Demography and Global Population Trends

Population and Society

Demography is the study of population. It examines a population’s volume and the causes for its growth or decrease. This field is ruled by three primary factors: birth, death, and migrations.

The elements that influence these three factors are usually social and cultural in nature, which is why demography is considered a branch of sociology.

The Importance of Statistics

Statistics have great importance in the study of population. Nevertheless, statistics do not always reflect 100% real data, and this must be taken into account when studying the information.

Basic Demographic Concepts

• Birth rate: The number of annual births per 1,000 inhabitants.
• Fertility rate: The average number of births per 1,000 women of childbearing age.
• Mortality rate: The number of annual deaths per 1,000 inhabitants.
• Child mortality rate: The number of babies who die annually before reaching one year of age for every 1,000 births.
• Life expectancy: The average age of the population in a specific region.

Dynamics of the Population

The growth or decrease rate of a population is measured in the following way:

Number of births per 1,000 inhabitants - Number of deaths per 1,000 inhabitants = Growth or decrease rate of the population

Global Population Growth

There are European countries that reach negative birth rates; that is, their population decreases because there are more deaths than births.

• Many developed countries do not exceed a 0.5% growth rate.
• In developing countries, this rate can be between 2% and 3%.

This difference is very meaningful because demographic growth is exponential: with a growth of 3%, the population doubles in just 23 years.

Historical Growth Timeline

• 1850: 1,000 million
• 1930: 2,000 million
• 1975: 4,000 million

World Demographic Structure

The structure of the population is distinguished by the following categories:

• Industrialized countries: Low birth and mortality rates, leading to low fertility.
• Developing countries: High birth rates and descending mortality rates, leading to high fertility.

Sustainability and the Aging Population

Is this sustainable? The world population is aging. Between 2000 and 2050, the proportion of the planet's population over 60 will double, from 11% to 22%. In absolute numbers, this age group will increase from 605 million to 2,000 million in the course of half a century.

Migrations

Migration is the act of crossing the boundary of a political or administrative unit for a minimum period of time. Migratory movements result in demographic changes with important social and economic effects. Migration may be internal or international.

Categories of Migrants

• Temporary migrant workers
• Highly qualified and professional migrants
• Irregular migrants
• Refugees
• Forced migration
• Asylum seekers
• Return migrations
• Family reunification