Grade 9 Academic Geography – Strand 3

Population Pyramids

Expansive — A broad base, indicating a high proportion of children, a rapid rate of population growth, and a low proportion of older people. Nunavut is an example of an expansive type population pyramid.

Stable growth — A structure with indentations that even out and reflect slow growth over a period. Northwest Territories is an example of a stable type population pyramid.

Stationary — A narrow base and roughly equal numbers in each age group, tapering off at the older ages. Manitoba is an example of a stationary type population pyramid.

Declining — A high proportion of aged persons and declining numbers. Newfoundland and Labrador is an example of a declining type population pyramid.

The Population Pyramid and “How it works”

Bar graphs are a handy way to illustrate numbers. Displaying two bar graphs together, horizontally and as a mirror image, we make a Population Pyramid (see Figure 1).

Figure 1. Population Pyramid for Canada, 1961

You should see the following features in Figure 1.

·  The pyramid narrows toward the top. This is because the death rate is higher among older people than among younger people.

·  There are also a few bulges and narrower parts in the middle part of the pyramid. For example, there are not as many people in their 20s as in their 30s in Canada in 1961. The people in their 20s in 1961 were born at the end of the Depression and the start of WWII. This was a time of economic hardship and uncertainty. People were having fewer children in this period.

·  In 1961, the pyramid had a wide base. Adding the percentages for the three lowest age groups, we find that 35% of the population was under 15. These are the “baby boomers,” a large group of people born between 1947 and 1966 when the economy was growing and prospering.

Task - 2001 Population Pyramid for Canada

Data are provided from the 2001 Canadian Census of Population giving the population by five-year age groups and sex. Using the data, make a 2001 Population Pyramid on graph paper. Males and Female go across the bottom (X-axis) of your graph while ages are on the Y-axis with 0-4 at the bottom.

Canada’s Population by Age Group and Sex 2001
Census of Population
Age Group / % Men / % Women
0-4 / 2.9 / 2.8
5-9 / 3.4 / 3.2
10-14 / 3.5 / 3.3
15-19 / 3.5 / 3.3
20-24 / 3.3 / 3.2
25-29 / 3.1 / 3.2
30-34 / 3.4 / 3.6
35-39 / 4.1 / 4.3
40-44 / 4.2 / 4.4
45-49 / 3.8 / 3.9
50-54 / 3.4 / 3.5
55-50 / 2.6 / 2.7
60-64 / 2.1 / 2.2
65-69 / 1.8 / 2.0
70-74 / 1.5 / 1.8
75-59 / 1.1 / 1.6
80-84 / 0.6 / 1.1
85-89 / 0.3 / 0.6
90+ / 0.1 / 0.3

Questions

Use your 2001 Population Pyramid to answer the following questions.

1.  Write the details of your age group and sex within the
Canadian population

Age group ______Sex ______Percentage ______

2.  What single age group and sex represents the largest percentage
of Canada’s population?

Age group ______Sex ______Percentage ______

3.  Circle the 10-year age group that contains the largest percentage of the population.

0-910-1920-2930-39 40-49

4.  What percentage of Canada’s population is male and what percentage is female? (Add the percentages for each sex.)

Males______Females______

5.  Write in the percentage for males and females age 65 and over.

Males______Females______

Comments

6.  Explain why the 2001 population pyramid has a narrower base
than that of the 1961 pyramid (Figure 1).

7.  Populations are frequently divided into two categories: (1) people who are of working-age (15-64) and (2) people who are not of working age (under 15; 65 and over). Give the percentage for each category in 2001:

Working age ______

Not of working age ______

How could the working-age population contribute to Canada’s economic growth? List five examples.

Why is it important to understand or examine the changing trends in working-age populations (i.e., compare 1961 to 2001)?

8.  Why would leaders of a country want to know the proportion of the population in different age groups? What difference does the age of the people in a country make? Provide three examples.

Another element of Population Pyramids is Total Fertility Rates (TFR). It is the single most important factor in determining future population.

TFR is the average number of babies born to women during their reproductive years OR the sum of the age-specific birth rates of women in five-year age groups. Note - Fertility rate is the number of children born alive per thousand fertile women per year.

·  A TFR of 2.1 is considered the replacement rate. Once TFR reaches 2.1, the population will remain stable assuming no immigration or emigration takes place.

·  When TFR is greater than 2.1, a population will increase.

·  When it is less than 2.1, a population will decrease, although due to the age structure of a population it will take years before a low TFR is translated into lower population.

TFR has been declining dramatically over the past decade. For example. Canada’s TFR is below the replacement rate. Worldwide in 2000, 61 countries have a TFR of 2.1 or less. Canada’s 1998 TFR was 1.7, while Niger had the world’s highest TFR at 8.0 children.

How do you calculate TFR?

This is the data for Canada.

·  Divide Number of Live Births / Female Population in the Age Group to determine the Age Specific Birth Rate

·  Sum the Age Specific Birth Rates

·  Multiply by 5 to calculate the TFR.

Table 1.

Age of Mother / Number of Live Births / Female Population in the Age Group / Age Specific Birth Rate
10-14 / 367 / 387 341 / 0.0009
15-19 / 15 267 / 408 422
20-24 / 30 613 / 403 191
25-29 / 42 245 / 397 398
30-34 / 39 105 / 446 488
35-39 / 17 378 / 469 810
40-44 / 2 808 / 458 439
45-49 / 94 / 413 377
SUM

The TFR is the sum of the age-specific birth rates multiplied by five. What is Canada’s TFR?

From the above information, is Canada’s childbearing population is replacing itself? Provide an explanation with your answer.

We know the TFR for the developing countries is slightly above replacement. Now, let us look closer at various regions and incomes

Table 2. TFR, HDI and Incomes for Various Regions of the World

Factors / 1970 TFR / 2000 TFR
Least Developed / 6.6 / 5.1
Arab States / 6.7 / 3.8
East Asia and Pacific / 5.0 / 2.0
Latin America and Caribbean / 5.1 / 2.5
South Asia / 5.6 / 3.3
Sub-Saharan Africa / 6.8 / 5.4
Central and Eastern Europe / 2.5 / 1.4
High Human Development / 2.5 / 1.8
Medium Human Development / 4.9 / 2.4
Low Human Development / 5.8 / 5.6
High Income / 2.2 / 1.7
Middle Income / 4.6 / 2.1
Low Income / 5.7 / 3.7

Question

Provide an interpretation of Table 1 and Table 2. Include three ideas for each table.