Demography literally translated from the Greek term means a description of people. On the other hand, the United Nations (UN) Demographic Dictionary describes demography as the scientific study of human populations primarily with respect to size, their, structure and their development.
Demography therefore is concerned with the current size and characteristics of human populations, how they were attained, and how they are changing. Changes in the characteristics of human populations is governed by the three main Population Processes: Fertility, Mortality and Migration. In turn, when these processes act, there are corresponding Population Outcomes which include changes in Population Size, Age and Sex Structure, and Spatial Organization.
While these main processes are the primary concern of demographers, it proves invaluable should these things not be detached from their relationships with other disiplines. As such, demography draws and contributes to the other fields of sciences ranging from Health and Medicine and Teletraffic to the social sciences such as Sociology, Anthropology and Political Science.
What do Demographers do?
Demography includes the study of human populations by statistical methods. Demographers basically deal with the measurements of the number of people in each region of the country:
- being born (hatch)
- living (match)
- dying (dispatch!)
Demographers also have to measure
- marriage rates
- ageing rate
- mortality rate
Finally demographers measure migrations:
- internal migration = urbanization (or rural-urban migration)
- external migration ( --> immigration and emigration --> ).
Data from statistical censuses are the basic inputs, but have to be augmented with input from questionnaires and surveys. The trends are extrapolated (projected forwards).
The practical purpose is that the output forms the basis for the prediction of number of customers for public and private services and products.