The Population Census provides the fullest and most reliable picture of the country's population and its characteristics at the “Determinant Date” (a particular point in time to which the census relates). In the census, data is collected at a specified time from the entire population; in contrast to other surveys, in which information is collected from only a small part of the residents, and from that conclusions are reached regarding the general population.
The Population Census is unique in that it provides the possibility of examining small and special population groups, and acquiring information on small geographic units (localities or dwelling units and neighbourhoods). In most countries population census is carried once in every ten years. Like in Tanzania to date, the census was carried out five times, at first it was conducted in 1910 and then after the national independence it was carried out in 1967, 1978, 1988 and 2002 plus the current one of August, 2012 (http://www.nbs.go.tz/sensa2012/).
The census is one of the most important sources of information that provides a basis for the official statistics of the country. A population census, by the definition customary today, is a complete process of collection, reception, assessment, analysis, publication and distribution of demographic, economic and social data, which relate, at a given moment in time, to all the residents of a country or of a well-defined partial geographic area; as reflected in the Population and Housing Censuses Handbook of the UN, 1992.
Types of population Census
There are two main types of population census and they are:
1. Defacto Population census: This is the type of population census which involves the counting of only those who are present physically during census. In this group, only those who are present physically or seen are counted.
2. De jure population census: This is the type of population census which involves the counting of people who have been permanent residents of a specific area. It does not matter whether the person is present of not. This is population census commonly referred to as counting by proxy.
Stages of expediting the census, conducting a census is a most complex undertaking, and therefore careful planning of each detail is required in the census process - in the methodological, contents and technological fields, as well as the organizational and administrative aspects. Great importance and a special emphasis are placed on planning and prior preparation when planning the execution of a census, preparation that includes many tests and repeated trials.
Census activities can be divided into three main stages:
1. The planning stage.
2. The stage of data collection.
3. The stage of producing the results.
The first stage - planning and preparation towards data collection, this stage is critical. During this stage, and especially at its beginning, the purpose and methodology of the census are determined, the main strategical decisions are made, and intermediate goals are defined, whose achievement makes the realization of the final goals possible. A great emphasis is put on the development of methods and means designed to achieve the goals of the census.
The second stage - data collection, during this stage data on the census population is collected, by direct contact with the residents and/or through information found in administrative resources. This is the most intensive stage, especially if the data collection in the field is extensive. This stage requires complex logistic preparation and is conducted in a relatively short period of time (normally few weeks to several months). In order to achieve good results during the process of collecting data from the population and a high level of quality of the data collected, there is a need for both a publicity campaign to enlist the cooperation and participation of the public at its fullest, as well as a high level of skills in the field operation is required.
The third stage - producing the results; including receipt, processing, estimation, analysis, publication and distribution of the census data, this stage is long and complex, from a professional viewpoint. During this stage three major activities occur simultaneously: Preparation of the final file of the census data (including receipt of the information, identification and correction of errors, editing of the data collected, imputation of missing data and calculation of estimates). Production of products by which the findings of the census are published and distributed, in the form of various statistical summaries and their analyses, or as files of anonymous individual records. Conducting activities of data assessment, from which a picture results of the extent of coverage of the population and the quality of the information produced.
Importance or Reasons of Population Census
The importance or reasons for conducting a population census as quoted from (Funom Makama in Ezine Articles) include: "aiding the government to know the number of people living in the country and the structure of the population; helping in the determination of taxable adults so as to know the amount of revenue expected from that sector; enabling the country to forecast her future economic needs e.g. housing, food etc. and the provision of statistics to the government to determine the level of unemployment in the country".
Further importance could be: its assistance in the determination of the standard of living of the people in a country through per capital income; using the statistics of the number of people in a country to formulate economic policies e.g. revenue formula is at times based on population figures; the estimation of the number of immigrants in a country, the assistance to the government in the distribution of resources e.g. areas of high population will get more resources than areas of low population; giving the government an idea of the different population in various parts of the country and this can help in the provision of social amenities like housing, water, electricity, roads, schools, hospitals etc. It doesn't just end there, Population census is also very vital in giving detailed information to the government on areas of the country where population per land area is high or low; reveals level of man power by helping to reveal the total number of people who are working, when the level of manpower is high, the economic development of the country is assured and assists international agencies and governments in giving aids and other assistance to countries; assists international investors in making investment decisions. In some developing nations, Population is often used to allocate parliamentary seats. States or regions with high Population are given more parliamentary seats than states/regions with low population.
So all said and done, population census as we can now see is far beyond just counting the population of a particular area at a particular time. It can go a long way in helping an area's or nation's economy to grow even as it varies from one year to another. (www.senicoms.blogspot.com)
