The concept and purpose of the Demographic Transition Model

The Demographic Transition Model (DTM) is a theoretical framework that illustrates how a country's population changes over time. Based on historical patterns observed in the UK since the 1700s, this model uses a graph to track shifts in birth and death rates, as well as total population, to explain demographic trends.

Key definitions related to population changes

Understanding the DTM requires familiarity with several fundamental terms that describe population dynamics.

Core terms in the Demographic Transition Model

• Birth rate - The number of live births per 1000 people in a population each year.
• Death rate - The number of deaths per 1000 people in a population each year.
• Natural increase/decrease - The difference between the birth rate and death rate, often expressed as a percentage.
• Total population - The overall number of people in a country, influenced by natural increase or decrease and migration.
• Migration - The movement of individuals from one location to another.

The stages of the Demographic Transition Model

The DTM is divided into five distinct stages, each representing a different phase of population change based on the balance between birth and death rates.

Overview of the five stages

Factors influencing birth and death rates in each stage

Each stage of the DTM is shaped by specific social, economic, and health-related factors that influence birth and death rates.

Stage 1 - High fluctuating

• High death rate - Disease and poor living standards.
• High birth rate - Children support the family, and many are born to ensure some survive infancy.

Stage 2 - Early expanding

• Falling death rate - Improvements in healthcare and standards of living.
• Sustained high birth rate - Birth rate remains high due to cultural and economic factors.

Stage 3 - Late expanding

• Declining birth rate - Infant mortality falls due to better healthcare, and women are being educated and choosing to have fewer children.
• Continued fall in death rate - Death rate continues to fall before levelling off.

Stage 4 - Low fluctuating

• Low birth rate - Children are expensive, and families decide to have fewer children.
• Low death rate - Excellent healthcare and high standards of living are enjoyed.

Stage 5 - Decline?

• Rising death rate - As the population ages, with large numbers of people reaching old age, the death rate starts to become higher than the birth rate.
• Very low birth rate - Birth rate is lower than the death rate.

The current stage of the UK and future predictions

The UK is currently in Stage 4 of the Demographic Transition Model, with both birth rate and death rate remaining low and the total population starting to level off.

Current trends affecting the UK's demographic profile:

• Impact of migration - Immigration has led to a slight increase in the country's birth rate and to its total population.
• Ageing population concerns - A large number of elderly people means that the death rate will probably increase slightly.
• Future uncertainty - The UK may transition to Stage 5, where the death rate becomes higher than the birth rate.