Reasons for population studies

There are many good reasons for studying population statistics. The most general of these is the advancement of science: finding out what happens, formulating theories as to why it occurs and testing these theories against the course of events. Secondly there is practical value in measuring population growth so as to be able to plan ahead for satisfying man's needs throughout life -food, clothing, shelter and other necessities. Thirdly there is the aspect of the subject that is sometimes called ‘political arithmetic’ –the name that some of the pioneers of demography used to indicate the nature of their interest in population: demographic data may facilitate the making of arrangements for the ascertainment of people's views on important topical questions, the election of representative governing bodies, the collection of taxes, the planning and conduct of industry and commerce, the provision of social services, the maintenance of health and the preservation of law and order. Such data may also help to give some guide to the probable outcome of such activities. The changing balance of young and old people, for instance, affects government expenditure on matters such as education, child welfare, housing and pensions, and the more the demands of the future can be foreseen, the better the planning can be.

Finally, some governments have developed or are developing policies involving legislation or other action designed to have an influence (or to eliminate certain influences) upon the size, trend or distribution of population; and, even where governments have not gone this far, many people believe that they should do so.