Unit 8: Population - Population structure

Population structure

Source: http://www.slideshare.net/PLANETGE0GRAPHY/population-structures-10191768

Source: http://www.slideshare.net/kingcobra2012/ib-ess-topic-3-human-population

The Dependency Ratio

The dependency ratio shows how reliant young and old people are on the economically active population. A higher dependency ration indicates that more of the population is reliant on the working population. The ratio and can be expressed as follows:

Dependency Ratio = Young Population (0 - 14) + Old Population (65+) / Population Aged 15-64

The Support Ratio

The support ratio is the inverse of the dependency ratio:

Support Ratio = Population (15 - 64) / Population (65+) + Population (0 - 14)

Juvenile Index

The juvenile index indicates the proportion of young people to old people. The greater the index, the more young people there are.

Juvenile Index = Population (0 - 14) / Population (15+)

Old Age Index

The old age index indicates the proportion of old people to young people. The higher the old age ratio the greater the number of old people.

Old Age Index = Population (65+) / Population (15-64)

Source: https://geographyas.info/population/population-structure/

The demographic transition model 

Source: http://geographyfieldwork.com/DemographicTransition.htm

Source: http://www.medicine.uottawa.ca/sim/data/Demographic_Transition_e.htm