POPULATION PYRAMIDS!
You’ll be learning about population pyramids & you will use data from the United States to
construct population pyramids and analyze population trends.
Please follow the steps below to complete the assignment correctly. If you have any questions,
let me know.
Step 1: Watch the TEDEd video on population pyramids… I’ve included the link below.
https://www.youtube.com/watch?v=RLmKfXwWQtE&t=169s
Step 2: Watch the PowToon video on population pyramids… I’ve included the link below. I like
the song, dance if you want to :)
https://www.youtube.com/watch?v=9gejJKbpqnM
Step 3: Read the Population Pyramid PDF I’ve attached below (USA Aging Population Pyramids).
Step 4: Using the data on the 3rd page of the PDF (left side), construct 5 population pyramids
according to each year (use the sheet that I’ve given you).
Step 5: Using the data that you see on the 5 population pyramids that you created, answer the
questions on the back of the page. They are the same questions listed on the 2nd page
of the PDF.
Introduction:
Population pyramids help us observe the distribution of age groups within a population. The relative size of one age group compared to another can have important social,
economic, and political consequences. This activity involves construction and analysis of a series of population pyramids for the United States, past, present, and anticipated future.
Reading Population Pyramids:
A population pyramid graphically displays a population’s age and sex
composition. By showing numbers or proportions of males and females in each age group, the pyramid creates a “picture” of a population’s basic
characteristics. Pyramids based on proportions or percent of population in each age-sex group (called cohorts) are best for comparing populations of
different sizes. The sum of all the age-sex cohorts in the population pyramid equals 100 percent of the population.
A population pyramid is a simple bar graph constructed around a central
axis, with bars to the left most commonly representing males, and those to the right, females. Each horizontal bar represents the size of an age-sex
cohort as a percent of the total population. In the graph to the left, the bottom bar shows the percent of males and females who were under five
years of age in 1990; the bar located at ages 30–34 on the pyramid represents all those alive and living in the United States in 1990 who were in that age
cohort; and so forth up to the pyramid’s top. Each year a new cohort is born and “appears” at the bottom of the pyramid, while the cohorts above it move
up. As cohorts age, they inevitably lose members because of death, and may gain or lose because of migration.
Constructing Population Pyramids:
A simplified population pyramid can be constructed using age-sex data in ten-year cohorts.
Working individually or in groups (as instructed), use data for 1940, 1960, 1980, 2000, or 2020 and the blank pyramid grid, provided on Activity Two Worksheet, to construct
time-series population pyramids for the United States. For example, for 1940, in the grid section at the bottom of the pyramid blank, labeled “under 10 years” shade the left side of the grid
to reflect the percent of the population that was male, and the right side of the grid, the percent female, using different colors for males and females. Then repeat this step for each
ten-year cohort, maintaining the same colors for all males and all females.
Activity Two
Graphing Aging in the
United States —
National Patterns
Materials:
Activity Two Worksheet Colored pencils
Vocabulary:
Population pyramid Cohort Aging populationObjectives:
This activity involves...
▲construction of population pyramids
▲interpretation of population pyramids
▲evaluation of aging trends in the U.S. over time
▲speculation about the socio-economic implications of aging for the United States
1 2 3 4 5 5 4 3 2 1 0
85 and over 80 – 84 75 – 79 70 – 74 65 – 69 60 – 64 55 – 59 50 – 54 45 – 49 40 – 44 35 – 39 30 – 34 25 – 29 20 – 24 15 – 19 10 – 14 5 – 9 Under 5
Males FemalesFemales
Population of the United States, 1990
Source: US Bureau of the Census
(percent) (age in years)
Interpreting Population Pyramids:
A population pyramid can tell a great deal about a population at a glance. Its shape can
give significant clues to a population’s past and future. For example, the pyramid on the front of this page reveals a slight majority of males at the very youngest ages. This is
because there are about 105 males born for every 100 females. But the top of the pyramid shows that females comprise a majority. This is because females typically outlive males.
Pyramids may reveal a postwar “baby boom,” as well as an “echo” effect as baby boomers start to have kids of their own. Pyramids also show the relationship between the
“dependent” population (under 20 and over 64 years) and the “economically productive” population (between 20–64 years). As the U.S. population becomes older, there will be an
imbalance between the “dependent” and “productive” populations, which could have serious implications in the coming years, particularly for retirement and health care
systems.
In summary ...
Analyze pyramids for the United States from 1940–2020. Then discuss the following questions.
▲ What patterns can be observed in this series of pyramids?
▲ When is the “baby boom” first observed?
▲ Trace the movement of the “baby boom” generation through the pyramids. What
effects — social, economic, political — has this generation had on the country over
the years?
▲ When will the “baby boom” generation reach retirement age? How will this affect the
“dependency ratio”?
▲ What are some social, economic, and political issues that are likely to emerge as the
U.S. population ages?
Activity Two
(continued)
Aging in the United States
is an education module developed by the Population Reference Bureau
Draw your population pyramid below:
Pyramid Data — (Percent)
1940 Male Female
Under 10 years 8.18 7.94 10 to 19 years 9.21 9.07 20 to 29 years 8.46 8.77 30 to 39 years 7.46 7.57 40 to 49 years 6.55 6.39 50 to 59 years 5.14 4.81 60 to 69 years 3.26 3.22 70 years and over 1.91 2.05
1960 Male Female
Under 10 years 11.02 10.65 10 to 19 years 8.53 8.28 20 to 29 years 6.08 6.13 30 to 39 years 6.67 6.91 40 to 49 years 6.15 6.35 50 to 59 years 4.93 5.11 60 to 69 years 3.51 3.92 70 to 79 years 1.97 2.37 80 years and over 0.58 0.83
1980 Male Female
Under 10 years 7.42 7.09 10 to 19 years 8.82 8.48 20 to 29 years 9.12 9.05 30 to 39 years 6.94 7.08 40 to 49 years 4.89 5.12 50 to 59 years 4.87 5.36 60 to 69 years 3.78 4.54 70 to 79 years 2.08 3.05 80 years and over 0.75 1.54
2000 Male Female
Under 10 years 7.24 6.91 10 to 19 years 7.43 7.07 20 to 29 years 6.64 6.51 30 to 39 years 7.57 7.63 40 to 49 years 7.59 7.79 50 to 59 years 5.37 5.73 60 to 69 years 3.40 3.89 70 to 79 years 2.53 3.34 80 years and over 1.12 2.21
2020 Male Female
Under 10 years 6.90 6.57 10 to 19 years 6.78 6.44 20 to 29 years 6.72 6.60 30 to 39 years 6.43 6.57 40 to 49 years 5.67 5.93 50 to 59 years 6.08 6.46 60 to 69 years 5.63 6.16 70 to 79 years 3.34 3.87 80 years and over 1.45 2.39
Activity Two Worksheet:
Graphing Aging in the United States — National
80 and over
____________________________________________________________________________________
70 – 79
____________________________________________________________________________________
60 – 69
____________________________________________________________________________________
50 – 59
____________________________________________________________________________________
40 – 49
____________________________________________________________________________________
30 – 39
____________________________________________________________________________________
20 – 29
____________________________________________________________________________________
10 – 19
____________________________________________________________________________________
Under 10
Males
age in years
percent
Females
I I I I I I I I I I I I I
12 10 8 6 4 2 0 2 4 6 8 10 12
