Population Change

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EXPONENTIAL GROWTH

The worlds population has grown exponentially. This means that the rate of growth has beccome increasingly rapid. Between Ad1 and Ad1000 growth was very slow but in the last 1000 years it has had an dramatic increase. By 2000 there were 10 times as many people living as there had been 300 years ago. Not only is population increasing but the rate of increase is increasing.

population growth is usually shown as a line graph. Exponential growth produces a line that becomes steeper over time.

BIRTH RATE, DEATH RATE AND NATURAL INCREASE

Birth rate is the number of babies born alive per year per 1000 people. Birth rates vary between 5 per 1000 to 40 per 1000.

Death rate is the number of deaths per 1000 people per year. It usually lies between 5 per 1000 to 20 per 1000 unless there is famine, war or a epidemic in which the levels rise significantly.

Birth rates and death rates are expressed per 1000 so that figures for different countries of different sizes can be compared. Countries like china can be compared to countries like Luxembourg.

Natural change is the difference between birth rate and death rates in a country. It is a useful measure of a populations growth or decline and can use it explain populations statistics.

Data on birth rates, death rates and natural increase or decrease gives us information on the level of development of a country. whatever there stage of development all countries now have low death rates.

NATURAL CHANGE CALCULATIONS

BR- 10.7 per 1000 per year

DR- 10.1 per 1000 per year

NI- BR-DR

10.7-10.1

0.6

NI= 0.06%

How does population growth