Income and Population Growth:
GNP: total value of all materials, foodstuffs, goods, and services produced by the companies of a country in a particular year. GNP measures the nationality of production so an American Ford Motor Company auto-assembly plant in Mexico contributes to the American GNP.
GDP: Gross Domestic Productan estimate of the total value of all materials, foodstuffs, goods, and services produced withing the borders of a country in a particular year. GDP measures what is produced within the borders of a country regardless of ownership. In this case, the American Ford Motor Company auto-assembly plant in Mexico contributes to the Mexican GDP.
How do people enter and leave a given population?
Births and Deaths
Total fertility rate (TFR) is the average number of children a woman will have between 15-49 years old.
Births - deaths = natural increase
Doubling Time: while a 4% rate of natural increase may appear small at 2% per year,
Use the "rule of 72" for calculating doubling time
from the rate of natural increase.
Divide 72 by the rate of natural increase to get the number of years it will take for a given population to double. For example, if you want to know how long it will take to double a given population at a four percent rate of natural increase, divide 4 into 72 and get 18 years.
Discussion: How is population growth related to income?