Population momentum
Encyclopedia
Population momentum refers to population growth
at the national level which would occur even if levels of childbearing immediately declined to replacement level. For countries with above-replacement fertility
(greater than 2.1 children per woman), population
momentum represents natural increase to the population. For below-replacement countries, momentum corresponds to a population decline. Momentum occurs because older cohorts differ in absolute size from those cohorts currently bearing children, which impacts the immediate birth and death rates in the population which determine the intrinsic rate of growth. Formal demographers refer to population momentum as the size of the resulting stationary-equivalent population relative to the current size of the population. Population momentum has implications for population policy for a number of reasons. First with respect to high-fertility countries in the developing world, population momentum instructs us that these countries will continue to grow despite large and rapid declines in fertility. Second with respect to lowest-low fertility countries in Europe, momentum implies that these countries may experience population decline even if they bring their fertility levels up to replacement. In fact, population momentum can become negative if fertility rates are under replacement for long enough; in coming decades, for example, some Eastern European countries would show population shrinkage even if their birth rates recovered to replacement level. Finally, population momentum shows us that replacement level fertility is a long term concept rather than an indication of current population growth rates. Depending on the extant age structure, a fertility rate of 2 children per woman may correspond to either short-term growth or decline.
Population growth
Population growth is the change in a population over time, and can be quantified as the change in the number of individuals of any species in a population using "per unit time" for measurement....
at the national level which would occur even if levels of childbearing immediately declined to replacement level. For countries with above-replacement fertility
Fertility
Fertility is the natural capability of producing offsprings. As a measure, "fertility rate" is the number of children born per couple, person or population. Fertility differs from fecundity, which is defined as the potential for reproduction...
(greater than 2.1 children per woman), population
Population
A population is all the organisms that both belong to the same group or species and live in the same geographical area. The area that is used to define a sexual population is such that inter-breeding is possible between any pair within the area and more probable than cross-breeding with individuals...
momentum represents natural increase to the population. For below-replacement countries, momentum corresponds to a population decline. Momentum occurs because older cohorts differ in absolute size from those cohorts currently bearing children, which impacts the immediate birth and death rates in the population which determine the intrinsic rate of growth. Formal demographers refer to population momentum as the size of the resulting stationary-equivalent population relative to the current size of the population. Population momentum has implications for population policy for a number of reasons. First with respect to high-fertility countries in the developing world, population momentum instructs us that these countries will continue to grow despite large and rapid declines in fertility. Second with respect to lowest-low fertility countries in Europe, momentum implies that these countries may experience population decline even if they bring their fertility levels up to replacement. In fact, population momentum can become negative if fertility rates are under replacement for long enough; in coming decades, for example, some Eastern European countries would show population shrinkage even if their birth rates recovered to replacement level. Finally, population momentum shows us that replacement level fertility is a long term concept rather than an indication of current population growth rates. Depending on the extant age structure, a fertility rate of 2 children per woman may correspond to either short-term growth or decline.
Countries with a Population momentum
The following list are countries that maintain growth despite a fertility rate of under 2.1. However, some of these countries also maintain growth due to immigration.- AustraliaAustraliaAustralia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
- SpainSpainSpain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
- CanadaCanadaCanada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
- United States
- NorwayNorwayNorway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...
- FinlandFinlandFinland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...
- SwedenSwedenSweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
- DenmarkDenmarkDenmark is a Scandinavian country in Northern Europe. The countries of Denmark and Greenland, as well as the Faroe Islands, constitute the Kingdom of Denmark . It is the southernmost of the Nordic countries, southwest of Sweden and south of Norway, and bordered to the south by Germany. Denmark...
- United KingdomUnited KingdomThe United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
- BelgiumBelgiumBelgium , officially the Kingdom of Belgium, is a federal state in Western Europe. It is a founding member of the European Union and hosts the EU's headquarters, and those of several other major international organisations such as NATO.Belgium is also a member of, or affiliated to, many...
- NetherlandsNetherlandsThe Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...
- LuxembourgLuxembourgLuxembourg , officially the Grand Duchy of Luxembourg , is a landlocked country in western Europe, bordered by Belgium, France, and Germany. It has two principal regions: the Oesling in the North as part of the Ardennes massif, and the Gutland in the south...
- FranceFranceThe French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
- SwitzerlandSwitzerlandSwitzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....
- AustriaAustriaAustria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...
- PortugalPortugalPortugal , officially the Portuguese Republic is a country situated in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the...
- SlovakiaSlovakiaThe Slovak Republic is a landlocked state in Central Europe. It has a population of over five million and an area of about . Slovakia is bordered by the Czech Republic and Austria to the west, Poland to the north, Ukraine to the east and Hungary to the south...
- SerbiaSerbiaSerbia , officially the Republic of Serbia , is a landlocked country located at the crossroads of Central and Southeast Europe, covering the southern part of the Carpathian basin and the central part of the Balkans...
- Bosnia and HerzegovinaBosnia and HerzegovinaBosnia and Herzegovina , sometimes called Bosnia-Herzegovina or simply Bosnia, is a country in Southern Europe, on the Balkan Peninsula. Bordered by Croatia to the north, west and south, Serbia to the east, and Montenegro to the southeast, Bosnia and Herzegovina is almost landlocked, except for the...
- Republic of MacedoniaRepublic of MacedoniaMacedonia , officially the Republic of Macedonia , is a country located in the central Balkan peninsula in Southeast Europe. It is one of the successor states of the former Yugoslavia, from which it declared independence in 1991...
- AlbaniaAlbaniaAlbania , officially known as the Republic of Albania , is a country in Southeastern Europe, in the Balkans region. It is bordered by Montenegro to the northwest, Kosovo to the northeast, the Republic of Macedonia to the east and Greece to the south and southeast. It has a coast on the Adriatic Sea...
- GreeceGreeceGreece , officially the Hellenic Republic , and historically Hellas or the Republic of Greece in English, is a country in southeastern Europe....
- CyprusCyprusCyprus , officially the Republic of Cyprus , is a Eurasian island country, member of the European Union, in the Eastern Mediterranean, east of Greece, south of Turkey, west of Syria and north of Egypt. It is the third largest island in the Mediterranean Sea.The earliest known human activity on the...
- ChinaPeople's Republic of ChinaChina , officially the People's Republic of China , is the most populous country in the world, with over 1.3 billion citizens. Located in East Asia, the country covers approximately 9.6 million square kilometres...
- South KoreaSouth KoreaThe Republic of Korea , , is a sovereign state in East Asia, located on the southern portion of the Korean Peninsula. It is neighbored by the People's Republic of China to the west, Japan to the east, North Korea to the north, and the East China Sea and Republic of China to the south...
- TaiwanRepublic of ChinaThe Republic of China , commonly known as Taiwan , is a unitary sovereign state located in East Asia. Originally based in mainland China, the Republic of China currently governs the island of Taiwan , which forms over 99% of its current territory, as well as Penghu, Kinmen, Matsu and other minor...
- ThailandThailandThailand , officially the Kingdom of Thailand , formerly known as Siam , is a country located at the centre of the Indochina peninsula and Southeast Asia. It is bordered to the north by Burma and Laos, to the east by Laos and Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the...
- IranIranIran , officially the Islamic Republic of Iran , is a country in Southern and Western Asia. The name "Iran" has been in use natively since the Sassanian era and came into use internationally in 1935, before which the country was known to the Western world as Persia...
- BrazilBrazilBrazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...