Population Growth & Development
Birthrate See crude birthrate.
Crude birthrate The number of children born alive each year per 1,000 population (a crude birthrate of 20 per 1,000 is the same as a 2% increase). See also fertility rate and death rate.
Death rate The yearly number of deaths per 1,000 population - an annual crude death rate of 15 per 1,000 would involve 1.5% of the population. See also crude birthrate and infant mortality rate.
Fertility rate The yearly number of children born alive per 1,000 women within the childbearing age bracket (normally between the ages of 15 and 49 years). See also crude birthrate. The total fertility rate (TFR) is the number of children that would be born to a woman if she were to live to the end of her childbearing years and bear children at each age in accordance with the prevailing age-specific fertility rates.
Hidden momentum of population growth A dynamic latent process of population increase that continues even after a fall in birthrates because of a large youthful population that widens the populationís parent base. Fewer children per couple in the succeeding few generations will not mean a smaller or stable population size because at the same time there will be a much larger number of childbearing couples. Hence a given population will not stabilize until after two or three generations.
Infant mortality rate Deaths among children between birth and 1 year of age per 1,000 live births.
Life expectancy at birth The number of years newborn children would live if subject to the mortality risks prevailing for the cross section of population at the time of their birth. See also crude birthrate.
Mortality See death rate.
Net international migration Excess of persons migrating into a country over those who emigrate from that country. See brain drain.
Population pyramid Graphical depiction of the age structure of the population, with age cohorts plotted on the vertical axis and numbers of males and females in each cohort on the horizontal axis.
Demographic transition The phasing-out process of population growth rates from a virtually stagnant growth stage characterized by high birthrates and death rates, through a rapid-growth stage with high birthrates and low death rates, to a stable, low-growth stage in which both birth and death rates are low.
Dependency burden The proportion of the total population aged 0 to 15 and 65+, which is considered economically unproductive and therefore not counted in the labor force. In many LDCs, the population under the age of 15 accounts for almost half of the total population, thus posing a burden to the generally small productive labor force and to the government, which has to allocate resources on such things as education, public health, and housing for the consumption of people who donít contribute to production.
Family-planning programs Public programs designed to help parents plan and regulate their family size in accordance with their ability to support a family. The program usually includes supplying contraceptives to the adult population, education on the use of birth control devices, mass-media propaganda on benefits derived from smaller families, and pre- and postnatal health care for mothers.
Malthusian population trap An inevitable population level envisaged by Thomas Malthus (1766- 1834) at which population increase was bound to stop because after that level, life-sustaining resources, which increase at an arithmetic rate, would be insufficient to support human population, which increases at a geometric rate. Consequently, people would die of starvation, disease, wars, etc. The Malthusian population trap therefore represents the maximum population size that can be supported by the available resources.
Microeconomic theory of fertility An extension of the theory of consumer behavior of individual couples. The central proposition of this theory is that family formation has costs and benefits and hence the size of families formed will depend on these costs and benefits. If the costs of family formation are high relative to its benefits, the rates at which couples will decide to bring forth children will decline, and vice versa. See also opportunity cost of a womanís time, fertility rate, and crude birthrate.
Opportunity cost of a womanís time Real or monetary wages or profits that a woman sacrifices by deciding to stay home and raise children instead of working for a wage or engaging in profit-making self-employment activities. The higher the opportunity cost of a womanís time involved in rearing children, the more unwilling she will be to have more children, at least in terms of the microeconomic theory of fertility.
Positive checks In Malthusian theory, the effects of war, disease, and famine in controlling excess population growth.
Preventive checks In Malthusian theory, the effects of delayed marriage, sexual abstinence, and birth control in controlling excess population growth.
Youth dependency ratio The proportion of young people under age 15 to the working population aged 16-64 in a country. See also dependency burden.