Population Grid 2021

National Statistical Institute

Regional Statistics and Geographical Information 

Arslan Ahmedov

Head of Department

2 P.Volov Str, 1038 Sofia, Bulgaria

• Responsible party: [email protected]
• Metadata point of contact: [email protected]

This spatial dataset contains population data on the selected topics from Census 2021 survey (final results), presented at the level of 1000 x 1000m grid cells. 

The dataset covers the territory of Bulgaria. Population distribution is based on the place of usual residence at the census reference date (07/09/2021). Values for the total population and for the population categories in grid cells are aggregated from point locations of individual census records.

Total population in the dataset (allocated on map):

Resource type: Geodatabase (GDB)

Not applicable.

Not applicable.

‘Total population’ means all persons of a grid cell whose usual residence is located in that grid cell

‘Usual residence’ is the place where a person normally spends the daily period of rest, regardless of temporary absences for purposes of recreation, holidays, visits to friends and relatives, business, medical treatment or religious pilgrimage.

The following persons alone shall be considered to be usual residents of the geographical area in question:

(a) those who have lived in their place of usual residence for a continuous period of at least 12 months before the reference date;

(b) those who arrived in their place of usual residence during the 12 months before the reference date with the intention of staying there for at least one year.

Where the circumstances described in point (a) or (b) cannot be established, ‘usual residence’ shall mean the place of legal or registered residence.

‘Sex’ refers to the biological and physiological characteristics that define men and women.

‘Age’ is the age reached in completed years of age at the reference date.

Persons.

Persons enumerated in the 2021 census are those who were usually resident in the territory of the reporting country at the census reference date.

The reference area covers Bulgaria's territory.

2021-09-07 T00:00:00

Not applicable.

Number of persons.

2021-09-07 T00:00:00

EU implementing regulation 2018/1799 on dissemination of selected topics of the 2021 population and housing census geocoded to a 1 km2 grid;
Population and Housing Census 2021 in the Republic of Bulgaria Act

Data sharing is arranged according to the 2021 Population Census and Housing Census in the Republic of Bulgaria Act and Rules for dissemination of statistical products and services of the National Statistical Institute.

The census data privacy policy is implemented on the basis of the 2021 Population Census and Housing Census in the Republic of Bulgaria Act, according to which NSI undertakes to ensure the protection of individual data by applying the relevant organizational and technical means.

This includes applying methods to statistically control the disclosure of individual or sensitive data on aggregate statistics that may be linked to identify a particular statistical unit.

The data in the 1000m population grid is not sensitive/confidential. No observation values are suppressed.

The schedule of census release dates.

https://www.nsi.bg/bg/node/19795

Data from the population and housing censuses are disseminated every decade.

News releases by Census topics are available on NSI webpage and on Census 2021 webpage.

No publications available.

1.EU CENSUS HUB (Eurostat)
2.Information System Infostat (NSI Bulgaria)

Not applicable.

Other dissemination formats are listed in Rules for dissemination of statistical products and services of the National Statistical Institute.

In Bulgarian language only - Census 2021 webpage

Methodological documents, questionnaires, instructions and reports available on the Census 2021 webpage.

This dataset represents final population data results of the 2021 Census collection in a 1 km square grid for the territory of Bulgaria. Spatial-based criteria are used when calculating aggregates. 

Population data is collected during the census period (7. September 2021 – 10. October 2021) via online self-enumeration and door-to-door interviews. The proper application of criteria for place of usual residence is assured by trained enumerators and detailed instructions in online questionnaires.

Location data in terms of geographic coordinates (longitude and latitude) of dwelling units were collected by NSI. Dedicated census fieldwork and in-office activities were carried out (using mobile devices and desktop applications) to provide a precise point reference base for the whole territory. Census data were georeferenced to the point locations at the time of collection by the enumerators or during the self-enumeration campaign via tools provided by the e-census platform.

High quality of the geographical data is ensured via the use of the latest available national cadastral maps, cadastral data and orthophoto imagery. Geocoding, census mapping and census list production activities are implemented with the collaboration of the local authorities and crossed several validation steps in the preparatory and production stages.

An integrated quality and security management system has been implemented in respect of all Census stages and in accordance with the requirements of BDS EN ISO 9001: 2015 and BDS EN ISO 27001: 2017. The certificate fully meets all international requirements and guarantees the quality of the processes and information security of the entire statistical and information infrastructure of the NSI, both at national and regional levels.

The census data are addressed to policymakers, researchers, media and the general public.

No user satisfaction surveys are carried out.

Data are available on all breakdowns of census topics specified in Annex I of the Regulation (EU) 2018/1799 for the 1000m grid. 

Reliability and accuracy of grid data for the topic ‘place of usual residence’

• 37% of the census population is enumerated via online questionnaire. Location of the place of usual residence collected via self-enumeration is subject to additional verification procedures carried out by the enumerators during the fieldwork; Locations pinpointed in self-enumeration checked for consistency with provided by respondents detailed address descriptions;
• 54% of the census population is enumerated via paper questionnaire. Proper application of criteria for place of usual residence assured at data collection with trained enumerators;
• 9% of the census population is imputed from administrative sources. For these records, the place of residence corresponds to the current address of the persons on the census reference date of 7 September 2021, according to national law. The 12-month criterion was not applied.

Not applicable.

Not applicable.

The Census 2011 population grid data was produced using a combination of aggregation and disaggregation techniques, while the Census 2021 grid data is entirely aggregated from point locations. The two datasets, from 2011 and from 2021, are not fully comparable.

Not applicable.

No differences.

Census 2021 budget.

National policy allows the revision of already published data if there are serious reasons for doing so.

Census 2021 dataset, geocoded to high-preceision geographic coordinates of place of usual residence.

Decennial.

Geospatial data derived during census survey opperations.

Consistency checks on aggregated values by categories.

Spatial based criteria used when calculating aggregates. Values for the total population and for the population categories in grid cells aggregated from point locations of individual census records. 

Not applicable.

None.