UN Population Division, Department of Economic and Social Affairs,
with support from the UN Population Fund (UNFPA)

95-02: Population Today, February 1995


The electronic version of this journal is being made available by

the Population Information Network (POPIN) Gopher of the United

Nations Population Division, Department for Economic and Social

Information and Policy Analysis, in collaboration with the

Population Reference Bureau and with funding from the Andrew W.

Mellon Foundation.


                        Population Today

                         February 1995 

Please note: The graphics that appeared in the printed copy of

Population Today have not been included here. For a complete copy

of Population Today, send $2.00 to Population Reference Bureau,

1875 Connecticut Ave., NW, Suite 520, Washington, D.C. 20009.

Homicide in the United States: Who's at Risk?

By Machiko Yanagishita

Nearly 70 people die each day in the United States as the result

of a homicide--about 25,500 deaths per year.  Public opinion polls

show that Americans rank crime, particularly violent crime, at or

near the top of their concerns.  News reports of drive-by

shootings, children killing children, or joggers assaulted raise

concerns about the prevalence of homicide.  But how realistic is

this image, and who is most at risk of becoming a homicide victim? 

A just-released report from PRB, Homicide in the United States:

Who's at Risk? takes a closer look.

The United States has an extraordinarily high homicide rate.  In

1992, there were 10.0 homicides per 100,000 people,  a much higher

rate than all other industrialized countries, where homicide rates

range from less than 1.0 to about 7.5 per 100,000 people. During

the early 1990s, the U.S. rate was 17 times that of Japan, and 10

times that of both Germany and France.  These countries have

homicide rates among the world's lowest, according to the United

Nations' 1992 Demographic Yearbook.

The U.S. homicide rate has fluctuated considerably during the

past half century. In 1933, when all states began reporting data

to a national registry, the homicide rate was 9.8 per 100,000. 

The national rate began a steady decline until the late 1950s,

except for a brief spike after World War II.  Then the homicide

rate began to climb, from 4.7 in 1960 to a new high of 10.1 per

100,000 in the mid-1970s. Throughout the 1970s and 1980s, homicide

alternated between periods of decline and increase.  It hit an

all-time high of 10.7 in 1980, then dropped to 8.4 in 1984.  Since

the mid-1980s, the homicide rate has risen and remains high.

Homicide rates have risen sharply among teenagers (ages 15 to

19) in recent years for both African Americans and whites, males

and females. The jump was particularly sharp for African-American

teenage boys (ages 15 to 19)--almost tripling from 46.7 to 134.6

homicide victims per 100,000 between 1985 and 1991.     

Homicide victims, as well as offenders, are strikingly

concentrated among teens and young adults. In 1991, the highest

rates were for ages 20 to 24. In this age group,184 per 100,000

black men died of homicide. The rates in this age group are 27 per

100,000 for black women, 19 per 100,000 for white men, and 5 per

100,000 for white women.   

The wider group of young people ages 15 to 29, who make up only

about one-fifth of the U.S. population, account for about half (48

percent) of victims and two-thirds of offenders. Some observers

have speculated that the entrance of the large post-World War II

baby-boom generation into the young adult years was responsible

for the increase in homicide rates in the 1965-1980 period.

Careful analysis, however, does not support this theory. The age

effect of the baby-boom birth cohort accounted for only about 10

percent of the increase in homicide deaths in the 1965-1980


Although media images portray vulnerable young children and the

elderly at special risk for homicide, homicide rates are

relatively low for both groups. There were 1.4 victims per 100,000

population for children between the ages of 5 and 14 in 1991, a

fraction of the rates for teenagers and young adults. 

Nonetheless, child homicides are now at or near record highs.

Homicide rates for 5- to 14-year-olds jumped 52 percent between

1985 and 1991 for blacks and 11 percent for whites. In 1991, 23.5

of every  100,000 black infants under 1 year old lost their lives

through homicide, a 72 percent increase since 1985. 

The homicide rate for elderly people (ages 75 and older) is

generally less than one-fifth the rate for 15- to 24-year-olds. In

1991, elderly blacks died from homicide at the rate of about 18.7

per 100,000 people; the comparable rate for whites is 3.1. 

Murder rates have been steadily declining for middle-aged

Americans (ages 40 to 64) since 1980. For middle-aged whites,

rates in 1990 were about the same as those observed in 1970. Rates

for middle-aged African Americans, on the other hand, are lower

than 1950 levels.  

Victims and offenders

Homicide is far from a random occurrence in our society.

Demographic characteristics of homicide victims are often similar

to those of people arrested for homicide in terms of gender, age,

and race (see figure). Among homicides for which we have gender

data, the majority of victims (77 percent) and offenders (91

percent) are men. African Americans are disproportionately likely

to be victims of homicide. While they represent only 12 percent of

the U.S. population, one-half of homicide victims and more than

half (56 percent) of offenders are African Americans. Today, the

homicide death rate for African Americans is six to seven times

that for whites. Homicide rates for whites, however, are rising

faster than those for African Americans--doubling from less than 3

to 6 per 100,000 in the past 30 years.  The racial gap has

narrowed slightly since the 1960s.

People may fear assault at the hands of a stranger or becoming a

victim of a random act of violence. In fact, victims are quite

likely to know their attackers. More than two-thirds of female

victims and about half of male victims knew their assailants. 

Most commonly, the assailant was a family member (30 percent for

female victims and 10 percent for male victims) or a personal

acquaintance (35 percent for female victims and 40 percent for

male victims). However, a recent study of arrest data, by

criminologist Alfred Blumstein of Carnegie Mellon University,

shows that murders by young people are increasingly likely to be

targeted against strangers. 

Machiko Yanagishita is a research demographer at PRB and F.

Landis MacKellar is a research scholar at the International

Institute for Applied Systems Analysis and a former Mellon

Visiting Scholar at PRB.

Homicide in the United States: Who's at Risk? by F. Landis

MacKellar and Machiko Yanagishita is available from PRB for $5,

plus $1 postage and handling, with bulk rates available. To order,

call 1-800-877-9881.


Population Doubling Time: Looking Backward

By Jessics Teisch and Alex De Sherbinin

Doubling time is a measure that dramatically illustrates the

current growth rate of a country. Defined as the number of years

it would take for a population to double, assuming a constant

growth rate, it enables one to quickly grasp the power of

compounded rates of growth. For example, at its current annual

growth rate of 3.3 percent, Liberia would double its population in

just 21 years. Norway, by contrast, with a growth rate of 0.4

percent, would take 137 years to double its population. (See

Speaking Graphically, page 6.)

But what happens if we stand this familiar measure on its head?

Suppose we look backward in time to examine when today's

population totals were half their current size. What emerges is a

striking divergence in patterns of change among the three major

developing regions--Africa, Latin American, and Asia.

What is half of 1994?

Africa. According to the United Nations' 1992 World Population

Prospects, Africa's population was half of its 1994 total in 1970,

only 24 years earlier.

At today's growth rates, with almost all African countries

growing rapidly, the region's population would double again in the

next 24 years. Ethiopia's population has doubled to 56.3 million

people since 1967 and would double again in 23 years. 

Egypt, with a 1994 population of 57.3 million, has doubled its

population since 1964 and would double again in 31 years at its

current growth rate of 2.3 percent per year. In Egypt, this growth

would occur despite strong family planning programs, primarily

because of Egypt's young population, which is a legacy of past

rapid growth. Early marriage and short intervals between births

also contribute to Egypt's high rate of growth.

Latin America. Once the world's fastest growing region, Latin

America doubled its population from 237 million to 474 million

people between 1964 and 1994--just three decades. At its current

annual growth rate of 2.0 percent, it would take somewhat

longer--38 years--to double again. 

Mexico, for instance, had half its current population size of

91.8 million people 26 years ago (in 1968) and will double again

in 33 years if the current growth rate of 2.2 percent per year

persists. Brazil--Latin America's most populous country, with

159.0 million people--had half as many people in 1963. However,

Brazil would need 43 years to double again at current rates.    

Asia. Asia is a region of contrasts. In 1961, 33 years ago,

Asia's population was 1.7 billion people, half of what it is

today. At today's rate, it would not double for another 39 years.

For some Asian countries, the slowdown in growth rates has been

sudden and dramatic. Japan's population was half its current size

of 125 million 66 years ago in 1928. At current growth rates,

however, Japan will not double again for 183 years. Some of

Japan's Asian neighbors--such as Hong Kong, South Korea, Taiwan,

and Thailand-- also have experienced dramatic drops in growth


Other Asian countries, such as Bangladesh, retain a rapid growth

rate.  In 1994, Japan and Bangladesh had the same size population:

125 million. But it took Bangladesh 26 years, or less than half as

long as Japan, to reach this size. With only 31 percent of married

women using contraception and an average of almost five children

per woman, Bangladesh has a growth rate of 2.4 percent, and a

current doubling time of 29 years.

Population doubling times are based solely on today's growth

rates, building in no assumptions about mortality or fertility

change. For a country whose fertility is coming down, the doubling

time calculation will exaggerate the actual speed of future

population growth. But any country's fertility may change in

surprising ways, so it is worth glancing back to 1957. In that

year, the world's population was half its current size--2.8

billion people. If the 1957 world population growth rate of 1.85

percent had remained constant over the years, the world today

would actually have 49 million fewer people. This is because world

population growth rates temporarily rose to a high of 2.1 percent

in the late 1960s before declining to today's level of 1.6


Although rates of growth are not expected to increase in less

developed regions over the next few decades, population momentum

will contribute to continued high growth rates--and consequently

short doubling times--in developing countries at least until the

early part of the 21st century.

Note: PRB calculated past population doubling times in 1994

based on year-by-year population estimates from the UN's 1992

World Population Prospects on diskette. Numbers from the 1994

Prospects were released just prior to publication. 


How Many People Have Ever Lived on Earth?

By Carl Haub

How many people have ever lived on earth?" This question is a

perennial one among information calls to PRB.

One reason the question keeps coming up is that somewhere, at

some time back in the 1970s, some now-forgotten writer made the

statement that 75 percent of the people who had ever been born

were alive at that moment. 

This little factoid has had a long shelf life, even though a bit

of reflection would show how unlikely it is. For this "estimate"

to be true would mean either that births in the 20th century far,

far outnumbered those in the past or that there were an

extraordinary number of extremely old people living in the 1970s.

If this estimate were true, it would indeed make an impressive

case for the rapid pace of population growth in this century. But

if we judge the idea that three-fourths of people who ever lived

are alive today to be a ridiculous statement, have demographers

come up with a better estimate? What might be a reasonable

estimate of the actual percentage?

Any such exercise can be only a highly speculative enterprise,

to be undertaken with far less seriousness than most demographic

inquiries. Nonetheless, it is a somewhat intriguing idea that can

be approached on at least a semi-scientific basis.

And semi-scientific it must be, because there are, of course,

absolutely no demographic data available for 99 percent of the

span of the human stay on earth. Still, with some speculation

concerning prehistoric populations, we can at least approach a

guesstimate of this elusive number.

Prehistory and history

Any estimate of the total number of people who have ever been

born will depend basically on two factors: (1) the length of time

humans are thought to have been on earth and (2) the average size

of the human population at different periods. 

Fixing a time when the human race actually came into existence

is not a straightforward matter. Various ancestors of Homo sapiens

seem to have appeared at least as early as 700,000 B.C. Hominids

walked the earth as early as several million years ago. According

to the United Nations' Determinants and Consequences of Population

Trends, modern Homo sapiens may have appeared about 50,000 B.C.

This long period of 50,000 years holds the key to the question of

how many people have ever been born.

At the dawn of agriculture, about 8000 B.C., the population of

the world was somewhere on the order of 5 million. (Very rough

figures are given in the table on page 5; these are averages of an

estimate of ranges given by the United Nations and other sources.)

The slow growth of population over the 8,000-year period, from an

estimated 5 million to 300 million in 1 A.D., results in a  very

low growth rate--only 0.0512 percent per year. It is difficult to

come up with an average world population size over this period. In

all likelihood, human populations in different regions grew or

declined in response to famines, the vagaries of animal herds,

hostilities, and changing weather and climatic conditions.

In any case, life was short. Life expectancy at birth probably

averaged only about 10 years for most of human history.  Estimates

of average life expectancy in Iron Age France have been put at

only 10 or 12 years. Under these conditions, the birth rate would

have to be about 80 per 1,000 people just for the species to

survive. Today, a high birth rate would be about 45-50 per 1,000

population, observed in only a few countries of Africa and in

several Middle Eastern states that have young populations.

Our birth rate assumption will greatly affect the estimate of

the number of persons ever born. Infant mortality in the human

race's earliest days is thought to have been very high--perhaps

500 infant deaths per 1,000 births, or even higher. Children were

probably an economic liability among hunter-gatherer societies, a

fact that is likely to have led to the practice of infanticide.

Under these circumstances, a disproportionately large number of

births would be required to maintain population growth, and that

would raise our estimated number of the "ever born."

By 1 A.D., the world may have held about 300 million people. One

estimate of the population of the Roman Empire, from Spain to Asia

Minor, in 14 A.D. is 45 million. However, other historians set the

figure twice as high, suggesting how imprecise population

estimates of early historical periods can be.

By 1650, world population rose to about 500 million, not a large

increase over the 1 A.D. estimate. The average annual rate of

growth was actually lower from 1 A.D. to 1650 than the rate

suggested above for the 8000 B.C. to 1 A.D. period. One reason for

this abnormally slow growth was the Black Plague. This dreaded

scourge was not limited to 14th century Europe. The epidemic may

have begun about 542 A.D. in Western Asia, spreading from there.

It is believed that half the Byzantine Empire was destroyed in the

6th century, a total of 100 million deaths. Such large

fluctuations in population size over long periods greatly compound

the difficulty of estimating the number of people who have ever


By 1800, however, world population had passed the 1 billion

mark, and it has continued to grow since then to the current 5.7



Guesstimating the number of people ever born, then, requires

selecting population sizes for different points from antiquity to

the present and applying assumed birth rates to each period (see

table). We start at the very, very beginning--with just two people

(a minimalist approach!).

One complicating factor is the pattern of population growth. Did

it rise to some level and then fluctuate wildly in response to

famines and changes in climate? Or did it grow at a constant rate

from one point to another? We cannot know the answers to these

questions, although paleontologists have produced a variety of

theories. For the purposes of this exercise, it was assumed that a

constant growth rate applied to each period up to modern times.

Birth rates were set at 80 per 1,000 per year through 1 A.D. and

at 60 per 1,000 from 2 A.D. to 1750. Rates then declined to the

low 30s by the modern period.  (For a brief bibliography of

sources consulted in the course of this alchemy, see References).

This semi-scientific approach yields an estimate of about 105

billion births since the dawn of the human race. Clearly, the

period 8000 B.C. to 1 A.D. is key to the magnitude of our number,

but, unfortunately, little is known about that era. Some readers

may disagree with some aspects--or perhaps nearly all aspects--of

the table, but at least it offers one approach to this elusive

issue. If we were to make any guess at all, it might be that our

method underestimates the number of births to some degree. The

assumption of constant population growth in the earlier period may

underestimate the average population size at the time. And, of

course, pushing the date of humanity's arrival on the planet

before 50,000 B.C. would also raise the number, although perhaps

not by terribly much.

So, our estimate here is that about 5.5 percent of all people

ever born are alive today. That's actually a fairly large

percentage when you think about it.


Nathan Keyfitz. Applied Mathematical Demography. New York: John

Wiley and Sons, 1976.

Judah Matras. Population and Societies. Englewood Cliffs, NJ:

Prentice-Hall, 1973.

Colin McEvedy and Richard Jones. Atlas of World Population

History. New York: Facts on File, 1978.

United Nations. Determinants and Consequences of Population

Trends. New York: United Nations, 1973.

------. World Population Prospects As Assessed in 1963. New

York: United Nations, 1966.

------. World Population Prospects As Assessed in 1992. New

York: United Nations, 1993.



Population: 8.4 million

Land area: 42,680 square miles

Births: 11 per 1,000

Deaths: 13 per 1,000

Infant deaths: 15.9 per 1,000 live births

Natural increase: -0.2 percent

Total fertility: 1.5 births per woman

Life expectancy: 68(male)/75(female)

Capital city: Sofia

By Rafael Obregon

The Republic of Bulgaria lies in the eastern Balkans, in

southeastern Europe. Almost the size of the state of Virginia,

with a population about equal to that of New Jersey, it shares

borders with Romania to the north, Turkey and Greece to the south,

and Serbia and Macedonia to the west. The climate is mostly

Mediterranean. Most Bulgarians are of Slavic origin. Although no

ethnic minorities are officially identified, about 10 percent of

the population is of Turkish origin, and a small percentage are


Under the rule of the Ottoman Empire for five centuries,

Bulgaria received full independence in 1908. Bulgaria allied

itself with Germany in World War I and World War II. In 1944 the

Fatherland Front, a left-wing alliance supported by the Soviet

Union, seized power. The monarchy was abolished in 1946, leading

to a Soviet-style constitution in 1947. Bulgaria remained under

Bulgarian Communist Party rule until the waning of the Soviet

influence over Eastern Europe in the late 1980s. Free elections

were held in 1988. In 1992, Zhelyu Zhelev, from the Union of

Democratic Forces, was elected president for a four-year term.

Like other former Soviet-bloc states, Bulgaria is going through

an economic transition, with private ownership and investment

increasing. Although Bulgaria has a relatively low debt to the

West among Eastern European countries, the debt rose from US $4.1

billion in 1986 to $6.0 billion in 1988, and anti-inflationary

measures were introduced in 1991.

Over the past few years Bulgaria's economy has shifted from

primarily agriculture to manufacturing. The labor force in

agriculture and forestry declined from 44 percent of the total

working population to 24 percent between 1965 and 1975. By

contrast, engineering and electronics have developed rapidly.  

Bulgaria is now experiencing  natural decrease (more deaths than

births): an estimated -0.2 percent in 1994.  In 1992, the total

population decreased by 19,000 people. Men made up nearly 70

percent of this decline, probably reflecting economic emigration

of young men to Western Europe and gender differences in mortality

at older ages.  

At an average 1.5 births per woman, fertility levels are well

below replacement levels, although Bulgarian women report an ideal

family size of two children. The United Nations Population Fund

(UNFPA) estimates the contraceptive prevalence rate at less than

20 percent of married women, which suggests that withdrawal and

abortion are the chief methods of limiting births. Modern

contraceptives such as IUDs and condoms are not widely used, and

birth control pills are too expensive for many Bulgarians. Turkish

minority women have higher fertility, according to UNFPA, and this

differential fertility has become a political issue in Bulgaria. 

Migration has contributed to population decline. An estimated

300,000 Bulgarians of Turkish ancestry fled to Turkey in 1985,

following pressures from the Bulgarian government for them to

adopt Slavic names. Nearly 200,000 Bulgarians have left the

country as economic migrants to Western Europe between 1989 and


Another factor, although less significant, is the steady

increase in mortality rates (from 8.1 to 12.6 per 1,000 population

between 1960 and 1992), due to the aging of the population. The

average age is 38.7 years. Life expectancy has fallen in the last

few years, from 71.2 years in 1989 to 70.9 years in 1992.

The profound changes taking place in Bulgaria also affect

population policies. Future population policies will focus on

issues such as fertility replacement levels, dependence on

abortion as a means of fertility control, mortality reduction, and

improvement of socioeconomic conditions for different sectors of

society, particularly women and younger people.


Census and the Post Office: Together at last?

Legislation signed by President Clinton in November promises to

improve accuracy and reduce costs in the 2000 Census. 

The Census Address List Improvement Act of 1994 will allow the

Census Bureau to check its address list with that of the Post

Office. Under the act, local governments will designate census

liaisons, authorized to check Census Bureau addresses against the

Post Office list. State and local governments may provide other

address information. 

Built-in measures protect privacy and prevent misuse of the

information. It is hoped that the new procedure will help the

bureau get 2000 Census forms out accurately by mail to the highest

possible percentage of households, thus improving mail-back

returns. [See: Congressional Record, October 3, 1994, page


New sex survey data on CD-ROM

The 1992 National Health and Social Life Survey (NHSLS) will be

available this April from Sociometrics, on mainframe tape or CD-

ROM. Based on interviews with a representative sample of 3,432 men

and women, the NHSLS is the most comprehensive data ever gathered

on U.S. sexual behavior, covering early sexual experiences,

contraception and fertility, sexual abuse, satisfaction,

homosexuality, and other topics.

Contact: Sociometrics, 170 State Street, Suite 260, Los Altos,

CA 94022, 415-949-3282. Archived as AIDS/STD Data Set Nos. 12-13.

World Social Summit in March

The first-ever World Summit for Social Development, to be held

March 6-12 in Copenhagen, will bring heads of state together to

find ways to work on social development and human security issues. 

The conference will focus on poverty alleviation, generation of

employment, and what is being referred to as "social integration"

(alleviation of social inequities and increasing social cohesion). 

For information, contact Ritu Sharma, Academy for Educational

Development, 202-884-8145, or  Patty Petesch, Overseas Development

Council (ODC), 202-234-8701. ODC has a readable short report from

its June conference: A New Agenda for Social Development: Social

Summit. E-mail the United Nations at ngls@igc.apc.org or download

draft conference documents from igc.apc.un.socdev.docsconference. 

Greenhouse gases per capita

The United Arab Emirates (UAE) and the United States lead the

world in per capita emissions of carbon dioxide, says a new

wallchart from Population Action International. In 1990, UAE

emissions reached 33.1 metric tons per capita; U.S. emissions,

almost 20 tons. Canada, Australia, Saudi Arabia, Singapore,

Czechoslovakia, the countries of the former USSR (taken as a

group), Trinidad and Tobago, Kuwait, Norway, Germany, North Korea,

and Finland all rank between 10 and 16 metric tons per capita. 

Given the 1990 world population of 5.3 billion people, the

emissions level needed to stabilize CO2 levels would have averaged

1.69 tons of CO2 per person. Currently about half the world's

countries--all of them less developed countries--fall beneath that

threshold. As world population grows, the threshold falls, notes

the report, making a sustainable climate more difficult to


Sources: "People, Carbon Dioxide and a Stable Atmosphere: A

Ranking of 126 Countries by 1990 Per Capita Emissions of CO2" ($5)

and Stabilizing the Atmosphere: Population, Consumption and

Greenhouse Gases, Population Action International ($8), 202-659-


New books

Population, Law, and the Environment, by Robert M. Hardaway.

Westport, CT: Praeger Publishers, 1994. 177 pages. $55.00. ISBN 0-


Western Hemisphere Immigration and U.S. Foreign Policy,

Christopher Mitchell, ed. University Park, PA: Penn State

University Press, 1992. 314 pages. $14.95. ISBN 0-271-00791-5.

Population and Reproductive Rights: Feminist Perspective from

the South, by Sonia Correa and Rebecca Reichmann. London: Zed

Books Ltd., 1994. 136 pages. $17.50. ISBN 1-85649-284-2. 

Modern Barrier Methods: Effective Contraception and Disease

Prevention, by Paul Feldblum and Carol Joanis. Research Triangle

Park, NC: Family Health International, 1994. 64 pages. $13.95.

ISBN 0-939704-19-6. 

For further information, please contact: popin@undp.org
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