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Population Growth
Look at the growth in world population. COUNTER
Approx. every 2 seconds ten babies are born around the world. People die but overall every day there are approx. 200,000 extra mouths to feed.
What other things will be needed for these extra people?
Look at this graph.
You can see that the growth in world's population was fairly steady up until the mid 20th century and then it rapidly changed.
| Year reached | amount | years between |
| 1804 | 1 billion | |
| 1927 | 2 billion | 123 |
| 1960 | 3 billion | 33 |
| 1974 | 4 billion | 14 |
| 1987 | 5 billion | 13 |
| 1999 | 6 billion | 12 |
| 2013 | 7 billion | 14 |
| 2028 | 8 billion | 15 |
| 2054 | 9 billion | 26 |
As you can see the 'population explosion' is slowing down and it is possible that the population numbers may stabilise at around 10 billion.
You can clearly see the changes have been most dramatic in the less developed regions. MAP
So what are parts of this population change?
There are really three component, birth rate, death rate and migration
Birth rate: the number of births per thousand population per year. This varies but in rich industrial countries it is about 12-13 per 1000 whereas in poorer developing countries it is about 26-27 per 1000 TABLE OF BR. It seems that the more developed the country is, the lower the birth rate. PLOT GRAPH OF hdi V br
Generally speaking the countries with the lowest birth rate are in Europe whereas those with the highest are in Africa and the Middle East . WHY?
| High birth rates in Africa and the Middle East | |
| Political |
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| Economic |
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| Social |
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| Low birth rates in Europe | |
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Death Rate: the number of deaths per thousand population per year This tends to be similar throughout the world, with an average at about 10 per thousand. DATA OF DR. Death rates fell dramatically in the second half of the 20th century due to the spread of medical knowledge, and improvements in primary and secondary health care, (What also changed at this time?) Primary care is preventing disease, secondary is treatment. Few countries now have a death rate above 20 per thousand. Coupled to this is the fact that a large percentage of the population is below 15 and so reduces the chance of death. Most are in southern Africa where HIV/Aids has taken a serious toll on life.
Linked to death rate is life expectancy (Look here at how life expectancy has changed over the years). and it is the southern African countries that are witnessing a falling life expectancy.
Natural increase: this is birth rate minus death rate, usually expressed as a percentage. Poor counties tend to have a low DR and a high BR and so have a high natural increase, whereas rich counties have a low BR and a DR so have a low increase. Indeed some have a BR lower that their DR and so have a natural decrease.
Net Migration: People move in (immigration) and out (emigration) of a country and this obviously will have an impact on the population growth of the country. The rates are expressed per 1000 of population.
If a country had a BR of 10.3 and a DR of 8.3 then it's natural increase is 2 . If the migration rate is +2.0 then the population change per thousand of population each year is 4.0