Population data (its size, composition, location, employment patterns of human beings) has a great scientific and practical value. With the economic reforms undertaken in the country, growing needs in comprehensive and detailed information on the status and progress of demographics, the importance of the social dimension of the information are greatly needed. The main sources of data on the population census are: the current statistical accounting of natural and mechanical movement; selected socio-demographic and special surveys; lists (calculation) and population registers. These sources do not replace, but complement each other to form a unified system of information on the population.
The population census is an ultimate source of information. It provides the most complete and accurate information about the population. Current accounting of newborn; dead; recently arrived to a territory and retired from it - this data allows you to define the population annually, based on the latest census. To avoid double-counting, the pass and the census there are categories of people, depending on the nature of their residence in the territory present and resident population.
The permanent population (PP1) is a set of persons habitually reside on the territory, regardless of their location at the time of posting. The resident population, you can select a group of individuals at time of posting outside the built-up area or territory. A group of persons described as temporarily absent (SB).
Present population (PP2) refers is a collection of individuals in the territory at the time of registration, regardless of their place of residence. The resident population are temporary residents (RP) - persons at time of posting to the territory, but having a permanent residence abroad. Among the population, and there is a following relationship:
PP1=PP2+SB-RP;
PP2=PP1+RP-SB.
In the period between censuses the number and gender composition of the population are calculated on the basis of census data and current accounting of population movement, which is the current recording of vital events as they occur (births, deaths, marriages, divorces, arrivals, departures) on the basis of processing information, data, special sample surveys of population movements, are so-called population estimates-estimate of the number of residents in its territory or part thereof without the special census.
An important source of population data is a specific demographic survey. Its task is to get the most in-depth and detailed characteristics of population phenomena that cannot be obtained because of the complexity of collecting such information from the current accounting data or census. For example, for the purposes of population projections is a desire of the spouses to have children, on the sources and amounts of income of families with different numbers of children, methods of birth control, the desire of people to move to another region of the country. Since the population is constantly changing in many ways; inhabitants track statistics of population movement: a natural and mechanical. The natural movements of people mean population change through births and deaths.
There are also marriages and divorces, as they are in the same order with births and deaths. The absolute vital indicators include: number of births (n); number of deaths (M); natural increase (decrease) of the population-difference between the number of births and the number of deaths. Motion is a change in the size of the population through migration, movement of persons across the country, region, area (internal migration), or across the borders of the country (international migration).
To characterize the size of the mechanical movement of the population (migration) use the following absolute mechanical movement: the number of arrivals to the territory; dropout; the migration turnover (total number of arrivals and departures); the difference between the number of arrivals and departures-migratory balance.
Combination of research methods used in population statistics has a number of methods available to the general theory of statistics, mathematical methods and techniques developed in the population statistics. Find extensive use in the study of statistical methods: a study on the dynamic graphical study phenomena index, selective and balance.
While examining the phenomenon over time, you must describe the intensity and calculate averages of the dynamics. To characterize the intensity changes over time, such indicators will be: absolute growth, growth rate, and the absolute value of a one percent increase. When data is compared with the period of time (o) in a number of speakers have benchmarks. The same comparisons with the previous period or point in time, is said to be on chain indices.