av Anthony Lombardi 6 år siden
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The birth rate declines to the point where it is close to the death rate. This causes the population to level off. Canada is approaching this point but has not yet reached it. A few countries, particularly in Eastern Europe have reached this stage.
Stage 3
A drop in Birth Rate occurs. Parents limit the size of their families because they are certain that their children will survive to adulthood.
Since most families live in cities rather than on farms, they don't need large numbers of children to perform farm chores. Family size decreases and women get the opportunity to work outside the home. Canada began to experience this stage in the early 1960's. The third stage has only just begun in many very poor countries
Stage 2
At some point the death rates drops (especially in infants) because better healthcare and nutrition and birth rate remain high - this result in a long period of natural increase in the population.
Canada's long period of natural increase began more than 150 years ago and continued through to the early 1960's. Look at figure 16.5 in the textbook to see Canada's stage 2.
In contrast to developed countries like Canada - stage 2 began only in the last 50 years or so. Decline in death rates combined with high birth rates resulted in rapid population growth in these countries.
Stage 1
The combination of a high birth rate and high death rate keeps the size of population stable. This pattern existed in Canada in the 17th and 18th centuries. There is no country in the world today in this stage.
At each stage of our lives, we play different roles. Demographers identify three important stages:
The assumption is that children and older adults do not work and must be supported by the working population. This is called the DEPENDENCY LOAD.
A Large dependency load puts lots of stress on society - education, housing, healthcare, senior's homes, and daycare.
Lets look at Figure 16-5 in our textbook:
Population Growth Rate = Natural Increase Rate + Net Migration Rate
= 3/1000 + 5/1000
= 8/1000
Net Migration Rate = Immigration Rate - Emigration Rate
= 7/1000 - 2/1000
= 5/1000
Natural Increase Rate =Birth Rate - Death Rate
= 10/1000 - 7/100
= 3/1000