As far as we know, there is no comparable data for any other country up until the mid-eighteenth century see the following section for Sweden , where recordkeeping began in The chart shows the birth and death rates in England and Wales over the span of nearly years. As we can see, a growing gap opens up between the birth and death rate after , creating a population explosion.
Statistics Sweden, the successor of the Tabellverket, publishes data on both deaths and births since recordkeeping began more than years ago. These records suggest that around the year , the Swedish death rate started falling, mainly due to improvements in health and living standards, especially for children.
Yet while death rates were falling, birth rates remained at a constant pre-modern level until the s. During this period and up until the first half of the 20th century, there was a sustained gap between the frequency of deaths and the frequency of births. It was because of this gap that the Swedish population increased. The following visualization supports these observations. The visualization presents the birth and death rate for all countries of the world over the last 5 decades.
Countries per continent can also be highlighted by hovering and clicking on them in the legend on the right side of the chart. By visualising this change we see how in country after country the death rate fell and the birth rate followed — countries moved to left-hand-side first and then fell to the bottom left corner. Today, different countries straddle different stages of the model. Most developed countries have reached stage four and have low birth and death rates, while developing countries continue to make their way through the stages.
There are two important relationships that help explain how the level of development of a country affects its population growth rates:. Combining these two relationships, we would expect that as a country develops, population growth rates decline. Generally, this is true. Over the last two decades we have seen declining population growth rates in countries at all stages of development.
In the average woman on the planet had 5 children. The first panel in this chart shows this fundamental change. The total fertility rate at which a population replaces itself from one generation to the next is called the replacement fertility rate. If no children died before they grew up to have children themselves the replacement fertility rate would be 2. Because some children die , the global replacement fertility rate is currently 2.
Why then is global population growth not coming to an end yet? The number of births per woman in the reproductive age bracket is only one of two drivers that matter here. The second one is the number of women in the reproductive age bracket. If there were few women in the reproductive age bracket the number of births will be low even when the fertility rate is high.
At times when an increasing share of women enter the reproductive age bracket the population can keep growing even if the fertility rate is falling. The second chart in this panel shows that the population growth over the last decades resulted in increasingly larger cohorts of women in the reproductive age bracket.
As a result, the number of births will stay high even as the number of births per woman is falling. This is what the bottom panel in the chart shows.
According to the UN projections, the two drivers will cancel each other out so that the number of births will stay close to the current level for many decades. The number of births is projected to change little over the course of this century. In the middle of the 21st century the number of births is projected to reach a peak at million and then to decline slowly to million births by The coming decades will be very different from the last.
How close we are to peak child we looked at in a more detailed post. Population momentum is one important driver for high population growth. But it of course also matters that all of us today live much longer than our ancestors just a few generations ago.
Life expectancy is now twice as long in all world regions. In all of this it is important to keep in mind that these are projections and how the future will actually play out will depend on what we are doing today.
Population momentum is driven by the increasingly large cohorts of women in the reproductive age bracket. And this is when global population growth will come to an end. Hans Rosling explained it better than anyone , with the help of toilet rolls. At the global level, population changes are determined by the balance of only two variables: the number of people born each year, and the number who die. How large of an impact does migration have on population changes across the world? In the United States we see that since the early s, migration into the USA has exceeded emigration out of the country.
This means net migration has been positive, and resulted in a higher population growth rate than would have occurred in the scenario with zero migration. In , for example, the actual population growth rate was 0. With zero migration, this would have been 0. This is also true for most countries across Europe. In fact, population growth would have been negative i. In , the European population increased by 0. The opposite is of course true for countries where emigration out of the country is higher than immigration.
Take Nepal as an example: in the mids its actual population growth rate has been lower than it would have been in the absence of migration. In , its growth rate was 0. With zero migration it would have been 1. This article previously covered aspects of population age structure; you now find this material in our entry on Age Structure.
We evaluate the track record of the UN projections in the entry on future population growth. But historic and current population estimates between sources are also not identical. How do these sources compare? In the chart we see the comparison between the UN shown in red and US Census Bureau in blue estimates globally and by region.
Global estimates have varied by around 0. The largest variation comes from estimates of Asia, Africa and Latin America — where census data and underlying data sources will be less complete and lower quality.
This means some interpretation and judgement is necessary from expert demographers within each organization. Quoting them to more gives a false sense of precision. Across the sources, we can say that there were 7. The most discussed estimates of world population from the last century are those from the UN Population Division.
These estimates are revised periodically and aim to be consistent and comparable within and across countries and time. In short, estimates of the population in the past i.
The estimates of these components are taken directly from national statistical sources or—where only partial or poor-quality data exists—are estimated by the Population Division staff. Population counts from periodic censuses are used as benchmarks. One of the main implications of using the cohort-component method is that it sometimes leads to marked inconsistencies with official country statistics. The standard methodology used for producing population estimates relies on the so-called cohort-model.
Providing high-quality estimates requires reliable and up-to-date census data. Crucial to population estimates are birth and mortality rates: this census data therefore relies birth registration and death reporting.
The two maps show the completeness of birth and death reporting across the world. Many countries, particularly those in the least developed regions of the world, have limited census data. For countries with no data in one or two decades before each revision, the UN relies on other methodologies. One is to derive estimates by extrapolating trends from countries in the same region with a socio-economic profile considered close to the country in question.
As discussed in the previous section, there are a number of studies providing historic population data. The most commonly cited source is McEvedy and Jones This above source is an input used in producing the HYDE project data, as well as other datasets.
Further references to this source are available in Goldewijk, K. Long-term dynamic modelling of global population and built-up area in a spatially explicit way: HYDE 3. The Holocene. Historical population data on a sub-national level — including their administrative divisions and principal towns — is collected by Jan Lahmeyer and published at his website www.
The Minnesota Population Center publishes various high-quality datasets based on census data beginning in At the time of writing this source was online at www. Ultimately the highest population growth rate is also found there, the country with the highest population growth rate is Lebanon. This could be due to a low infant mortality rate in Lebanon or the ever -expanding tourism sector.
More importantly, Lebanon is also the country with the highest net migration rate in the world. Loading statistic Show source. Download for free You need to log in to download this statistic Register for free Already a member?
Log in. Show detailed source information? Register for free Already a member? More information. Supplementary notes. Other statistics on the topic. International Countries with the largest gross domestic product GDP per capita International Countries with the largest gross domestic product GDP International The 20 countries with the lowest gross domestic product GDP per capita in Economy Leading export countries worldwide Throughout the 20th century each additional billion has been achieved in a shorter period of time.
Human population entered the 20th century with 1. The growth of the last years appears explosive on the historical timeline. The overall effects of this growth on living standards, resource use, and the environment will continue to change the world landscape long after.
As long ago as , Thomas Malthus studied the nature of population growth in Europe. He claimed that population was increasing faster than food production, and he feared eventual global starvation.
Of course he could not foresee how modern technology would expand food production, but his observations about how populations increase were important. Population grows geometrically 1, 2, 4, 8 … , rather than arithmetically 1, 2, 3, 4 … , which is why the numbers can increase so quickly.
A story said to have originated in Persia offers a classic example of exponential growth. It tells of a clever courtier who presented a beautiful chess set to his king and in return asked only that the king give him one grain of rice for the first square, two grains, or double the amount, for the second square, four grains or double again for the third, and so forth.
The king, not being mathematically inclined, agreed and ordered the rice to be brought from storage.
The eighth square required grains, the 12th took more than one pound. Long before reaching the 64th square, every grain of rice in the kingdom had been used. Even today, the total world rice production would not be enough to meet the amount required for the final square of the chessboard. The secret to understanding the arithmetic is that the rate of growth doubling for each square applies to an ever-expanding amount of rice, so the number of grains added with each doubling goes up, even though the rate of growth is constant.
At a 3 percent growth rate, its doubling time — or the number of years to double in size — is 23 years. The growth rate of 1. Because of the large and increasing population size, the number of people added to the global population will riain high for several decades, even as growth rates continue to decline. Between and , most of this annual growth will occur in the less developed countries in Africa, Asia, and Latin America whose population growth rates are much higher than those in more developed countries.
The populations in the less developed regions will most likely continue to command a larger proportion of the world total. The more developed countries in Europe and North America, as well as Japan, Australia, and New Zealand, are growing by less than 1 percent annually. Population growth rates are negative in many European countries, including Russia If the growth rates in these countries continue to fall below zero, population size would slowly decline.
The number of years required for the population of an area to double its present size, given the current rate of population growth. Population doubling time is useful to demonstrate the long-term effect of a growth rate, but should not be used to project population size.
Many more-developed countries have very low growth rates. But these countries are not expected to ever double again. Most, in fact, likely have population declines in their future. Many less-developed countries have high growth rates that are associated with short doubling times, but are expected to grow more slowly as birth rates are expected to continue to decline. This is a complex issue. Rapid population growth in less developed countries is linked to many problems—including poverty, hunger, high infant mortality, and inadequacies in social services, health services, and infrastructure transportation, communication, etc.
It would be a gross oversimplification to say that population growth causes these problems. Population growth could just as easily have been the effect of economic insecurity and poor health care. However, rapid population growth may defeat efforts to combat poverty and hunger and to improve services, as increasing numbers of people put serious pressures on the economy and society of poor nations.
Poverty, for example, existed long before the recent period of rapid population growth. An assessment of poverty must consider the amount and type of natural resources, including minerals and geographic features that a country possesses or lacks.
In areas where power and wealth are concentrated in the hands of a few, it is difficult for the poor to break out of the cycle of poverty that is often passed from generation to generation.
Rapid population growth makes this effort even more difficult. Hunger has always been a companion to poverty. However, rapid population growth may intensify the hunger problem; in the most rapidly growing countries, population growth can reduce or eliminate food production gains resulting from modernization of farming. Population pressures may also encourage practices such as overirrigation and overuse of croplands, which undermine the capacity to feed larger numbers.
In some cases, population growth is quite directly related to a social problem because it increases the absolute numbers whose needs must be met. For example, some less developed countries have made enormous progress in increasing the percentage of children enrolled in school. However, because of population growth during the same period, the number of children who are not enrolled in school also increased because there were insufficient resources to meet the growing need.
Similar observations could be made about jobs, housing, sanitation, and other human needs. These problems are compounded when large numbers migrate from rural to urban areas and increase the burden placed on already inadequate supplies and services. A listing of country definitions is published annually in the United Nations Demographic Yearbook.
Through most of history, the human population has lived a rural lifestyle, dependent on agriculture and hunting for survival.
By , almost 14 percent were urbanites, although only 12 cities had 1 million or more inhabitants. The number of cities with over 1 million people had grown to The world has experienced unprecedented urban growth in recent decades. There were more than cities over 1 million and 19 over 10 million.
More developed nations were about 74 percent urban, while 44 percent of residents of less developed countries lived in urban areas. However, urbanization is occurring rapidly in many less developed countries. It is expected that 70 percent of the world population will be urban by , and that most urban growth will occur in less developed countries. What is an urban area? An urban area may be defined by the number of residents, the population density, the percent of people not dependent upon agriculture, or the provision of such public utilities and services as electricity and education.
Some countries define any place with a population of 2, or more as urban; others set a minimum of 20, There are no universal standards, and generally each country develops its own set of criteria for distinguishing urban areas.
The United States uses a population density measure to define urban with a minimum population requirement of 2, The classification of metropolitan includes both urban areas as well as rural areas that are socially and economically integrated with a particular city. When comparing countries it is often helpful to look beyond the proportion of populations that are rural or urban and instead consider the size of cities.
Countries differ markedly in the distribution of their urban population. For example, many urban dwellers in Africa live in cities of fewer than 10, residents. In Argentina, 92 percent of the population was urban, and 32 percent of these people lived in just one city, Buenos Aires. Only 8 percent of Americans live in cities of 1 million or more. A city grows through natural increase—the excess of births over deaths—and because the in-migration of people from other cities, rural areas, or countries is greater than out-migration.
More developed and less developed countries of the world differ not only in the percent living in cities, but also in the way in which urbanization is occurring. During the 19th and early 20th centuries, urbanization resulted from and contributed to industrialization. New job opportunities in the cities spurred the mass movement of surplus population away from the countryside.
At the same time, migrants provided cheap, plentiful labor for the emerging factories. While the proportion increased through rural to urban migration, high death rates in the cities slowed urban growth. Cities were unhealthy places because of crowded living conditions, the prevalence of contagious diseases, and the lack of sanitation.
Until the mids, the number of deaths exceeded births in many large European cities. Migration accounted for as much as 90 percent of city growth during this period. Urbanization in most less developed countries in the past 50 years contrasts sharply with the experience of the more developed countries.
Death rates have fallen faster in urban areas because of greater access to health services. Because birth rates are relatively high in most less developed countries, the rates of natural increase are also quite high in cities. Migration also fuels urban growth in less developed countries as people leave the countryside in search of better jobs. New York and London are typical of large cities in more developed countries that arose in the s and early s, reached their current size mid-century, and have since experienced slow growth or decline.
Cities in some less developed countries, such as Mexico City, grew very rapidly between and , and are growing more slowly now. Many Asian and African cities, such as Lagos and Bombay, are experiencing very rapid growth now and are projected to continue at this pace. As the population increases, more people will live in large cities. Many people will live in the growing number of cities with over 10 million inhabitants, known as megacities.
Megacities numbered 16 in By , 27 megacities will exist, 21 in less developed countries. A large concentration of population, usually an area with , or more people. The area typically includes an important city with 50, or more inhabitants and the administrative areas bordering the city that are socially and economically integrated with it.
Refers to the population contained within the contours of a contiguous territory inhabited at urban density levels without regard to administrative boundaries. It usually incorporates the population in a city or town plus that in the sub-urban areas lying outside of but being adjacent to the city boundaries. Since , birth rates have dropped, sometimes quite rapidly, in many less developed countries.
This is an encouraging sign to those governments that have identified rapid population growth as an obstacle to their development goals.
Declines have occurred in settings that vary widely. In an attempt to influence the population size and composition of their country, governments have established population policies. Research studies have found that organized programs to make family planning information and services widely available have the most immediate results and cost less than other programs.
Less developed countries that have implemented successful programs have made a strong political commitment to culturally sensitive, conveniently located outreach programs that offer users a wide variety of family planning methods. In particular, programs in which female family planning workers visit women in their homes bring about a tremendous increase in the use of contraception.
The importance of this factor is reinforced by a reanalysis of the fertility decline in 19th century Europe. The study found that a change in cultural attitudes toward the acceptability of limiting family size was as essential as the social and economic improvements that were occurring. However, to reduce fertility to the level required to bring about slow population growth, social and economic improvement is necessary as well.
Couples living in extreme poverty have little reason to think that having fewer children would improve their lives. Children may indeed represent their future security since many people depend on their children for household and agricultural work and for support in old age. Studies have found that when poor families achieve a certain level of income there is a drop in fertility.
The availability of family planning services can help translate ideas about smaller family size into reality. The status of women also affects fertility levels.
Many women, especially in less developed countries, have few choices in life outside of marriage and children and tend to have large families.
Investing in women, by providing education, health, and other services, helps to expand their opportunities and reduce their dependence on children for status and support. Immigration policies are also used to regulate population growth. Some countries openly encourage emigration to relieve crowding and unemployment. Other countries restrict the number of people who may enter and become citizens. Some countries absorb many illegal immigrants despite specific policy choices, and others may choose to accept a large number of refugees.
The conscious effort of couples to regulate the number and spacing of births through artificial and natural methods of contraception. Explicit or implicit measures instituted by a government to influence population size, growth, distribution, or composition. The population of the world surged from 2.
The number of children that a couple will have is determined by many factors, including health, religion, culture, economic status, and the ability to have the number they wish to have. Many of these factors relate to the status of women—the social, economic, and cultural circumstances of women in society and of individual women in different societies.
Biological, cultural, and socioeconomic conditions together determine the number of children that a woman will have. These conditions influence her exposure to intercourse and her ability to conceive a child, as well as the number of children she may wish to have.
Some factors include age at marriage, use of family planning methods, and breastfeeding. Many socioeconomic factors are also important influences on fertility.
These factors are sometimes indirectly related. Education, urbanization, labor force participation, and infant mortality have a strong correlation with levels of fertility. But it is difficult to determine direct causation and one must be careful not to confuse causation with correlation. Some factors may be merely related to fertility rates, and other unknown factors may be the real cause of different levels of fertility among different women and different societies.
Generally, the age at which a woman first marries is directly related to the number of children she will bear because it affects the length of time she will be at risk of becoming pregnant.
The total fertility rate—or average births per woman—for women in the United States, who marry around age 25, is 2. Conversely, women in Niger, who marry earlier, average 7. Within countries, rural women tend to marry earlier than urban women and tend to have larger families. Access to contraception is an important contributor to the differences in the fertility rates among countries, but culture and socioeconomics weigh heavily as well.
Studies show that women who have completed primary school have fewer children than those with no education. Education is key because educated women are more likely to know what social, community, and health services, including family planning, are available and to have the confidence to use them. In addition, women with more education have more opportunities outside the home and can see the benefits of education for their children.
Women who achieve a relatively high level of education are also more likely to enter the labor force before they marry or begin childbearing, and ultimately to have smaller families than women who marry in their teens.
This trend is evident in almost every country where data are available. Evidence shows that efforts to lower birth rates may depend on improving the status of women.
Part of the Cairo Programme of Action, developed at the International Conference on Population and Development, calls for universal access to education, employment opportunities for women, and an end to discrimination against women.
Experiences in some countries have shown that fertility patterns can change in as little as a decade, and that voluntary policies and programs can be highly effective in encouraging the change. Resource Library. When could world population stop growing? Find out the answers to these questions and more. Change Three Patterns of Population Change.
Which of the three countries has the greatest proportion of people ages 65 and older? Reading How can the age-sex structure of a population help determine the needs of that population? How can migration affect the shape of a pyramid?
Which pyramid represents this concept? The age dependency ratio for the United States is shown below at Calculate the dependency ratios for Kenya, Germany, Brazil, and Japan. Compare the components of each of them. Terms Age-Sex Structure The composition of a population as determined by the number or proportion of males and females in each age category. Baby Boom A dramatic increase in fertility rates and in the absolute number of births. As population growth continues to decline, the curve representing the world population is getting less and less steep.
By the end of the century — when global population growth will have fallen to 0. It is hard to know the population dynamics beyond ; it will depend upon the fertility rate and as we discuss in our entry on fertility rates here fertility is first falling with development — and then rising with development.
The question will be whether it will rise above an average 2 children per woman. The world enters the last phase of the demographic transition and this means we will not repeat the past. The global population has quadrupled over the course of the 20th century, but it will not double anymore over the course of this century. We are on the way to a new balance. The big global demographic transition that the world entered more than two centuries ago is then coming to an end: This new equilibrium is different from the one in the past when it was the very high mortality that kept population growth in check.
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