Birth Rate is the term used to define the number of babies born every year per 1000 people in a population.
Death Rate is the term used to define the number of deaths every year per 1000 people in a population.
Natural increase in a population occurs where Birth rate is greater than death rate. That is, that there are more births than deaths in that population ion a year.
Natural decrease occurs when death rate is greater than birth rate. This means that more deaths occur in a population than babies are born so population numbers decline.
How is the natural increase found?
Natural Increase (per cent) =
Birth rate – death rate
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| Death rate is higher than birth rate = Smaller Population or a natural decrease in the population | If birth rate is higher than death rate = Larger Population or a Natural increase in the population size |
LEDC’S are more likely to have a higher death rate than MEDC’S due to illnesses and lack of medical treatment.
Of course, this balance is changed by Migration. If people move into a country (Immigrants) the population will increase. If people leave a country (emigrate) the population could decrease.
Activities
1) Take a bytesize test bite on this topic after reading their revision notes
2a) Draw line graphs of the birth and death rate data on this excel file.
b) Describe and explain how the birth and death rates for those countries change.
3a) Calculate the natural increase for the following countries
| Country | Birth Rate | Death Rate | Natural Increase |
| Mauritius (2007) | 15.3 | 6.9 | |
| Mauritius (1970) | 25.1 | 8.1 | |
| UK (2007) | 10.7 | 10.1 | |
| UK (1970) | 12.5 | 11.9 |
