a great deal about a population at a glance. Populations of countries can differ markedly as a result of past and current patterns of fertility, mortality, and migration.
Part One: How Do You Construct an Age-Sex Graph?
In order to understand how to interpret population pyramids, read the following selections from PRB publications:
- Population Handbook, 5th edition
- Population: A Lively Introduction, 3rd edition , pp. 23-28.
- Provide each student with a copy of the “Age-Sex Graph” handout, colored pencils, and the age-sex data table. Also transfer a copy of the graph to a transparency for use as a demonstration.
- Explain that the raw population numbers need to be converted to percents before beginning to construct a pyramid. This can be done using a calculator or using a spreadsheet, such as MS Excel. [Divide the population of each cohort by the total population of the country to determine what percent of the total population is in each cohort.]
- Using the graph transparency, demonstrate how to transfer the data (%) for the first pyramid by drawing the bar for the first male cohort (0-4 years) to the left, and for the first female cohort (0-4 years) to the right. Have students proceed on their own, completing pyramids for both country A and country B.
- When students have completed both pyramids, lead a discussion of the similarities and differences in the shapes of the two pyramids. Based on the readings noted above, what inferences can be drawn about social and economic circumstances in each country? What might be some reasons for the differences in the two pyramids?
In this activity students will analyze demographic data for selected countries of the world. They will also construct population pyramids and speculate on differences in the quality of life in these countries.
- Assign students (or pairs of students, depending on class size) one country from the list below. Direct students to locate the most current age-sex data for their assigned country.
Column AColumn B
Argentina Bangladesh France Brazil Germany Egypt Israel Ethiopia Japan Indonesia New Zealand Thailand Russia Turkey United Kingdom Vietnam
Open the U.S. Census Bureau “International Database,” available at: www.census.gov/ipc/www/idbnew.html
Choose “Summary Demographic Data.”
Select the assigned country from the country list. Then “Submit Query.”
Print or copy the data for the country. [Note: Disregard pyramids that appear on the Census IDB site. These are based on absolute numbers and are not appropriate for use in this activity.]
Use the Census Bureau website to complete the chart below for the assigned country.
|Birth Rate (per 1,000)|
|Death Rate (per 1,000)|
|Natural Increase (%)|
|Infant Mortality Rate (per 1,000 live births)|
|Total Fertility Rate|
|Population <15 yrs. (%)/>65 yrs. (%)|
|Life Expectancy at Birth (male/female)|
|Urban Population (%)|
- Construct a pyramid for the assigned country either manually using a copy of the graph template, or by following the steps for pyramid construction using MS Excel (see instructions provided under Materials Needed).
- Compare the demographic variables and the pyramid for the country. How does the pyramid reflect the variables? [for example, how is Birth Rate reflected in the base of the pyramid?]
- Characterize the level of development in the country—high, medium, low? Use two specific examples from the table and pyramid to support the decision about level of development.
- Have students with pyramids in the “a” group compare their pyramid with a pyramid from the “b” group. Have them also compare the demographic variables for both countries. What generalizations can be made concerning demographic indicators and level of development? [for example, if the birth rate is high, then the level of development is…] Encourage students to form at least three generalizations that are supported by the pyramids and data charts.
- Lead a class discussion on the use of population data and graphs as tools for analysis of population structure and composition. Describe the age/gender patterns you observe. Discuss the implications of the patterns. Think about the kinds of problems that could occur because of the differences in lifestyle and community priorities for different age groups in each location. Identify some investments (stores, entertainment, etc.) that might do well or some social programs (child care, education, medicine, etc.) that might be required in places with these populations.
Activity 4: How to Use MS Excel to Make an Age-Sex Graph
Installing an Autoformat for a Population Pyramid in MS Excel
Copy the files above “Pyramid Blank” and “New Pyramid” to a disk or to the desktop of your computer.
- Open the “Pyrblank” file in your own copy of Excel. Then select “Save As” from the File menu. Under “Save as Type,” select “Template.”This will add the pyramid spreadsheet template to your copy of Excel.
- Open the saved “New Pyramid” in your own copy of Excel.
- select Chart type
- select “Custom types”
- select “User defined”
- select “Add” then type a “format name”: population pyramidand click ok
This will add the custom format for a pyramid to the list of options in your program.
Constructing a Population Pyramid Using Excel
Follow the steps below carefully and accurately to convey age-sex data into a five-year cohort population pyramid.
Click on the “Start” button (lower left). From “Programs,”
- Open Excel. Under File, select “New.” Open the template “Pyramid Blank.”
- In Col. E, cells2-17*, type the population for each male cohort.
- In Col. F, cells 2-17*, type the population for each female cohort.
- In Col. B, cell 24, type the total population for the country.
- Select Col. B, cell 2. Then click on the Formula Bar just above the column letters and type: =E2/$B$24*-100
Press Enter. Select Col. B, cell 2 again; then point to the small black box in the lower right corner of cell B2; click and drag down through cell B19. Release. [Note: All percents are negative order to make the bars representing the male cohorts to appear to the left of the center axis).
- Repeat step 5 for Col. C, using the formula: =F2/$B$24*100
- Highlight Col. A, B, and C, cells 1-19.
- Under Insert, select “Chart.” Select the tab “Custom Types” and then the option “User-defined.” From the User-defined options, select “New Pyramid.” At the on-screen prompt, click on “Next” until you reach “Step 4.” Select the option “As a new sheet,” then click “Finish.”
- Use the “text box” tool (on the tool bar at the bottom of the page) to add an appropriate title, include “where, what, and when.” Also use the text box tool to add a source note in the lower left corner below the pyramid. Save your work; then print.
* AP and the Advanced Placement Program are registered trademarks of the College Entrance Examination Board, which was not involved in the production of these lesson plans.