History, Issues, and Data Sets

9/10/06 updated 4/13/10


            1. History:  Between 1850 and 1900, the human population grew at an average rate of 1.0062 per year reaching 1.6 billion by 1900.  By 2000, the population growth rate had increased to 1.0143 and the population was 6.086 billion (World Population Growth.htm).  What happened?  We learned how to reduce death rates by using soap, clean water, and better nutrition.  The growth rate of any population is equal to its birth rate minus its death rate.  We reduced our death rate faster than we reduced our birth rate giving a higher net growth rate.  Our experience to date is that birth rates tend to decrease much slower than we can reduce death rates.  Birth rates have been reduced mainly through education and reduction of poverty (Decreasing Birth Rates.htm).  China reduced its birthrate from 43.8 births/1000 in 1955 to 16.2 by 2000 giving an average reduction of 0.6 births/1000/year.  The average birth rate in the world was 22.7 in 2000 which could be reduced to the death rate of 9.1 in about 23 years at the reduction rate achieved in China.  Even at a reduction rate half that achieved in China, 0.3 births/1000/year, the world could reach 9.1 births/1000 in about 45 years.  However, the rate of reduction in Africa was only 0.23/1000/year between 1955 and 2000.  There is obviously a need for incentives to reduce birth rates in rapidly growing countries.


            2. UN Millennium Project: The current UN Millennium Project (See Sacks, Foreign Affairs, March/April 2005.) proposes to reduce poverty and death rates even faster in poor countries.  If we reduce the death rates faster than the birth rates, we will increase the population explosion in those already over populated areas.  To succeed in the near term, the Millennium Project must reduce birth rates faster than death rates.  Economic growth is usually measured by looking at the GDP per capita which can be increased both by increasing the GDP and by reducing the population.  I suggest that we focus on reducing population growth to avoid making the population explosion worse in the near term.  Suppose the developed countries insist that continuing grants of foreign aid be tied to significant reductions in birth rates and slower reductions in death rates.  Education and economic independence of young women seem to be keys to reducing birth rates, but tying continuing foreign aid to reductions in birth rates and net growth rates will encourage cultures to develop effective means of reducing birth rates faster than death rates. 


            3. Human Cultures, Conflicts, and Migrations: The 61 most populous countries are grouped by dominant culture, or religion, in CIA cultures.htm.  The Muslim countries as a group have high birth rates and are trying to expand into western and southern Africa, southern Russia, and Southeast Asia.  These conflicts are already involving other cultures and are likely to expand.  After reading Huntington’s 1996 book, “Clash of Civilizations”, I think he was probably correct in saying that one culture should avoid becoming involved in the internal affairs of another culture.  However, each culture must control its own fanatics to minimize conflicts between cultures.  In the near future, conflicts between cultures are likely to increase because of Muslim and Jewish fanaticism. 


High birth rates in African, Hindu, Muslim, and Latin American countries are increasing pressure to immigrate into Europe and North America which is increasing opposition to immigration and building support for limiting welfare benefits in the receiving countries.  The developed countries need to link foreign aid, including food, to rapid reductions of birth rates in poor countries to slow increasingly massive migrations from poor to rich countries (CIA migration.htm).


            4. Economic Impact: Economists have generally favored population growth rates greater than zero because more consumers consume more goods and more workers reduce labor costs.  We should consider the transition to and effects of zero population growth on economic growth.  One indication of the probable effect on businesses is the expected reduction in the average growth rate of the S&P 500 index.  The S&P 500 index closed at 90.19 in 1975 and at 879.82 in 2002 giving an average growth rate of 1.0880, or 8.8%/yr compounded in spite of the bubble in 1995-2001.  The United Nations has estimated that the world population was 6.057 billion in 2000 and will likely reach 9.322 billion in 2050 giving an average growth rate of 1.00866, or 0.866%/yr.  Subtracting the population growth rate from the S&P growth rate gives (8.80 – 0.87) or 7.93%/yr.  However, economic growth is also dependent upon expectations.  If innovations produce growth of about 2%/yr and inflation averaged 3%/yr, a low estimate for growth of the S&P 500 might be 5%/yr.


            5. Environmental Impact: Human population growth is the main cause of most environmental problems.  The problems in the Middle East and Africa are essentially caused by human over population.  At the current rate of usage, the known reserves of oil will be exhausted in about 50 years (Fossil Fuel Reserves.htm) because too many people are using too much oil.  Significantly more oil may be found, but it is likely to be more expensive and to come from unstable countries.  The transition to new and alternative energy sources will be much easier if we control the size of the human population.  Human population growth is reducing the habitats for other animal species and plant species and causing extinctions.  Our numbers are causing the starvation, death, environmental pollution, and energy shortages we like to blame on technology.  In fact, only human population control, science, and technology can make it possible for us to make the transition to a lower, stable human population which could provide better food, water, energy, jobs, and education for all motivated individuals on earth.  Space is not the final frontier – we could never export enough individuals to make any difference in the earth’s population (Space.htm).  Earth with a smaller, stable human population is the only long-term solution.  


Primary Data Sets:

            1. UN population and GDP data:  The UN website tabulates detailed estimates for all countries and selected aggregates of countries by five-year intervals which is very useful for constructing plots of changes over time.  For example, I have used UN data to plot total human population growth and birth rates of specific countries and aggregates over time.  These data are only updated every five years.  The UN estimates Gross Domestic Products using official monetary exchange rates which tend to underestimate the real income of poor countries.


            2. CIA World Factbook: The United States Central Intelligence Agency maintains and updates a detailed public data base on all countries each year.  This is the most convenient online data base to use for more current information.  The CIA uses a market basket (Purchasing Power Parity, or PPP) approach to estimate GDP’s.  This data base does not include time series data and only aggregates data for the EU and the World.  The data set CIA_Data.htm was constructed from the CIA World Factbook online.  It includes all countries with populations of 15 million or more.  This sample includes over 90% of the world’s GDP and population.  It is amazing how much time and effort we spend on the affairs of a few smaller countries.


            3. US DOE, EIA data for energy consumption:  This online database was used to obtain specific and total energy consumption of the US and various countries in quadrillion Btu which was used with CIA GDP and population data to plot GDP generated versus energy consumed.


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