Population Pyramids Global Geography 12

Population Pyramids A graph that shows the age-sex composition of a population.

Cohorts A specific portion of the population that is combined together in an age group for the purposes of simplifying a population pyramid. Five-year cohorts are commonly used in population pyramids.

2 Types of Population Pyramids 1) Expansive: An age-sex structure with a wide base and narrower top. This indicates a high birth rate and an expanding population. 2) Stationary: An age-sex structure that indicates no or very little population growth. The pyramid is characterized by relatively straight sides.

What can we learn from Population Pyramids? Economic Dependants Baby Booms Population Growth or Decline Gender Imbalance

What happens next?

What is going to happen to Japan’s population in the future?

Demographic Transition Model

Demographic Transition Model The DTM describes a sequence of changes in the relationships between births and death rates. It suggests that the population growth rates for all countries can be divided into 5 stages.

Stage 1 – High Stationary Birth Rate – Very High Death Rate – Very High Natural Increase – Population is steady Example: No countries are currently in this stage. Isolated Brazilian tribes are often used an example.

Stage 2 – Early Expanding Birth Rate – Very High Death Rate – Falling Rapidly Natural Increase – Very Rapid Increase Example: Egypt, Kenya, India

Stage 3 – Late Expanding Birth Rate – Falling rapidly Death Rate – Falling more slowly Natural Increase – Rapid increase Example: Brazil

Stage 4 – Low Stationary Birth Rate: Falling more slowly Death Rate: Slight fall Natural Increase: Very slow increase Example: USA, Japan, France, UK

Stage 5 - Declining Birth Rate: Slight fall Death Rate: Stable Natural Increase: Gentle decrease Example: Germany (in the future)