1. Measuring Population Change
Population Growth
Population Pyramids

2. Population
2 aspects of a population that demographers most want to know are the population’s size and its rate of change.
Demographers measure population change in both absolute and relative terms.

3. Population Change
Absolute population change is a measurement of the actual number of people by which a population increases or decreases.
The relative population change is a percentage of original total population
The relative population change is often referred to as the population growth rate because populations seldom decrease in size.

4. Factors Affecting Population Change
Population change is calculated using the following equation:
Births + Immigration – Deaths - Emigration

5. Migration
Immigration is the movement of people into a new country of residence.
Emigration is the movement of people out of an old country of residence.
There are many factors that may direct people to migrate, but all factors can be characterized as either push or pull factors.

6. Migration
Main pull factors are the related to the search for a better life. It may be the promise of better health care, lower taxes, higher salary, better education, or more people of similar culture and beliefs; all are good examples of why someone may be attracted to a new country.
Thousands of people immigrate to Canada each year in search of a better life with good health care, social services, and a rich diversity of culture.

7. Migration
Some examples of push factors would be persecution, war, drought, flooding, famine, and other natural hazards that force people out of their former home country into another for safety and shelter.
People who have been displaced by a threat to their human rights are called refugees and are given special immigration status as refugees.

8. Births and Deaths
Outside of the continuous moving of peoples around the world from country to country. The rate of natural increase (RNI) is based solely on the birth rate and death rate in a given country.
Birth rates(BR), death rates(DR), and the RNI are all measured per 1000 people.

9. Births and Deaths Birth rates are influenced by the following factors:
The number of women in the given population;
The average age of the women in the given population;
Culture and religious practices in the region;
General level of health care in the region;
Economic status and the education of women in the population;
Families with low incomes tend to have more children in order to generate more income for the family.

10. Births and Deaths
Mortality rates are influenced by the following factors:
Availability and quality of medical services
Education, particularly in the case of women, is key to ensuring the public are practicing healthy living
Availability of food and clean water
War and environmental hazards

11. Total Fertility Rates and Replacement Levels
Total fertility rates are the average total number of children had by women in a particular country.
Total fertility rates are estimated depending on the culture, religion, and economic status of the average woman in the country.
The replacement level is the total fertility rate necessary to maintain the population of a country without migration.
In MDC’s it is about 2.1 children per female
In LDC’s it is about 2.5 children per female