Population Growth
Changes in world Population
The world population is the total number of living humans on Earth at a given time. As of July 2008, the world's population is estimated to be just over 6.684 billion. In line with population projections, this figure continues to grow at rates that were unprecedented before the 20th century, although the rate of increase has almost halved since its peak of 2.2 percent per year, which was reached in 1963. The world's population, on its current growth trajectory, is expected to reach nearly 9 billion by the year 2042.
The world population is the total number of living humans on Earth at a given time. As of July 2008, the world's population is estimated to be just over 6.684 billion. In line with population projections, this figure continues to grow at rates that were unprecedented before the 20th century, although the rate of increase has almost halved since its peak of 2.2 percent per year, which was reached in 1963. The world's population, on its current growth trajectory, is expected to reach nearly 9 billion by the year 2042.
Factors affecting the population
The Birth RateIt is the average number of the children born in a country compared to the rest of the population. In other words, it is the number of births for every 1000 people in the country.
Birth rate=Number of live births
X 1000Total population
Factors affecting the birth rate in a country
The Death RateThe number of people who die each year compared to every 1000 people in the population is known as death rate.
Death rate=number of deaths
X 1000Total population
Factors affecting Death rate in a country
Net MigrationEmigration is when a person moves out of the country.
Immigration is when a person moves into a country.
Net Migration is the difference between emigration and immigration.
If net immigration is positive it will lead to a population increase, a negative net immigration will lead to a fall in population of the country.
Dependency RatiosIt is the number of people in work with the total population of the country.
Dependency ratio =Total Population
Number of people in work
Dependent Population usually consists of children, students, housewives, the unemployed and old age pensioners.
Affects of increase in dependent populationLower standard of living
An increase in the dependent population will mean that people in work have more people to support and thus the living standard of the country will fall.
Balance of trade
If the people in work cannot produce enough goods and services to satisfy the need of the growing dependent population then the country has to spend its income on importing these goods and services, which will lead to an unfavourable balance of trade.
The Birth RateIt is the average number of the children born in a country compared to the rest of the population. In other words, it is the number of births for every 1000 people in the country.
Birth rate=Number of live births
X 1000Total population
Factors affecting the birth rate in a country
- Existing age-sex structure
- Availability of family planning services
- Social and religious beliefs - especially in relation to contraception and abortion
- Female employment
- Economic prosperity (although in theory when the economy is doing well families can afford to have more children in practice the higher the economic prosperity the lower the birth rate).
- Poverty levels – children can be seen as an economic resource in developing countries as they can earn money
- Infant Mortality Rate – a family may have more children if a country's IMR is high as it is likely some of those children will die.
- Conflicts
- Typical age of marriage
The Death RateThe number of people who die each year compared to every 1000 people in the population is known as death rate.
Death rate=number of deaths
X 1000Total population
Factors affecting Death rate in a country
- Medical facilities and health care
- Nutrition levels
- Living standard
- Access to clean drinking water
- Hygiene levels
- Levels of infectious diseases
- Social factors such as conflicts and levels of violent crime
Net MigrationEmigration is when a person moves out of the country.
Immigration is when a person moves into a country.
Net Migration is the difference between emigration and immigration.
If net immigration is positive it will lead to a population increase, a negative net immigration will lead to a fall in population of the country.
Dependency RatiosIt is the number of people in work with the total population of the country.
Dependency ratio =Total Population
Number of people in work
Dependent Population usually consists of children, students, housewives, the unemployed and old age pensioners.
Affects of increase in dependent populationLower standard of living
An increase in the dependent population will mean that people in work have more people to support and thus the living standard of the country will fall.
Balance of trade
If the people in work cannot produce enough goods and services to satisfy the need of the growing dependent population then the country has to spend its income on importing these goods and services, which will lead to an unfavourable balance of trade.