China's one-child policy was part of a birth planning program designed to control the size of its population. Distinct from the family planning policies of most other countries, it set a limit on the number of children parents could have, the world's most extreme example of population planning. It was introduced in 1979, modified in the mid 1980s to allow rural parents a second child if the first was a daughter, and then lasted three more decades before being eliminated at the end of 2015. The policy also allowed exceptions for some other groups, including ethnic minorities. The term one-child policy is thus a misnomer, because for nearly 30 of the 36 years that it existed (1979–2015) about half of all parents in China were allowed to have a second child.
Demography is the statistical study of populations, especially human beings.
Human reproduction planning is the practice of intentionally controlling the rate of growth of a human population. Historically, human population planning has been implemented with the goal of increasing the rate of human population growth. However, in the period from the 1950s to the 1980s, concerns about global population growth and its effects on poverty, environmental degradation and political stability led to efforts to reduce human population growth rates. More recently, some countries, such as China, Iran, and Spain, have begun efforts to increase their birth rates once again. While population planning can involve measures that improve people's lives by giving them greater control of their reproduction, a few programs, most notably the Chinese government's "one-child policy and two-child policy", have resorted to coercive measures.
In mathematics, a ratio is a relationship between two numbers indicating how many times the first number contains the second. For example, if a bowl of fruit contains eight oranges and six lemons, then the ratio of oranges to lemons is eight to six. Similarly, the ratio of lemons to oranges is 6:8 and the ratio of oranges to the total amount of fruit is 8:14.
The phenomenon and theory of the demographic transition refers to the historical shift in demographics from high birth rates and high infant death rates in societies with minimal technology, education and economic development, to demographics of low birth rates and low death rates in societies with advanced technology, education and economic development, as well as the stages between these two scenarios. Although this shift has occurred many industrialized countries, the theory and model are frequently imprecise when applied to individual countries due to specific social, political and economic factors affecting particular populations.
Family planning services are defined as "educational, comprehensive medical or social activities which enable individuals, including minors, to determine freely the number and spacing of their children and to select the means by which this may be achieved". Family planning may involve consideration of the number of children a woman wishes to have, including the choice to have no children, as well as the age at which she wishes to have them. These matters are influenced by external factors such as marital situation, career considerations, financial position, and any disabilities that may affect their ability to have children and raise them. If sexually active, family planning may involve the use of contraception and other techniques to control the timing of reproduction.
The birth rate is the total number of live births per 1,000 in a population in a year or period. The rate of births in a population is calculated in several ways: live births from a universal registration system for births, deaths, and marriages; population counts from a census, and estimation through specialized demographic techniques. The birth rate are used to calculate population growth.
In economics, geography, demography and sociology, the dependency ratio is an age-population ratio of those typically not in the labor force and those typically in the labor force. It is used to measure the pressure on the productive population.
The total fertility rate (TFR), sometimes also called the fertility rate, absolute/potential natality, period total fertility rate (PTFR), or total period fertility rate (TPFR) of a population is the average number of children that would be born to a woman over her lifetime if:
- She was to experience the exact current age-specific fertility rates (ASFRs) through her lifetime, and
- She was to survive from birth to the end of her reproductive life.
Sub-replacement fertility is a total fertility rate (TFR) that leads to each new generation being less populous than the older is any rate below approximately 2.1 children born per woman, but the threshold can be as high as 3.4 in some developing countries because of higher mortality rates. Taken globally, the total fertility rate at replacement was 2.33 children per woman in 2003. This can be "translated" as 2 children per woman to replace the parents, plus a "third of a child" to make up for the higher probability of boys born and mortality prior to the end of a person's fertile life.
In statistics, the coefficient of determination, denoted R2 or r2 and pronounced "R squared", is the proportion of the variance in the dependent variable that is predictable from the independent variable(s).
Population momentum is a consequence of the demographic transition. Population momentum explains why a population will continue to grow even if the fertility rate, the number of children per woman, declines. Population momentum occurs because it is not only the number of children per woman that determine population growth, but also the number of women in reproductive age. Eventually, when the fertility rate reaches the replacement rate and the population size of women in the reproductive age bracket stabilizes, the population achieves equilibrium and population momentum comes to an end. Population momentum is defined as the ratio of the size of the population at that new equilibrium level to the size of the initial population. Population momentum usually occurs in populations that are growing.
Advanced maternal age, in a broad sense, is the instance of a woman being of an older age at a stage of reproduction, although there are various definitions of specific age and stage of reproduction. The variability in definitions is in part explained by the effects of increasing age occurring as a continuum rather than as a threshold effect.
Demographic dividend, as defined by the United Nations Population Fund (UNFPA) means, "the economic growth potential that can result from shifts in a population’s age structure, mainly when the share of the working-age population is larger than the non-working-age share of the population ". In other words, it is “a boost in economic productivity that occurs when there are growing numbers of people in the workforce relative to the number of dependents.” UNFPA stated that, “A country with both increasing numbers of young people and declining fertility has the potential to reap a demographic dividend.
The middle of the 20th century was marked by a significant and persistent increase in fertility rates in many countries of the world, especially in the West, resulting in the famous baby boomer generation. Although the baby boom traditionally considered to be the post-war phenomenon started immediately after World War II, some demographers place it earlier, at the increase of births during the war or in the late 1930s.
A two-child policy is a government-imposed limit of two children allowed per family or the payment of government subsidies only to the first two children. It has previously been used in Vietnam. In British Hong Kong in the 1970s, citizens were also highly encouraged to have two children as a limit, and it was used as part of the region's family planning strategies. Since 2016, it has been implemented in China, replacing the country's previous one-child policy.
Family planning in India is based on efforts largely sponsored by the Indian government. From 1965–2009, contraceptive usage has more than tripled and the fertility rate has more than halved, but the national fertility rate remains high, causing concern for long-term population growth. India adds up to 1,000,000 people to its population every 20 days. Extensive family planning has become a priority in an effort to curb the projected population of two billion by the end of the twenty-first century.
Population planning in Singapore spans two distinct phases: first to slow and reverse the boom in births that started after World War II; and second, from the 1980s onwards, to encourage parents to have more children because birth numbers had fallen below replacement levels.
Fertility factors are determinants of the number of children that an individual is likely to have. Fertility factors are mostly positive or negative correlations without certain causations.
