Over the next several days, I will be posting some basic terms associated with demography and demographics. Here are a few:
Cohort: A group of people having some common feature who are measured in some fashion over a period of time
Demographics: The statistical data derived from measuring human populations
Demography: The study and measurement of human populations through statistics
Population: The total sum of persons in a given group. A population can be a wide variety of groups, large and small.
The largest human population, of course, is the sum total of all human beings who are currently alive. The United States, of course, has a total population, as does Baldwin County, Alabama. All American women from ages 15 to 44 make up another population. If fact, we consider these women to be a population in its prime childbearing years.
Population Change: The net amount of positive or negative change, in a given amount of time (often a year), to a given population. Population change can be either population growth (positive change) or population decline (negative change).
As an equation, population change can be expressed as:
(Births –Deaths) + (Immigration –Emigration) = Population Change.