Population data are the indicators of the various information of population like birth, death, migration, age, sex, marital status, religion, literacy, language, occupation, etc. Such data help to formulate and implement the various policies and planning in a country. Economic, social, cultural and political development takes place on the basis of the data. Population data can be found from various sources.
On the basis of the nature of data, they can be classified into two groups as follows:
1. Primary sources : First- hand data which are collected by thecensus, vital registration, sample survey, administrative records, population register, etc are primary sources of population data.
2. Secondary sources : The data which are found from individual person, organizations, agencies, books, journals, magazines, annual reports, etc. are secondary sources of population data.
Among the various sources of population data on the basis of method, following are most frequently used resources: -
Census is the main source of demographic data. UN (1970) defines census as “the total process of collecting, compiling, evaluating, analyzing and publishing demographic, economic and social data pertaining at a specified time to all persons in a country or in a well- delimited territory of a country”.
Census can be conducted on the basis of two methods:
The evidence of census was found to start in Bolivia in 4000 BC, China in 3000 BC , Egypt in 2500 BC, and in India during the period of Ashoka in 330 BC to 270 BC, which was for the purpose of tax collection. The modern census was started in 1665 AD in New France and Canada (Acadia). The USA started it in 1790 AD, Britain in 1801 AD and India in 1872 AD.
The first census carried out in Nepal in 1968 BS. After that every 10 years, the census was carried out. The census 2009/11 BS was said to be thescientific census of Nepal. Other censuses of Nepal were 2018 BS, 2028 BS, 2038 BS, 2048 BS, 2058 BS and the last one was 2068 BS. The last census 2068 BS was the 11th census of Nepal.
The censuses of all countries are almost similar because it contains all the lists recommended by UNO.
The following things are found to be included in the census list:
Vital Registration System (VRS) is also known as Civil Registration System. In a simple sense, recording of birth and death is vital registration. In this system, various vital events like birth, death, marriage, divorce and migration are recorded. UN experts have defined vital registration as “a legal registration, statistical recording, and reporting of the occurrence of vital events which includes live birth, death, fetal death, miscarriage, divorce, annulment, legal separation and marriage”.
It was first started in England in the16th century. It was started in Nepal in 1st Baisakh 2034 BS in 10 districts. The coverage of the system was increased in 17 districts in 2035 BS, 34 districts in 2037 BS, 40 districts in 2038 BS and all 75 districts in 2047 BS. After 2050 BS, the Registrar’s office was shifted under the Ministry of Local Development. All VDC’s and Municipalities run this system locally in Nepal.
Sample survey is also another important source of population data. Complete national enumeration is conducted in the survey. Data are collected in only some selected household and population in order to infer the characteristics of theentire population. It can be defined as the process of collecting, compiling, evaluating and publishing demographic, social and economic data about the sampled population in order to infer the general behavior of theentire population of a place or a country in a given time period. The sample survey was started in England in the19th century. If it is conducted in regular interval of time, census operation is not needed. For example, census is not conducted in Afghanistan.
The sample survey has the following operational processes:
These are the information on population collected by different administrative authorities. Useful and necessary data are kept as a record in different offices.
Some of the administrative records are as follows:-
The indices that are taken on the basis of various aspects of population such as birth, death, migration, gender, marital status, religion, casts etc. are known as population statistics. These are obtained from two main sources: primary sources and secondary sources.
The official counting of all people in a certain country carried out at set intervals is known as census. Census is the main source of population statistics. There are two main methods of census:
|A census||A sample survey|
|This is counting of whole population within a certain time frame||This is counting of a small portion of a population.|
|This is the most comprehensive and detailed form of population counting.||This is a small and limited form of population counting.|
|It is lengthy and costly.||Its quick and economical.|
|It is held with long time intervals.||It is held with short time interval.|