What is a population pyramid?
A population pyramid is a graphical illustration that shows the distribution of various age groups in a population (typically that of a country or region of the world), which forms the shape of a pyramid when the population is growing. (from Wikipedia, the free encyclopedia)
Match the key terms with their definitions.
Birth rate: the number of births, per year, per 1000 people in the population.
Death rate: the number of deaths, per year, per 1000 people in the population.
Life expectancy: average number of years a person at birth can expect to live.
Declining: to become smaller, weaker, or less important.
Middle age: subjectively: 40 – 64 years old.
Older age: subjectively: 65 + years old.
Dependency ratio: the ratio between those in the non- economically active age group (taken to be children under 15 and adults over 65) and those in the economically active age group (15 to 64).
Concave: curving inwards.
Convex: curving outwards.
Population pyramid: a graphic method of illustrating the age and sex structure of a population.
Describe the population pyramid for Niger.
The 2010 population pyramid for Niger is expansive, and it is in the perfect shape of a pyramid. It clearly shows that Niger has a high birth rate and low life expectancy because there are many newborns and young children but very few older aged people. The pyramid also has concave sides, and for each upward age group, there is a drop in population because of high death rate. The pyramid shows the same change in shape for males and females. This is a good representation of how underdeveloped Niger is.
Describe the population pyramid for Saudi Arabia.
The 2010 population pyramid for Saudi Arabia is stationary. It has convex sides, and there is no huge drop in population for each upward age group, which means there is a longer life expectancy. Although the birth rate is not extremely low, the pyramid shows how it is declining – there are more middle aged people than newborns (especially on the male side). These are all signs that Saudi Arabia is becoming more developed.
Decide which stage the following 12 population pyramids are in: