It’s All About People!
Demography is the study of populations. It helps answer
questions such as:
Why are more schools closing than opening?
Why will you likely have to work more years than your
parents before retiring?
Why are old rock-and-roll groups, such as the Rolling
Stones, still so popular?
How do we compare countries that have populations of
We use RATES, not NUMBERS!
Look at the number of births for these
Canada: 330,000 babies born in 2003
Russia: 1,458,000 babies born in 2003
Togo: 191,000 babies born in 2003
To calculate each country’s birth rate,
divide the number of births in one year by
the population, and multiply the result by
• Canada (330 000 / 32 207 000) 1000 = 10
• Russia (1 458 000 / 144 526 000) 1000 = 10
• Togo (191 000 / 5 429 000) 1000 = 35
In a similar fashion, rates can be calculated for:
•number of deaths
•number of immigrants
•number of emigrants MORE
Rates can also be combined in the following
• natural increase rate = birth rate –
• net migration rate = immigration rate – Oh
emigration rate come
Population Growth Rate
A country’s population growth rate
= natural increase rate + net
Canada’s Population Growth Rate
What’s your thesis?
The thesis is the big idea; it’s the key to any
persuasive piece of writing.
It's the point you want to prove.
It's the focus of the whole thing.
Everything you do in the piece should grow from
your thesis--that's how important it is.
So, here’s the statement:
The rate at which a country’s population grows or
declines has an enormous influence on people’s lives.
Come up with a thesis statement that agrees or
disagrees with the statement.
Comparing Population Growth Rates
These population growth rates may not seem
• Canada - 0.8%
• Russia – 0.4%
• Togo - 2.4%
But we need to consider the impact of
The Power of Compounding
To help pay for your future education costs, your parents
offer you two choices. For 30 days, you can receive one
of the following:
»Fig. A $1000 + $1000 + $1000 + $1000 … »Fig. B 1 cent + 2 cents + 4 cents + 8 cents …
Which one would you chose: Fig. A or Fig. B?
If you selected Fig. B, you would have a lot more money
for your education. Why? Because growth occurs on top
of the growth that has already taken place.
»Fig. A $30 000 »Fig. B $10 737 418.23
Here is the impact of compounding on the populations of
Canada, Russia, and Togo for the next 100 years.
Doubling time is the time it takes a
population to double at its current growth
• You could calculate doubling time with I’m
fancy mathematics… leaving!
• Or, you could estimate the time by…
…using the Rule of 70, which
states that doubling time
is equal to 70 divided by the
population growth rate.
Canada’s population growth Fine. I’ll
rate is 0.8%. stay!
Therefore, Canada’s doubling
time is approximately 87
• Canada’s doubling time is 87 years.
• Togo’s doubling time is 30 years (70/2.4).
Which country can more easily deal with its population
It is easier and faster to
structure if the data are
Two bar graphs are
The first one looks like this.
The second bar
graph looks like
Combine the two sets of bar graphs to create a
population pyramid that shows the age/gender
breakdown of a country’s population.
The dependency load is the part of the population that
needs to be supported. It is made up of two components:
the 0–14 age groups and the 65+ age groups.
What has happened to the dependency load between
1956 and 2004?
What is the significance of this change?
Stages of Population Change
Populations within countries change over time in a