Key Issue 2: Where has the World's Population Increased?

Main Ideas:
Natural Increase -Geographers most frequently measure population change in a country or the world as a whole, through the measures of:

• Crude Birth Rate (CBR)- the total number of live births in a year for every 1,000 people alive in the society. A CBR of 20 could be interpreted as for every 1,000 people in a country, 20 babies are born over a one year time span.
• Crude Death Rate (CDR)- the total number of deaths in a year for every 1,000 people alive in the society. Comparable to the CBR, the CDR is expressed as th annual number of deaths per 1,000 population.
• Natural Increase Rate (NIR)- the percentage by which a population grows in year. It is computed by subtracting CDR from CBR, after first converting the two measures from numbers to percentages. So, if the CBR is 20 and the CDR is 5, the NIR would by one and half percent.   

Approximately 80 million people are added to the world population each year. As the world continues to develop, nearly 100% of the world's natural increase rate comes from less developed countries who remain uneducated on methods of contraception and have few women in the workforce. 
Doubling time is the number of years needed to double the population, assuming a constant rate of natural increase. The graph below displays the global Natural Increase Rate in relation to the global crude birth rates and death rates.

Fertility -  Geographers also use the total fertility rate (TFR) to measure the number of births in a society. This is the average number of children a women will have throughout her childbearing years, which typically range from the ages of 15 to 49. The TFR for the world is 2.7. Less developed countries tend to have higher total fertility rates than more developed countries for the same reason that their natural increase rate is higher, women are not present in the workforce and are uneducated in methods of contraception.

Mortality - Mortality primarily refers to the crude death rate (CDR) or the number of deaths per 1,000 people in a country. Another principle of mortality is the infant mortality rate (IMR) which is the annual number of deaths  in infants under 1 year of age in comparison to total live births. 
The chart below displays countries in ascending order of infant mortality rates.

Details:

The following video explains causes of infant mortality rates and means of prevention, primarily in the United States, which actually has a higher infant mortality rate than the majority of other developed countries.
Reducing Infant Mortality


The article below expands on an unlikely life expectancy rate comparison to Spaniards and other citizens of European union countries.

Spaniards Live Longer Than EU Average, But with Worse Health