Geography - Geography - Causes and rates of change
Geography - Causes and rates of change
Causes and rates of change
The population of any place changes over time. There are three main causes of population change:
* Births - usually measured using the birth rate (number of live births per 1000 of the population)
* Deaths - usually measured using the death rate (number of deaths per 1000 of the population)
* Migration - the movement of people in and out of an area
Rate of change
Births and deaths are natural causes of population change. The difference between the birth rate and the death rate of a country or place is called the natural increase, and you calculate the natural increase by subtracting the death rate per 1000 population from the birth rate per 1000 population:
natural increase = birth rate - death rate.
The rate of natural increase or growth rate of a population is given as a percentage, calculated by dividing the natural increase by 10.
If for example the birth rate / 1000 pop = 14, and the death rate / 1000 pop = 8, then