Where in the World Do Most Teen Have Babies
When and why did the world population grow? And how does rapid population growth come to an stop? These are the big questions that are fundamental to this inquiry article.
The world population increased from ane billion in 1800 to 7.ix billion today.
The world population growth rate declined from ii.2% per yr l years ago to 1.0% per yr.
Other relevant research:
Future population growth – This article focuses on the future of population growth. We explain how nosotros know that population growth is coming to an end, and present projections of the drivers of population growth.
Life expectancy – Improving health leads to falling mortality and is therefore the cistron that increases the size of the population. Life expectancy, which measures the age of death, has doubled in every region in the earth as we show here.
Kid & infant mortality – Mortality at a young age has a specially big impact on demographic change.
Fertility rates – Rapid population growth has been a temporary phenomenon in many countries. It comes to an finish when the average number of births per woman – the fertility rate – declines. In the commodity we show the data and explain why fertility rates declined.
Age Structure – What is the historic period contour of populations around the earth? How did it change and what will the age structure of populations look similar in the future?
All our charts on Earth Population Growth
How is the global population distributed across the world?
Ane way to sympathise the distribution of people across the earth is to reform the earth map, not based on surface area but according to population.
This is shown here in a population cartogram: a geographical presentation of the world where the size of the countries are non drawn co-ordinate to the distribution of state, just according to the distribution of people. The cartogram shows where in the world the global population was at abode in 2018.
The cartogram is made upward of squares, each of which represents one-half a million people of a land's population. The 11.5 one thousand thousand Belgians are represented by 23 squares; the 49.five 1000000 Colombians are represented past 99 squares; the 1.415 billion people in Communist china are represented by 2830 squares; and the entire earth population of seven.633 billion people in 2018 is represented by the total sum of xv,266 squares.
Every bit the size of the population rather than the size of the territory is shown in this map y'all can see some big differences when you compare information technology to the standard geographical map we're near familiar with. Pocket-sized countries with a high population density increment in size in this cartogram relative to the world maps we are used to – look at Bangladesh, Taiwan, or the Netherlands. Large countries with a small population shrink in size (wait for Canada, Mongolia, Australia, or Russia).
Yous can find more than details on this cartogram in our explainer: 'The map nosotros need if we want to think well-nigh how global living atmospheric condition are changing'.
[click on the cartogram to enlarge it. And here y'all can download the population cartogram in high resolution (6985×2650).]
Which countries are most densely populated?
Our understanding of the world is often shaped by geographical maps. Merely this tells us aught about where in the world people live. To sympathise this, nosotros need to look at population density.
In the map we see the number of people per square kilometer (km2) across the world.
Globally the average population density is 61 people per km2, just at that place are very large differences across countries.
- Many of the world's pocket-size island or isolated states have large populations for their size. Macao, Monaco, Singapore, Hong Kong and Gibraltar are the 5 near densely populated. Singapore has well-nigh 8,000 people per kmii – more than than 200 times as dense equally the United states of america, and 2000 times that of Commonwealth of australia.
- Of the larger countries1, Bangladesh is the almost densely-populated with 1,252 people per foursquare kilometer; this is almost three times as dense equally its neighbor, India. It's followed by Lebanese republic (595), South Korea (528), holland (508) and Rwanda (495 per kmii) completing the pinnacle five.
- If you hover the mouse on the subclass from 0 to 10 on the legend then you see the earth'south to the lowest degree densely populated countries. Greenland is the to the lowest degree dense, with less than 0.2 people per foursquare km2, followed by Mongolia, Namibia, Australia and Republic of iceland. In our population cartogram these are the countries that take up much less space than on a standard geographical map.
If we want to understand how people are distributed beyond the globe, another useful tool is the population cartogram: a geographical presentation of the world where the size of the countries are not fatigued according to the distribution of country, but co-ordinate to the distribution of people.
Here we show how the globe looks in this way. When we see a standard map we tend to focus on the largest countries by area. Simply these are non e'er where the greatest number of people alive. It'due south this context we demand if nosotros want to empathize how the lives of people around the world are irresolute.
How has globe population growth changed over time?
Earth population from 10,000 BC to today
The nautical chart shows the increasing number of people living on our planet over the last 12,000 years. A mind-boggling alter: The earth population today that is ane,860-times the size of what information technology was 12 millennia ago when the world population was around iv million – half of the current population of London.
What is striking well-nigh this chart is of form that near all of this growth happened only very recently. Historical demographers estimate that around the year 1800 the world population was only around 1 billion people. This implies that on average the population grew very slowly over this long time from 10,000 BCE to 1700 (by 0.04% annually). After 1800 this inverse fundamentally: The globe population was around 1 billion in the year 1800 and increased 7-fold since then.
Around 108 billion people have ever lived on our planet. This means that today'southward population size makes up half dozen.v% of the full number of people e'er born.ii
For the long period from the appearance of mod Homo sapiens up to the starting point of this chart in 10,000 BCE it is estimated that the total world population was oftentimes well under one million.three
In this period our species was oftentimes seriously threatened by extinction.4
The interactive visualization is hither. And you tin can also download the annual world population data produced by Our World in Data.
A number of researchers have published estimates for the total world population over the long run, we have brought these estimates together and you can explore these various sources here.
Explore the interactive version of this chart
How has the earth population growth rate inverse?
In terms of recent developments, the data from the United nations Population Division provides consistent and comparable estimates (and projections) within and beyond countries and time, over the last century. This information starts from estimates for 1950, and is updated periodically to reflect changes in fertility, mortality and international migration.
In the section above we looked at the absolute change in the global population over time. But what about the charge per unit of population growth?
The global population growth rate peaked long ago. The chart shows that global population growth reached a peak in 1962 and 1963 with an annual growth rate of ii.2%; but since then, world population growth has halved.
For the terminal half-century we take lived in a world in which the population growth rate has been declining. The Un projects that this turn down will keep in the coming decades.
A mutual question we're asked is: idue south the global population growing exponentially? The answer is no. For population growth to be exponential, the growth rate would have exist the same over time (east.g. ii% growth every year). In accented terms, this would result in an exponential increase in the number of people. That'due south considering nosotros'd exist multiplying an ever-larger number of people by the same two%. 2% of the population this yr would be larger than ii% last twelvemonth, and so on; this ways the population would abound exponentially.
But, as we meet in this nautical chart, since the 1960s the growth charge per unit has been falling. This means the globe population is not growing exponentially – for decades now, growth has been more similar to a linear trend.
The accented annual change of the population
The previous department looked at the growth rate. This visualization here shows the annual global population increase from 1950 to today and the project until the end of this century.
The accented increase of the population per year has peaked in the late 1980s at over 90 meg additional people each twelvemonth. But it stayed high until recently. From now on the United nations expects the annual increase to decline by effectually 1 million every year.
Population growth over the long run
At that place are other means of visually representing the change in charge per unit of world population growth. 2 examples of this are shown in the charts below.
How long did it take for the world population to double?
The visualization shows how strongly the growth rate of the world population changed over time. In the by the population grew slowly: information technology took nearly seven centuries for the population to double from 0.25 billion (in the early on 9th century) to 0.five billion in the middle of the 16th century. As the growth rate slowly climbed, the population doubling time fell merely remained in the lodge of centuries into the first half of the 20th century. Things sped upwards considerably in the eye of the 20th century.
The fastest doubling of the world population happened betwixt 1950 and 1987: a doubling from 2.5 to 5 billion people in just 37 years — the population doubled within a little more than one generation. This flow was marked by a summit population growth of 2.1% in 1962.
Since so, population growth has been slowing, and along with it the doubling time. In this visualisation we accept used the United nations projections to show how the doubling time is projected to change until the end of this century. By 2100, it volition once once again take taken approximately 100 years for the population to double to a predicted x.eight billion.
How long did it take for the world population to increment by ane billion?
This visualization provides an boosted perspective on population growth: the number of years it took to add 1 billion to the global population. Likewise shown in this figure is the number of years projected up to 11 billion based on the UN's 'medium variant' project.
This visualisation shows again how the population growth rate has inverse dramatically through time. It wasn't until 1803 that the world reached its first billion; it then took another 124 years to attain 2 billion. By the third billion, this menstruation had reduced to 33 years, reduced farther to xv years to reach iv. The period of fastest growth occurred through 1975 to 2011, taking only 12 years to increase by i billion for the 5th, 6th and 7th.
The world has at present surpassed this peak rate of growth, and the flow between each billion is expected to continue to rising. Information technology's estimated to take approximately xiii years to accomplish eight billion in 2024; a further fourteen years to reach 9 billion in 2038; 18 years to reach 10 billion in 2056; and a farther 32 years to achieve the 11th billion in 2088.
Population growth by world region
Two hundred years ago the world population was just over one billion. Since then the number of people on the planet grew more than 7-fold to 7.7 billion in 2019. How is the globe population distributed across regions and how did it change over this catamenia of rapid global growth?
In this visualization we see historical population estimates past region from 1820 through to today. These estimates are published past the History Database of the Global Environment (HYDE) and the United Nations Population Sectionalisation from 1950 onwards.
Most people ever lived in Asia: Today it is sixty% 2 hundred years ago it was 68%. If yous desire to meet the relative distribution across the world regions in more detail yous can switch to the relative view.
The earth region that saw the fastest population growth over last two centuries was North America. The population grew 31-fold. Latin America saw the 2nd largest increment (28-fold). Over the aforementioned period the population Europe of increased 3-fold, in Africa 14-fold, and in Asia half dozen-fold.
The distribution of the world population is expected to alter significantly over the 21st century. We discuss projections of population by region here.
Population growth by country
What are the well-nigh populous countries in the world?
Over the last century, the world has seen rapid population growth. Just how are populations distributed across the world? Which countries take the most people?
In the map, we come across the estimated population of each country today. To see how this has changed since 1800, you can use the 'play' button and timeline in the lesser-left of the nautical chart. By clicking on whatever country, you tin too come across how its population has evolved over this menses.
Here we see that the superlative five about populous countries are:
(1) People's republic of china (i.44 billion)
(two) India (1.39 billion)
(3) Usa (333 million)
(4) Indonesia (276 1000000)
(5) Brazil (214 meg)
For several centuries, Communist china has been the earth's most populous country. Just not for long: it's expected that Republic of india will overtake China inside the side by side decade. You can learn more about time to come population growth by state here.
The distribution of the globe population over the last 5000 years
This series of maps shows the distribution of the world population over time. The first map – in the acme-left corner – shows the earth population in 3000 BC.
Population centers take stayed remarkably stable over this long menstruum.
Population growth rate past state and region
Global population growth peaked in the early 1960s. But how has population growth varied across the world?
There are two metrics we tin use to look at population growth rates:
(1) 'Natural population growth': this is the change in population as determined by births and deaths only. Migration flows are non counted.
(two) Population growth rate: this is the change in population every bit determined past births, deaths plus migration flows.
Both of these measures of population growth across the world are shown in the two charts. Yous tin apply the slider underneath each map to look at this modify since 1950. Clicking on any state will show a line nautical chart of its change over time, with UN projections through to 2099.
We see that there are some countries today where the natural population growth (not including migration) is slightly negative: the number of deaths exceed the number of births. When we move the fourth dimension slider underneath the map to by years, we see that this is a new phenomenon. Up until the 1970s, in that location were no countries with a negative natural population growth.
Worldwide, population growth is slowing—you tin can press the play pointer at the bottom of the chart to see the change over time.
Overall, growth rates in most countries have been going down since the 1960s. Still substantial differences exist across countries and regions.
Whilst Western Europe'southward growth rates are currently close to zip, sub-Saharan Africa'due south rates remain college than 3% — that is, still college than the peak growth rates recorded for the world at the start of the 1960s. Moreover, in many cases there has been departure in growth rates. For case, while India and Nigeria had like growth rates in 1960 (around two%), they took very unlike paths in the following years and thus currently accept populations that abound at very different rates (about 0.98% for India compared to 2.53% for Nigeria).
Ii centuries of rapid global population growth volition come to an cease
One of the big lessons from the demographic history of countries is that population explosions are temporary. For many countries the demographic transition has already ended, and as the global fertility rate has now halved nosotros know that the world as a whole is approaching the end of rapid population growth.
This visualization presents this big overview of the global demographic transition – with the 2019 information release from the United nations Population Division.
As we explore at the starting time of the entry on population growth, the global population grew only very slowly up to 1700 – only 0.04% per year. In the many millennia up to that point in history very loftier mortality of children counteracted high fertility. The world was in the outset phase of the demographic transition.
Once health improved and mortality declined things inverse quickly. Particularly over the course of the 20th century: Over the terminal 100 years global population more quadrupled. Every bit we run into in the chart, the ascent of the global population got steeper and steeper and you have just lived through the steepest increase of that curve. This also means that your existence is a tiny part of the reason why that curve is so steep.
The 7-fold increase of the earth population over the grade of 2 centuries amplified humanity's impact on the natural environment. To provide infinite, food, and resource for a big world population in a mode that is sustainable into the distant hereafter is without question one of the large, serious challenges for our generation. We should not make the fault of underestimating the chore alee of united states. Aye, I expect new generations to contribute, but for now it is upon us to provide for them. Population growth is still fast: Every twelvemonth 140 one thousand thousand are born and 58 1000000 die – the difference is the number of people that nosotros add to the world population in a yr: 82 million.
Where do nosotros get from here?
In ruby-red y'all see the annual population growth rate (that is, the percentage change in population per year) of the global population. It peaked around half a century ago. Peak population growth was reached in 1968 with an annual growth of 2.1%. Since then the increase of the world population has slowed and today grows by just over 1% per yr. This slowdown of population growth was not only predictable, merely predicted. Just every bit expected by demographers (here), the globe as a whole is experiencing the closing of a massive demographic transition.
This chart also shows how the United nations envision the slow ending of the global demographic transition. Every bit population growth continues to decline, the curve representing the earth population is getting less and less steep. By the cease of the century – when global population growth will have fallen to 0.one% according to the Un's project – the world will be very close to the cease of the demographic transition. Information technology is hard to know the population dynamics beyond 2100; information technology will depend upon the fertility charge per unit and as we discuss in our entry on fertility rates hither fertility is first falling with evolution – and and so ascent with development. The question will exist whether information technology volition ascension to a higher place an average 2 children per woman.
The world enters the final phase of the demographic transition and this means we volition not repeat the past. The global population has quadrupled over the course of the 20th century, but it will non double anymore over the course of this century.
The world population volition achieve a size, which compared to humanity's history, will be boggling; if the UN projections are accurate (they have a practiced track tape), the world population will have increased more than 10-fold over the span of 250 years.
We are on the way to a new residual. The large global demographic transition that the globe entered more than two centuries agone is so coming to an cease: This new equilibrium is dissimilar from the one in the by when it was the very high mortality that kept population growth in check. In the new balance it will exist low fertility that keeps population changes small.
The past future of the global age structure
In 1950 there were ii.5 billion people on the planet. At present in 2019, in that location are vii.7 billion. By the end of the century the UN expects a global population of xi.two billion. This visualization of the population pyramid makes it possible to empathise this enormous global transformation.
Population pyramids visualize the demographic structure of a population. The width represents the size of the population of a given age; women on the right and men to the left. The lesser layer represents the number of newborns and above it y'all discover the numbers of older cohorts. Represented in this way the population structure of societies with loftier bloodshed rates resembled a pyramid – this is how this famous blazon of visualization got its name.
In the darkest blue y'all meet the pyramid that represents the structure of the earth population in 1950. Two factors are responsible for the pyramid shape in 1950: An increasing number of births broadened the base layer of the population pyramid and a continuously high risk of death throughout life is evident by the pyramid narrowing towards the top. There were many newborns relative to the number of people at older ages.
The narrowing of the pyramid simply higher up the base of operations is testimony to the fact that more 1-in-five children born in 1950 died before they reached the age of 5.5
Through shades of blue and green the same visualization shows the population construction over the last decades up to 2018. You lot see that in each subsequent decade the population pyramid was fatter than before – in each decade more people of all ages were added to the earth population.
If you await at the dark-green pyramid for 2018 y'all see that the narrowing above the base is much less strong than back in 1950; the child mortality rate fell from ane-in-5 in 1950 to fewer than 1-in-20 today.
In comparing 1950 and 2018 we see that the number of children born has increased – 97 million in 1950 to 143 million today – and that the mortality of children decreased at the same fourth dimension. If you now compare the base of operations of the pyramid in 2018 with the projection for 2100 you see that the coming decades will non resemble the by: According to the projections there will be fewer children born at the end of this century than today. The base of the time to come population structure is narrower.
We are at a turning point in global population history. Between 1950 and today, it was a widening of the unabridged pyramid – an increment of the number of children – that was responsible for the increment of the globe population. From now on is not a widening of the base, only a 'fill up' of the population above the base: the number of children volition barely increment then first to reject, merely the number of people of working historic period and old age volition increase very substantially. Equally global wellness is improving and mortality is falling, the people alive today are expected to live longer than any generation before us.
At a state level "peak kid" is oftentimes followed past a time in which the state benefits from a "demographic dividend" when the proportion of the dependent young generation falls and the share of the population in working age increases.7
This is now happening at a global scale. For every child younger than 15 there were 1.8 people in working-age (15 to 64) in 1950; today there are 2.five; and by the stop of the century there will be 3.4.8
Richer countries have benefited from this transition in the last decades and are now facing the demographic problem of an increasingly larger share of retired people that are non contributing to the labor marketplace. In the coming decades it will be the poorer countries that can benefit from this demographic dividend.
The change from 1950 to today and the projections to 2100 show a world population that is becoming healthier. When the height of the pyramid becomes wider and looks less similar a pyramid and instead becomes more box-shaped, the population lives through younger ages with very low risk of death and dies at an old historic period. The demographic structure of a healthy population at the concluding stage of the demographic transition is the box shape that we see for the entire world for 2100.
The Demography of the World Population from 1950 to 21006
How many people die and how many are born each twelvemonth?
The globe population has grown rapidly, specially over the past century: in 1900 in that location were fewer than two billion people on the planet; today at that place are seven.7 billion.
The alter in the world population is determined by two metrics: the number of babies born, and the number of people dying.
How many are born each year?
The stacked area chart shows the number of births by world region from 1950 to 2015.
In 2015, there were approximately 140 million births – 43 1000000 more than back in 1950
The line chart shows the same data, just besides includes the Un projection until the end of the century. It is possible to switch this nautical chart to any other country or globe region in the globe.
How many dice each year?
The first nautical chart shows the annual number of deaths over the same period.
In 2015 around 55 million people died. The world population therefore increased by 84 million in that year (that is an increase of 1.14%).
The line nautical chart shows the aforementioned data, but also includes the United nations projection until the cease of the century. Again it is possible to switch this chart to any other country or globe region in the world.
As the number of deaths approaches the number of births global population growth volition come to an end
How practise we expect this to change in the coming decades? What does this hateful for population growth?
Population projections testify that the yearly number of births will remain at around 140 meg per year over the coming decades. Information technology is then expected to slowly decline in the second-one-half of the century. Every bit the world population ages, the almanac number of deaths is expected to continue to increase in the coming decades until it reaches a similar almanac number equally global births towards the terminate of the century.
As the number of births is expected to slowly fall and the number of deaths to ascent the global population growth charge per unit will continue to fall. This is when the world population will stop to increment in the futurity.
Why is rapid population growth a temporary phenomenon?
The Demographic Transition
Population growth is determined by births and deaths and every country has seen very substantial changes in both: In our overview on how health has changed over the long run you lot find the data on the dramatic decline of child mortality that has been achieved in all parts of the world. And in our coverage of fertility you find the data and inquiry on how modern socio-economic changes – about importantly structural changes to the economic system and a ascent of the condition and opportunities for women – contributed to a very substantial reduction of the number of children that couples take.
But declining mortality rates and failing fertility rates alone would non explain why the population increases. If they happened at the same fourth dimension the growth rate of the population would non change in this transition. What is crucial here is the timing at which bloodshed and fertility changes.
The model that explains why rapid population growth happens is called the 'demographic transition'. It is shown in the schematic figure. It is a beautifully unproblematic model that describes the observed blueprint in countries effectually the earth and is 1 of the corking insights of census.9
The demographic transition is a sequence of five stages:
- Stage one: high mortality and high birth rates. In the long time before rapid population growth the nascence charge per unit in a population is high, but since the expiry rate is likewise high we observe no or only very modest population growth. This describes the reality through most of our history. Societies around the world remained in stage ane for many millennia as the long-run perspective on extremely tedious population growth highlighted. At this stage the population pyramid is broad at the base just since the mortality rate is high beyond all ages – and the adventure of decease is particularly loftier for children – the pyramid gets much narrower towards the top.
- Phase ii: mortality falls but nativity rates still high. In the 2d phase the health of the population slowly starts to improve and the decease rate starts to autumn. Since the health of the population has already improved, but fertility nevertheless remains equally high as before, this is the stage of the transition at which the size of the population starts to grow apace. Historically it is the exceptional time at which the extended family with many (surviving) children is mutual.
- Phase 3: mortality low and nascency rates fall. Later the nascence rate starts to fall and consequentially the charge per unit at which the population grows begins to decline likewise. Why the fertility rate falls is a question that we reply here. But to summarize the main points: When the mortality of children is not as loftier as it once was parents suit to the healthier surround and choose to take fewer children; the economy is undergoing structural changes that makes children less economically valuable; and women are empowered socially and within partnerships and have fewer children than before.
- Stage iv: bloodshed low and birth rates low. Rapid population growth comes to an cease in stage 4 as the birth rate falls to a similar level every bit the already depression bloodshed charge per unit. The population pyramid is now box shaped; as the mortality rate at young ages is now very depression the younger cohorts are at present very like in size and simply at an old age the cohorts get smaller very rapidly.
- Stage 5: mortality low and some evidence of rising fertility. The demographic transition describes changes over the grade of socio-economic modernization. What happens at a very high level of development is not a question we can answer with certainty since only few societies have reached this stage. Only we do have some practiced bear witness – which we review here – that at very high levels of evolution fertility is rising again. Not to the very high levels of pre-modern times, but to a fertility charge per unit that gets close to 2 children per adult female. What level exactly the fertility charge per unit will reach is crucial for the question of what happens to population growth in the long run. If the fertility rate stays below 2 children per woman then we will come across a decline of the population size in the long run. If indeed the fertility rate volition rise above two children per woman nosotros will see a tiresome long-run increase of the population size.
Empirical evidence for the demographic transition
Rapid population growth is a temporary phenomenon
If fertility fell in lockstep with bloodshed we would not have seen an increase in the population at all. The demographic transition works through the asynchronous timing of the two fundamental demographic changes: The pass up of the death rate is followed by the refuse of birth rates.
This pass up of the death rate followed by a reject of the birth rate is something we discover with not bad regularity and independent of the culture or faith of the population.
The nautical chart presents the empirical bear witness for the demographic transition for v very unlike countries in Europe, Latin America, Africa, and Asia. In all countries we observed the pattern of the demographic transition, start a decline of bloodshed that starts the population nail and so a decline of fertility which brings the population nail to an end. The population boom is a temporary result.
In the past the size of the population was brackish because of loftier mortality, now state after country is moving into a globe in which the population is stagnant because of low fertility.
Demographic transition in 5 countries, 1820-201010
England and Wales's demographic transition
Maybe the longest available view of the demographic transition comes from data for England and Wales. In 1981, Anthony Wrigley and Roger Schofieldxi published a major inquiry projection analyzing English language parish registers—a unique source that allowed them to trace demographic changes for the three centuries prior to country records. According to the researchers, "England is exceptionally fortunate in having several thousand parish registers that brainstorm before 1600"; collectively, with their early start and breadth of coverage, these registers form an splendid resources. As far equally we know, there is no comparable information for any other country upwards until the mid-eighteenth century (see the following department for Sweden, where recordkeeping began in 1749).
The chart shows the birth and expiry rates in England and Wales over the span of nearly 500 years. It stitches together Wrigley and Schofield'due south data for the years 1541-1861 with two other sources up to 2015 (click on the chart's 'sources' tab for details). Every bit we can see, a growing gap opens up between the nascence and death rate afterwards 1750, creating a population explosion. Effectually the 1870'due south, we begin to run into the tertiary stage of the demographic transition. As the nativity rate starts to follow the expiry rate's decline, that gap betwixt the two starts to shrink, slowing downwardly the population growth charge per unit.
Sweden'due south demographic transition
Zooming in on one of these countries, we take a expect at Sweden's demographic transition. The country's long history of population recordkeeping—starting in 1749 with their original statistical part, 'the Tabellverket' (Part of Tables)—makes information technology a particularly interesting case study of the mechanisms driving population change.
Statistics Sweden, the successor of the Tabellverket, publishes data on both deaths and births since recordkeeping began more 250 years ago. These records suggest that effectually the twelvemonth 1800, the Swedish expiry rate started falling, mainly due to improvements in health and living standards, especially for children.12
Yet while death rates were falling, nativity rates remained at a abiding pre-modern level until the 1860s. During this menstruum 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.
Changes to birth and expiry charge per unit over time around the world
The visualization presents the nascence and death rate for all countries of the globe over the terminal 5 decades. You tin see the alter over past moving the slider underneath back and forth or past pressing the "play" push button. Countries per continent can also exist highlighted by hovering and clicking on them in the legend on the right side of the chart.
Past visualising this change nosotros see how in state subsequently state the decease rate fell and the nascence charge per unit followed – countries moved to left-mitt-side first and so brutal to the bottom left corner.
Today, unlike countries straddle dissimilar stages of the model. Most adult countries accept reached phase four and accept low nativity and death rates, while developing countries continue to make their way through the stages.
How development affects population growth
In that location are ii important relationships that help explain how the level of development of a country affects its population growth rates:
- Fertility rate is the parameter which matters most for population changes – information technology is the strongest determinant;
- As a country gets richer (or 'more developed'), fertility rates tend to fall.
Combining these two relationships, nosotros would expect that as a country develops, population growth rates decline.
Generally, this is true. In the visualization, nosotros see how the population growth charge per unit has inverse for 'more adult', 'less developed' and 'least developed' countries (based on Un categorization), and how they are projected to modify through 2099.
Here we run across that population growth rates are lowest in the most adult regions – starting at just over one% in the 1950s and falling to merely 0.19% today. 'Less developed' regions peaked later, at a college growth rate (2.55%) and have declined more slowly. 'To the lowest degree developed' regions did not tiptop in growth charge per unit until the early 1990s.
Over the last two decades we have seen failing population growth rates in countries at all stages of evolution.
Population momentum
If the number of children is non growing, why is the population nevertheless increasing?
In 1965 the average woman on the planet had 5 children. fifty years afterwards this statistic – chosen the full fertility rate – has fallen to less than half. The start panel in this chart shows this fundamental modify.
The total fertility charge per unit at which a population replaces itself from one generation to the next is called thereplacement fertility charge per unit. If no children died before they grew upwardly to have children themselves the replacement fertility rate would be 2. Considering some children dice, the global replacement fertility rate is currently 2.three and therefore just slightly lower than the bodily global fertility rate. Why so is global population growth not coming to an cease yet?
The number of births per woman in the reproductive age subclass is only one of ii drivers that matter hither. The 2nd 1 is the number of women in the reproductive age bracket.
If at that place were few women in the reproductive age bracket the number of births will be depression even when the fertility rate is high. At times when an increasing share of women enter the reproductive age bracket the population tin keep growing fifty-fifty if the fertility charge per unit is falling. This is what demographers refer to as 'population momentum' and it explains why the number of children in the world will not decline equally apace as the fertility charge per unit.
The second nautical chart in this panel shows that the population growth over the concluding decades resulted in increasingly larger cohorts of women in the reproductive age bracket. Equally a result, the number of births will stay high fifty-fifty equally the number of births per adult female is falling. This is what the lesser console in the chart shows. According to the UN projections, the two drivers will abolish each other out and then that the number of births volition 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 143 million and so to decline slowly to 131 1000000 births by 2100. The coming decades will be very different from the terminal. While the annual number of births increased by 43 million since 1950 nosotros are now shut to what the late Hans Rosling chosen "the historic period of peak child" – the moment in global demographic history at which the number of children in the world stops increasing. How close we are to superlative child we looked at in a more detailed post.
Population momentum is one important driver for high population growth. Merely it of course as well matters that all of us today live much longer than our ancestors simply a few generations ago. Life expectancy is now twice as long in all globe regions.
In all of this it is of import to go on in mind that these are projections and how the future will actually play out volition depend on what we are doing today.
Population momentum is driven by the increasingly large cohorts of women in the reproductive age bracket. It's only when both the fertility charge per unit and the number of women level off that population momentum stops. And this is when global population growth volition come to an end. Hans Rosling explained it better than anyone, with the help of toilet rolls.
How does migration touch country populations?
At the global level, population changes are determined by the balance of only ii variables: the number of people built-in each yr, and the number who die.
At regional or country levels there is a third variable to consider: migration into (immigration) or migration out of (emigration) the region/land. How large of an impact does migration take on population changes across the world?
In this chart nosotros run across the annual population growth charge per unit nether ii scenarios:
- population growth charge per unit with migration – this includes the balance of births, deaths plus migration;
- a hypothetical population growth rate if at that place was cypher migration (i.e. it is based only on the residuum of births and deaths).
The instance shown here is the United States but you can explore this data for any country or region using the "change country" push button on the interactive chart.
In the U.s. we run into that since the early on 1950s, migration into the USA has exceeded emigration out of the country. This means net migration has been positive, and resulted in a college population growth rate than would have occurred in the scenario with zero migration. In 2015, for case, the bodily population growth rate was 0.68%. With zero migration, this would have been 0.38%.
This is also truthful for most countries beyond Europe. In fact, population growth would take been negative (i.e. the population would have been in refuse) in Europe since the early 1990s without migration. In 2015, the European population increased by 0.17%; with no migration, it would have decreased by 0.02%.
The opposite is of form truthful for countries where emigration (out of the state) is college than immigration. Take Nepal as an example: in the mid-1990s its actual population growth rate has been lower than it would have been in the absenteeism of migration. In 2015, its growth rate was 0.66%. With zero migration information technology would have been 1.43%.
Population age structure
This article previously covered aspects of population historic period structure; yous now find this material in our entry on Age Construction.
The track record of the United nations projections
How much do population estimates differ?
It'due south expected that sources will differ in their projections for future populations: although the Un projections to engagement accept been remarkably authentic, they are based on a number of assumptions regarding the change in fertility, bloodshed and migration over fourth dimension.
But historic and current population estimates between sources are also not identical. The United nations Population Division publishes the almost-widely adopted figures, but in that location are a few other key information sources including the U.s. Demography Bureau and Population Reference Bureau (PRB).
How exercise these sources compare? In the chart we see the comparing between the UN (shown in blood-red) and US Demography Bureau (in bluish) estimates globally and by region. Global estimates have varied by around 0.v-ane.5%.
The largest variation comes from estimates of Asia, Africa and Latin America – where census data and underlying data sources will be less consummate and lower quality. This ways some estimation and judgement is necessary from expert demographers within each system. Information technology'southward in this process of expert interpretation that most of the departure will arise.
A comparison of 2015 estimates betwixt the UN, United states Census Bureau and PBS are shown in this table.13 , 14 , 15
Here we run into that the UN and PBS estimates are very similar at around 7.34 to 7.35 billion. United states Census Bureau estimates are around ane-2% lower at 7.25 billion.
With known gaps in census information and underlying sources, it'south recommended that population estimates are given to only 3 to 4 meaning figures. Quoting them to more gives a false sense of precision. Beyond the sources, nosotros can say that there were 7.25 to 7.four billion people in the world in 2015.
Click to open interactive version
| Source | Earth population (2015) |
|---|---|
| United nations Population Sectionalisation (2017 Revision) | 7,383,009,000 |
| The states Census Agency (2017) | seven,247,892,788 |
| Population Reference Bureau (2015) | vii,336,435,000 |
How are population revisions created?
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 exist consistent and comparable within and across countries and fourth dimension.
The methodology used by the Un to produce their estimates and projections is explained extensively in the Earth Population Prospects' Methodology Report.
In short, estimates of the population in the past (i.e. 1950-2015) are produced by starting with a base population for ane July 1950 and calculating subsequent populations based on the components that drive population change (fertility, mortality, and international migration). The estimates of these components are taken directly from national statistical sources or—where but fractional or poor-quality information exists—are estimated by the Population Division staff. Population counts from periodic censuses are used as benchmarks. This adding is called the "cohort-component" method because it estimates the change in population by age and sex (cohort) on the basis of the iii afore-mentioned demographic components: fertility, mortality, and international migration.
One of the main implications of using the cohort-component method is that it sometimes leads to marked inconsistencies with official state statistics. The process of 'revising' the estimates involves incorporating new information about the demography of each land.
What is the quality of birth and death registration?
The standard methodology used for producing population estimates relies on the so-called cohort model. Providing loftier-quality estimates requires reliable and up-to-engagement census data.
Crucial to population estimates are nascency and bloodshed rates: this census data therefore relies on nascency registration and expiry reporting.
The two maps prove the abyss of nascency and death reporting across the earth. Many countries, peculiarly those in the least developed regions of the world, have limited census information.
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 aforementioned region with a socio-economical profile considered close to the country in question.
Estimates of ancient population
Equally discussed in the previous section, there are a number of studies providing celebrated population data. The most usually cited source is McEvedy and Jones (1978).
McEvedy and Jones (1978)
- Information Source: McEvedy, Colin and Richard Jones (1978), "Atlas of World Population History," Facts on File, New York, pp. 342-351; relying on archeological and anthropological evidence, too equally historical documents such as Roman and Chinese censuses
- Description of bachelor measures: Population
- Time span: 400BCE-2,000CE
- Geographical coverage: Global by country and regions
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, Thousand. K., Beusen, A., & Janssen, P. (2010). Long-term dynamic modelling of global population and built-up area in a spatially explicit manner: HYDE 3.1. The Holocene.
History Database of the Global Environment (HYDE)
- Information Source: History Database of the Global Environment projection, using estimates from McEvedy and Jones (1978), Livi-Bacci (2007)16, Maddison (2001)17, and Denevan (1992)18
The information from the HYDE projection is in turn the ground for the population series published by the 'Clio-Infra' projection
Clio-Infra
- Data Source: HYDE project and UN Population Division
- Clarification of available measures: Population
- Time span: 1,500-2,000CE
- Geographical coverage: Global by country
- Link: www.clio-infra.eu/
Estimates of population in recent history and projections
UN Population Database
- Information Source: United nations Population Sectionalisation based on 'accomplice-component' framework by demographic trends (run across Data Quality section)
- Description of available measures:
◦ Population, by Five-Year Age Grouping and Sex
◦ Population Sex Ratio (males per 100 females)
◦ Median Age
◦ Population Growth Per Year
◦ Crude Nascence Rate
◦ Crude Death Rate
◦ Net Reproduction Charge per unit
◦ Full Fertility Rate
◦ Life Expectancy at Nativity by Sex
◦ Internet Migration Rate
◦ Sex ratio at nascence
◦ Births
◦ Births by Age-grouping of Female parent
◦ Historic period-specific Fertility Rates
◦ Women Aged 15-49
◦ Deaths by Sexual activity
◦ Babe Mortality
◦ Mortality Nether Age 5
◦ Dependency Ratios
◦ Population past Historic period: 0-iv, 0-14, five-14, xv-24, fifteen-59, 15-64, 60+, 65+, lxxx+ - Time span: 1950-2015
- Geographical coverage: Global by country
- Link: http://esa.united nations.org/unpd/wpp/
Gridded Population of the World (GPW)
- Information Source: Heart for International Earth Scientific discipline Information Network (CIESIN), published by the Socioeconomic Data and Applications Center (SDAC) based on census data
- Clarification of available measures: Population
- Time span: 1990-2010
- Geographical coverage: Global at a two.5 arc-infinitesimal spatial resolution
- Link: http://sedac.ciesin.columbia.edu/data/collection/gpw-v3
- Notes: Within the CIESIN, the Anthropogenic Biomes map the distribution of the world population at unlike points in time: 1700, 1800, 1900, 2000. These maps focus on the varying impact of humans on the surround.
LandScan
- Data Publisher: University of Iowa (originally adult by the Oak Ridge National Laboratory (ORNL) for the Department of Defence force, U.Southward.)
- Data Source: Annual mid-year national population estimates from the Geographic Studies Co-operative, US Bureau of Census
- Description of available measures: Population and 'ambient population' (a mensurate of person-hours accounting for varying presence throughout the day in commercial areas)
- Time span: 1998-2012, merely authors warn of inter-temporal comparability issues
- Geographical coverage: Global at xxx arc-second grid spatial resolution (highest population resolution available)
- Link: http://sedac.ciesin.columbia.edu/data/collection/gpw-v3
World Development Indicators
- Data Publisher: Globe Bank
- Data Source: UN Population Division
- Description of bachelor measures: Population growth (almanac %)
- Time span: 1981-2015
- Geographical coverage: Global past country
- Link: http://information.worldbank.org/indicator/
Compilations of demography data and other sources
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.populstat.info.
The Minnesota Population Center publishes various loftier-quality datasets based on census data beginning in 1790. At the time of writing this source was online at www.popular.umn.edu/index.php. It focuses on North America and Europe.
The Data & Information Services Center (DISC) Archive at University of Wisconsin-Madison provides access to census data and population datasets (mostly for the Americas). At the time of writing this source was online at http://www.disc.wisc.edu.
The International Database published by the U.South. Census Bureau provides data for the time 1950-2100. At the time of writing this source was online at https://www.census.gov/data-tools/demo/idb/informationGateway.php.
The Atlas of the Biosphere publishes data on Population Density. At the time of writing this source was online at www.sage.wisc.edu/atlas/maps.
Where in the World Do Most Teen Have Babies
Source: https://ourworldindata.org/world-population-growth