Demographyis the scientific study of
population growth and change. Everything in society
influences demography and demography conversely influences
everything in society. After World War II, the United States began
to recover from the long-term negative effects of the war. Families
had been separated, relatives died or were injured, and women who
had gone to the factories then returned home at war's end. For
about 4 years goods and services were rationed and the government
had assumed war-time powers which they thought limited the civil
rights of the average citizen. It was an era of social and cultural
upheaval.
The year 1946 reflected the impact of that upheaval in its very
atypical demographic statistics. Starting in 1946 people married
younger, had more children per woman, divorced then remarried
again, and kept having one child after another. From 1946 to 1956
the birth rate rose and peaked, then began to decline again. By
1964 the national high birth rate was finally back to the level it
was at in 1946. All those millions of children born from 1946-1964
were called the Baby Boom Generation (there are about 78 million of
them alive today, see Chapter 12). Why was there such a change in
family-related rates? The millions of deaths caused by the war, the
long-term separation of family members from one another, and the
deep shifts toward conservative values all contributed. The Baby
Boom had landed. And after the Baby Boom Generation was in place,
it conversely affected personal and larger social levels of society
in every conceivable way.
The Formula
In this chapter you will learn how financial, educational,
spiritual, cultural, and emotional social forces shape and form the
demographic trends within a society. You'll also get a glimpse of
how demographic forces shape your society. The core of demographic
studies has three component concerns: births, deaths, and
migration. All of demography can be reduced to this very simple
formula:
This part of the formula, (Births-Deaths) is called
Natural increase, or all births minus all the deaths in a
given population over a given time period. The other part
of the formula, ((In-Migration)-(Out Migration)) is called
Net Migration which is all the in-migration minus all the
out-migration in a given population over a given time
period. Population Change is then added to a previous
year's population to yield new population estimate. Most official
population counts really are estimates. There are mistakes in
counting that render results that are close, but never perfectly
accurate.
Let's consider this formula by first looking at the US
population in 1990. Census Enumeration is the
formal counting of a population by its government. Based on the US
Census, the US population was 248,709,000 (retrieved 7 April, 2009
from http://www.census.gov/main/www/cen1990.html
). If you start the estimate with the 1990 population, you can run
the numbers through the formula and derive an end of year 1999
population estimate. You can see the results of adding all the US
birth, death, and migration data for 1990-1999 in Table 1
below.
Table 1. Numbers of Births, Deaths, and Net Migrationa for the
United States between 1990-1999b
Births
- Deaths
+ Net Migration
= Population Change
39,860,000
22,711,000
9,580,000
+26,729,000
a Net Migration=(In-Migration)-(Out-Migration) or
(9,800,000)-(220,000)=(9,580,000)
b Data collected from two sources retrieved 7 April, 2009: Martin,
P. & Midgley, E. (2003) "Immigration: Shaping and Reshaping
America," Vol. 58, No. 2 Population Bulletin from www.prb.org; and
www.census.gov Table 77. Live Births, Deaths, Marriages, and
Divorces: 1960-2006.
By the end of 1999 the population was estimated to be
(1990)+(1990-1999 population change)=1999 population or
(248,709,000)+(26,729,000)=275,438,000. These estimates are very
close to the actual July 1st, 1999 US Census estimates (retrieved 7
April, 2009 from http://www.michigan.gov/documents/90...eg_26029_7.pdf
US POPULATION 1790-2000).
Table 2 lists the 10 most populated countries of the world in
2008 and the US ranks 3rd in 2008. The US is one of the most
populated nations of the world and is estimated to continue to rank
3rd even in 2050. Interestingly, in 2050, India will rank 1st and
China 2nd (see Table 3 for the details).
Table 2. The Ten Most Populated Countries in the World,
2008*
Figure 1 shows the US population for selected years between 1790
(the 1st US Census) and 2009 (estimated by the US Census Bureau).
At its first official Census, the US had more than 4 million
inhabitants, but it failed to count Natives, Blacks, and other
racial groups. In the 219 years represented in Figure 1, you can
see that the US population has increased nearly 78 times since its
1790 count-this taking into consideration all the births, all the
deaths, and all the in-out migration. The US continues to grow in
our day and will in coming years.
Figure 1. Estimated Population of the United States for Selected
Years 1790-2009*
*Retrieved 9 April, 2009 from Table 1: Population Bulletin, Vol.
57, No 4 What Drives US Population Growth? Dec, 2002 http://www.prb.org/Source/57.4WhatDr...Population.pdf;
Statistical Abstracts of the US, 1997 Table 1; 2009 estimated
retrieved from www.census.gov
Let's look at the birth rates for the US compared to the current
highest birth rate state, Utah, and the current lowest birth rate
state, Vermont, between the years 1991-2006. But, first we need to
define rates. The Crude Birth Rateis the
number of live births per 1,000 people living in the
population. It's called crude because it ignores
age-specific risks of getting pregnant. Figure 2 shows these rates
and clearly indicates the higher rates for Utah in comparison to
the US and Vermont. Before 1991, Alaska often competed with Utah
for the highest state birth rate. Vermont is the lowest state rate
today, but has also competed with Maine in past years.
Figure 2. Estimated Crude Birth Rates per 1,000 Population of
the United States, Utah, and Vermont for Selected Years
1991-2006*
*Retrieved 9 April, 2009 from Table 77 Live Births, Deaths,
Marriages, and Divorces: 1960-2006; Statistical Abstracts of the US
and 1990-2006 from 1990-2006 data retrieved 9 April, 2009 from
205.207.175.93/VitalStats/Tab...tableView.aspx
There are other rates to measure births between populations.
Demographers use slightly different terminology than the average
person when describing a woman's ability to get pregnant.
True Rate is the "Number of events/
Number" at risk of the event. In other words, the Crude
Birth Rate is not a true rate because it includes children, males
and the elderly in the denominator of "1,000 population." To
demographers, Fertilityis a measure of
the number of children born to a woman.
Total Fertility Rateis the total
number of children ever born to a woman calculated both
individually and at the societal level.
Fecundityis the physiological ability to
conceive or give birth to children. In Table 4 you can see
some of the striking differences in Crude Birth and Total Fertility
Rates. To understand these data you need to understand the term,
More Developed Nations are nations with comparably higher
wealth than most countries of the world including: Western Europe;
Canada, United States, Japan, New Zealand, and Australia.
Less Developed Nations are nations located near to or south
of the Equator which have less wealth and more of the world's
population of inhabitants including: Africa, India, Central and
South America, most island nations, and most of Asia (Excluding
China). China has the most strict fertility policy in the
world and is often excluded from the rest of Asia in most official
reports.
Table 4. Crude Birth Rates and Total Fertility Rates for
Selected Regions and Countries*
Country or Region
Crude Birth Rates CBR
Total Fertility Rates TFR
More developed
12
1.6
Less Developed
23
2.8
Africa
37
4.9
Latin America/Caribbean
21
2.5
Asia (Excluding China)
23
2.4
China
12
1.6
Liberia
50
6.8
Canada
11
1.6
Mexico
20
2.3
United States
14
2.1
Italy
9
1.3
Japan
9
1.0
World
21
2.6
*From 2008 World Population Data Sheet: Demographic Data and
Estimates for the Countries and Regions of the World.
Africa is the "birth hot spot" of the world and has been since
about 1950. It has a projected population change of an increase of
100 percent between the years 2008-2050. A few African nations are
higher and some are a bit lower. Uganda for example should
experience a 263 percent increase while Swaziland should experience
a 33 percent decline. The 6.8 TFR for Liberia means that the
average woman is expected to have 6.8 children there. In the US it
is only 2.1. This is an important indicator of population change
because there is a principle which states that it requires a
minimum TFR of 2.1 for the population to replace the man and woman
who made the children and a TFR of 2.3 to begin to expand the
population. Thus you can see from Table 4 that the less-developed
regions of the world (especially Africa) are expected to grow,
while the more developed (especially Japan) should not grow. Japan
should decrease by 25 percent between 2008-2050.
Theories and Principles
Doubling Timeis the time required for
a population to double if the current growth rate
continues. To calculate the doubling time you simply
divide 70 by the current growth rate of the country and that yields
the number of years required for the double. Table 5 shows the
growth rates and estimated doubling times for selected countries
based on 2008 estimates. The world's population should double in 58
years. Liberia on the other hand should double its population in
only 23 years.
In fact, most of the world's population now lives in the less
developed regions of the world and they will double in about 47
years. There are approximately 68 percent of the 6.7 billion
peoples of this world who now live in less developed countries
(roughly 4.56 billion people). In the year 2055 (the year 2008 + 47
years=2055) there should be 9.12 billion people living in the less
developed regions of the world. The more developed regions of the
world will not double in any of our lifetimes (it would be the year
2358 according to these data).
Zero Population Growthoccurs when a
population neither shrinks nor expands from year to year. Based on
other factors in the demographic equation, including death and
migration, you can see various results. To understand why
some countries have higher or lower rates, you must first
understand some theoretical backgrounds.
There are two distinct perspectives that relate to births in a
population. Antinatalistis a perspective
which opposes childbearing and Pronatalist is a perspective which
promotes birth and increased population. Antinatalists
oppose birth, support contraceptive, abortions, and sterilization
along with the education of women. Educating a woman is the most
effective way of lowering her fertility. Pronatalists support
birth, large families, extended families, and the governmental
support of childbearing.
Table 5. Growth Rates and Doubling Times for Selected Countries
2008*
Country or Region
Growth Rate
Doubling Time in Years
More developed
0.2
350
Less Developed
1.5
47
Africa
2.4
29
Latin America/Caribbean
1.5
47
Asia (Excluding China)
1.5
47
China
0.5
140
Liberia
3.1
23
Canada
0.3
233
Mexico
1.6
44
United States
0.6
116
Italy
0.0
Can't Calculate
Japan
0.0
Can't Calculate
World
1.2
58
*From 2008 World Population Data Sheet: Demographic Data and
Estimates for the Countries and Regions of the World.
The US had an antinatalist perspective until then President
Ronald Reagan changed the US foreign policy in the 1984 population
conference held in Mexico City. President Bill Clinton eventually
changed it back to antinatalist. George W. Bush changed it back to
pronatalist and President Barack Obama changed it back to
antinatalist again. Once a US President chooses the nation's
perspective, international and local policies come into effect by
supporting pro-or antinatalist programs.
The first Antinatalist was Thomas Malthus (1766-1834). He was a
Reverend and English scholar who took a strong stance against the
unprepared parents of his day. To him "prepared parents" had
established their education and livelihood, their household, and
their marriage before they considered getting pregnant. Keep in
mind that there were very few effective methods of birth control at
this time, so Malthus came across as a hardliner against parenting.
He published half a dozen editions of his work, An Essay on the
Principles of Population (1798-1830) which were extremely
controversial, yet carefully read by many influential people of his
day.
For Malthus the problem was that populations grew more rapidly
than the production of food, which to him was the cause of many
social ills in the new industrial societies of Europe. See Figure 3
for a graph depicting the shortage. He declared that no sex before
marriage, forced sterilization, and criminal treatment of
unprepared parents would be the new conservative norm.
Indeed history has shown that famines, wars, plagues, and other
terrible conditions do occur. The antinatalists blame too many
babies and people, too much destruction of the natural environment,
the existence of the traditional family, and capitalistic
profit-seeking at the cost of global well-being. A contemporary
antinatalist named Paul Ehrlich wrote the book, The Population Bomb
in 1968 (Ballantine Books). He is considered to be a
Neo-Malthusian, or an antinatalist who
agrees with Malthus, but rejects his conservative and religious
proscriptions. Much of the governmental organizations in
the world today are antinatalistic.
Figure 3. The Malthus Graph Depicting the Shortage That Occurs
When Population Growth Exceeds Food Production Capacity.
The pronatalists point out that there is plenty of food in the
world and always has been. They blame political and social
mismanagement for the social ills, not the high birth rates. Look
at Figure 4 below to see the estimated world population from 10,000
BC to 2009 AD (these are only estimated since there were very few
government statistics prior to the industrial revolution).
You can clearly see that there were millions and millions of
people on the earth throughout the history of the world.
Pronatalists argue that for the most part, civilizations ate,
lived, and thrived and still do today. When they starved it was
typically some political or natural disaster factor not a
Malthusian shortage that explained it. Besides, they argue, Malthus
underestimated the enormous gains in medical, agricultural,
environmental, political, and other sciences that have given this
world the highest standard of living it has ever known. Do you feel
a bit confused? Truth is that there is ample evidence to support
both antinatalist's and pronatalist's perspectives. Bottom line is
that the World Health Organization, World Bank, United Nations,
United States, and all of the other more developed nations of the
world are Neo-Malthusian/Antinatalistic to some degree or another.
While the people of the less developed regions of the world live a
pronatalist's lifestyle and thereby are mainly responsible for the
rapidly increasing growth of births into the world population.
Figure 4. World Population Estimates in Millions for 10,000 BC
to 2009 AD*
*Retrieved 9 April 2009 from US Census Bureau 's Historical
estimates of the World's Population (10,000 BC to 1950 AD)
www.census.gov/ipc/www/worldhis.html and from Historical World
Population Estimates From Year 0 to 2050 How many people have ever
lived on Earth? www.prb.org/Journalists/FAQ/W...opulation.aspx
Look at Table 6 below to see how fast the US and World are
growing by seconds, minutes, hours, etc. In the US, every hour 432
babies are born, totaling up to about 3,784,320 in a year (please
note that this estimate tends to be lower than the actual number
reported by the US's Vital Statistics at 4.2 million births,
because estimates are calculate base on previous years' rates,
whereas the Vital Statistics are actual counts made 2 years after
the actual data has been collected and tabulated.
In the world, every hour 15,834 babies are born adding up to
138,715,000 per year. Wow, that's just a great deal of babies! How
do you suppose anti- and pronatalists might respond to these data?
You're probably right, in totally opposite camps.
Table 6: United States and World Population Clocks 2009*
Births Per:
United States
World
Second
0.12
4.40
Minute
7.20
264.00
Hour
432.00
15,835.00
Day
10,368.00
380,041.00
Year
3,784,320.00
138,715,000.00
Deaths Per:
United States
World
Second
0.08
1.80
Minute
4.80
108.00
Hour
288.00
6,481.00
Day
6,912.00
155,553.00
Year
2,522,880.00
56,777,000.00
*Retrieved 9 April, 2009 from www.census.gov/population/www/popclockus.html
and from www.prb.org/Articles/2008/wor...clock2008.aspx
Look at the deaths in table 6. Think about it. If you can hold
your breath for 30 seconds, about 2 people will die in the US and
over 54 will die worldwide during that time. Death
is the termination of the body, its systems, and brain activity in
an irreversible way. Death is a part of life. All of us are at risk
of dying, but not all of us share the same risks. To be born around
or below the equator, female, tribal, and non-white represents risk
factors not shared by those born in the US, female, suburban, and
non-white (think about Max Weber's Life Chances). In fact, in many
cases migrants to the US raise their life expectancies higher than
they would have been back in their less developed home
countries.
Figure 5 shows the top 10 causes of death in the US. Heart
disease is and has been the number 1 killer in the US for decades.
Heart disease has lead world-wide causes of death for decades as
well. The top 4 causes are highly correlated with tobacco use. And
since smoking is becoming much more common in less developed
countries, cancer is predicted to become the number 1 cause of
death world-wide by 2010 with over 40 percent of the world's
smokers living in China and India (retrieved 10 April, 2009 from
www.foxnews.com/story/0,2933,464184,00.html).
In less developed nations there are other significant causes of
death that we don't worry about here as much. Malaria, AIDS,
accidents, maternal death, diarrhea, Measles, Mumps, Rubella, local
exotic diseases, and other infectious and parasitic diseases. In
fact, AIDS or Acquired Immune Deficiency Syndrome is much more
common in Africa and parts of Asia than in any other region of the
world. Heterosexualityis sex between a
man and woman and is the most common way of transmitting AIDS
throughout the world. Scientists from many different
disciplines study and track diseases such as AIDS and the
others.
Epidemiologyis the scientific study of
diseases, their transmission, and their management. The US
has the most advanced disease tracking and epidemiological
management system which is found at the Center for Disease Control,
Atlanta, Georgia (http://www.cdc.gov/ ). On this
website you can click on "Traveler's Alerts" and choose a country
to see if there are any disease concerns for tourists
(wwwn.cdc.gov/travel/default.aspx ). Go to the website, pick a
country and read up about their current disease concerns and shots
you should get in preparation to visit another country.
Figure 5. Top 10 Major Causes of Death in the United States
2005*
Because we have so many visiting and migrating to and from the
US, it is in the CDC's best interest to be globally concerned and
involved. The CDC concerns itself with all diseases in every
country. Demographers also concern themselves with a number of
death-related rates. The Crude Death Rate is the number of
deaths in a given population per 1,000 people living in that
population. Again, this is not a true rate because not all
members of society have the same risks of dying (IE: 30 year-olds
not at the same risks of death as 80 year-olds). The Infant
Mortality Rateis the number of infant deaths per
1,000 live births. The CDR and IMR vary greatly between
countries and regions (See Table 7 below).
The nation with the worst Crude Death Rate is Sierra Leone at
23. The best CDR's are found in the Middle East (Qatar and the
United Arab Emirates at 2). The nations with the worst IMR happen
to be Afghanistan at 163 and Sierra Leone at 158. The best IMR is
found in Iceland at 1.3. The US does not have the best IMR. This is
most likely a consequence of not having universal medical care.
Table 7 shows some of the variations in death rates for select
regions and countries. To summarize these and other findings in
this chapter you can conclude that: 1) more babies are born in
developing nations of the world than in the developed ones; 2) more
infants and other people die sooner in the less developed regions
of the world than in the developed ones; and 3) most of the world's
future population growth will come from the less developed regions
of the world.
Table 7. Crude Death Rates and Infant Mortality Rates for
Selected Regions and Countries*
Country or Region
Crude Death Rate CDR
Infant Mortality Rates TFR
More developed
10
6.0
Less Developed
8
54.0
Africa
14
82.0
Latin America/Caribbean
6
23.0
Asia (Excluding China)
7
45.0
China
7
23.0
Liberia
18
133.0
Canada
7
5.5
Mexico
5
19.0
United States
14
2.1
Italy
10
4.2
Japan
9
2.8
World
8
49
*From 2008 World Population data Sheet: Demographic Data and
Estimates for the Countries and Regions of the World.
Why is the world's population growing so rapidly in regions that
have the fewest resources? Part of the answer to this question is
found in the Demographic Transition Theory which claims
that populations go through 3 distinct stages that correspond to
the onset of the Industrial Revolution with regard to changes in
birth and death rates. Look at Figure 6 below to see the
three stages of this theory.
As you can see, the Demographic Transition Theory has three
distinct stages. Stage 1, the Pre-Industrial Revolution Stage,
encompassed the world's population up until about 1700 AD. Much of
the world's population grew very slowly up to that point. That's
all it could do because the high birth rates were offset by the
high death rates (lots of people were born and they died soon).
Stage 2 or the Industrial Revolution Stage saw the decline in
death rates while birth rates remained high. This is the perfect
demographic storm for population growth and this coincides with the
rapid growth of populations in Western Civilizations (lots of
people were born and they died later in life). The Post-Industrial
Revolution, Stage 3 came with the technical and computer chip
revolution that raised the standard of living so much that death
rates remained low while birth rates dropped (fewer people being
born and they die even later in life).
The Demographic Transition theory did describe what happened in
Western Europe, Canada, The United States, Australia , and Japan.
But, it does not fit so neatly in the less developed countries of
the world. They never really had an Industrial Revolution, they
only benefited from the European one. They never really moved fully
into the technological and computer chip revolution. It just spills
over to them gradually. Because of post World War II medical
delivery systems and because of international aid, the less
developed countries of the world have had their death rates decline
and their lives have been extended. But, their birth rates remain
relatively high (as you've already read above). This is why so much
of the world's future population growth will come from Africa,
Latin America, Parts of Asia, and the island nations.
Very concerted antinatalistic efforts have been implemented in
the less developed countries of the world over the last 40 years.
Scientists can measure a gradual lowering of the birth rates as a
direct result from it. But, keep in mind that however they got
there, the peoples of the less developed regions of the world are
still in Stage 2 and have explosive population trends that will
continue for the next 40-50 years.
Population Structures
Before we discuss migration, let's talk about the population
from an age-sex structural point of view. Every population/society
can be compared by an age-sex structural approach called the
Population Pyramid, or the graphic
representation of specified 5-year age groups within a population
and by being males or females. Look at the 1990 US
population pyramid in Figure 7 below. Please notice that this
pyramid was available on a quick search of www.census.gov and
represents blue for males and green for females.
A population pyramid for 1990 can tell you some interesting
things about the age-sex structure of the US at that time. For one
thing, even though there are slightly more females than males,
their relative proportions appear about even here. It also shows
you the bulge of the Baby Boomers. By 1990, the Baby Boomers would
have been between ages 26-44. The high fertility rates of the years
1946-1964 echo in the bulge of this pyramid. Also there is an
interesting sex differences among the older US population. There
are far more females than males in the later years.
Now look at Figure 8. It shows you smaller pyramids that let you
watch the disappearance of the Baby Boomers gradually over the
years 1990-2050. By the year 2050 the oldest Baby Boomer would have
to be 104 years old to still be alive. The Youngest Baby Boomer
would be 86. These pyramids also show that there will be a similar
proportion of males and females. Because birth rates are low and
are remaining that way, you see a widening look as the pyramid
portrays the population more as a column than a pyramid. Population
pyramids can actually take on any number of shapes. But the true
pyramid shape comes only when there are high birth rates (a wider
pyramid in the younger ages) and people die soon (a narrower
pyramid in the older years at the top of the pyramid).
Figure 7. United State's Population Pyramid: 1990*
*Retrieved 10 April 2009 from
www.census.gov/population/www.../natchart.html
Figure 8. United State's Population Pyramid: 1990, 2000, 2025,
and 2050*
*Retrieved 10 April 2009 from
www.census.gov/population/www.../natchart.html
As this chapter draws to a close, we must discuss the last
portion of the demographic formula, Migration. If someone moves out
of your country they are called emigrants.
Emigrationis the departure from your
country of origin to reside in another. Once there, they'd
be considered to be an immigrant. Immigrationis the arrival of a foreigner into a country they will
reside in and likely become a citizen of on some future
date. The US has far more immigrants (arrivals) than
emigrants (departures) every year.
Why do people decide to move from one country to another?
Demographers consider two very important factors in understanding
migration: push and pull. Push Factorsare
negatives aspects of where you live which make you consider
leaving. Pull Factorsare
positive aspects of another place which draw you to migrate to
it. Push factors include wars, famines, political
hostility, natural disasters, and other harsh circumstances that
create an environment conducive to looking for another place to
live. Pull factors include economic prosperity, jobs, food, safety,
asylum, and the hope of survival that draws people to move to the
desired location. About 1 in 6 people in the US moves each year.
College students, job seekers, transferees, divorcees, and most
recently people needing to live with extended family because of
tough economic times all contribute to the migration process within
the United States. As we finish the demography chapter, keep in
mind that demography effects everything and everything effects
demography
