Why and how is a census carried out

Frequently asked Questions

What is a register count?

In a register census, the characteristics of the survey units are not collected from the persons themselves using questionnaires, but mainly taken from administrative registers.

How did the register count come about?

The 2001 census was the last conventional census in Austria to be collected using questionnaires. In June 2000 the Council of Ministers decided to carry out the 2011 census as a register census. For this reason, the first preparatory work was carried out as early as the 2001 census to set up suitable administrative registers.

What are the legal bases for register counting?

  • Regulation No. 763/2008 of the European Union of July 9th, 2008, regarding population and housing censuses
  • Register Census Act, Federal Law Gazette I No. 33/2006
  • Financial Equalization Act 2008
  • Federal Statistics Act 2000
  • Data Protection Act 2000
  • E-Government Area Delimitation Ordinance 2004

When does the register or sample count take place?

The test count took place on October 31, 2006, the real count on October 31, 2011.

Have results been provided after the sample count?

In April 2008, the Austrian Federal Statistical Office prepared a report for the federal government, including the results and their evaluation. The results of the trial census were published on the homepage of the Austrian Federal Statistical Office (including in "A look at the community")

Which data are still available with a register-based census at the municipality level, which are no longer available?

The scope of the data to be collected from the individual administrative areas will not exceed that of the population, building and housing censuses as well as the 2001 census of workplaces. However, in comparison to the 2001 census, surveys of occupation, colloquial language, certain characteristics of commuter behavior (time required, type of means of transport and frequency of commuting) will no longer be possible because such data are not contained in the registers and administrative files. In the 2006 trial census, no data were collected on religious beliefs or colloquial language. All data will be available at the community level.

What happens to data gaps?

Existing gaps in the available register and administrative data are closed by means of well-founded estimates. These are carried out with the help of suitable statistical methods. However, this was partly the case with the previous large-scale censuses, which also had gaps and inconsistencies that had to be corrected.

How will missing features be recorded in the future?

Occupation: Is continuously recorded in the microcensus as an ISCO 4-digit code and is therefore available as a large sample result that is representative of the federal states. The amendment of the Register Census Act allows estimation procedures with regard to the characteristic “occupation”.

Colloquial language / religious denomination: The competent ministry can order a full survey of the colloquial language in personal form and a full survey of the religious denomination in non-personal form by ordinance if this is absolutely necessary for the fulfillment of federal tasks. These full surveys can only be carried out in parts of Germany. In any case, these questions were not allowed in the 2006 sample census.

How does the data protection of the register counting work?

In accordance with Section 6 (2) of the RZG, personal data must be transmitted to Statistics Austria using the encrypted bPK AS and the encrypted bPK of the area of ​​activity concerned. In this way, Statistics Austria receives a completely anonymous database. It can then link this with other data from another register-keeping facility, anonymized in the same way and provided with the same bPK AS.

In this way, better data protection is guaranteed than with a traditional census, in which census organs that belonged to the same community and often had a close relationship through neighborhood or acquaintance with the population counted had to carry out the census and check the results.

What is a bPK? / How did it come about?

The bPK (= area-specific personal symbol) comes from the E-Government Act and is used to handle personal data records completely anonymously without using the name in data applications.

In cooperation with the bodies responsible for data protection and e-government in the Federal Chancellery, a collection and consolidation process was developed that eliminates the direct personal reference of the data to be supplied to Statistics Austria and still allows a link.

This procedure is made possible by the e-government law, in that each register-keeping institution relevant for register counting has its data stock to be supplied to Statistics Austria with an "area-specific personal identifier for official statistics" (bPK AS: This 172-digit bPK is generated for each person on the basis of their identity data (name, date of birth, ...) provided by the master number register authority from the master number and this in turn derived from the ZMR number, encrypted using a random process and transmitted to the register-keeping offices.), which can only be decrypted by Statistics Austria and does not allow any conclusions to be drawn about identifiable persons.

Will the 2011 register census only take place in Austria?

Register counts take place in a wide variety of countries. I.a. in Denmark, Finland, Norway, Sweden and Slovenia.

What makes the Austrian method so special?

The principle of redundancy is the decisive characteristic of the Austrian register census: Survey objects and their characteristics are not only obtained from a single data source if possible, but from all available administrative registers and other administrative data sources as well as from statistical registers. For the purpose of collecting and checking the consistency of the characteristics, data sources from 15 different register areas are linked and compared with one another.

Furthermore, the use of register data enables a more detailed evaluation of the characteristics contained therein: For a long time in Austria administrative structures (federal states, political districts, municipalities) and their further hierarchical subdivisions, the statistical census clusters, had to get along. But only by switching to a coordinate-based storage of the individual data is it possible to offer statistical data on the basis of regional statistical grids with different cell sizes. Regional statistical grids are comprehensive, regular, hierarchical, can be subdivided or combined. As a result, they can be used equally well for small-scale, regional, supra-regional and national investigations. They are independent of administrative boundaries and thus of possible border changes and therefore allow purely subject-related territorial delimitation.

What types of censorship are there worldwide?

  • Traditional census: direct survey of the entire population using questionnaires or interviews.
    Where: e.g. Greece, Great Britain, Ireland, Croatia, Luxembourg, Portugal, Hungary
  • Register census: Obtaining the required information from existing administrative registers.
    Where: e.g. Denmark, Finland, Norway, Sweden, Austria, Slovenia
  • Mixed forms: for example traditional censuses, which are combined with the use of a register or register censuses, which are supplemented with a sample, etc.
    Where: e.g. Germany, Netherlands, Switzerland, Spain
  • Rolling census: annual data collection through direct questioning of part of the population; the scope of the surveys mostly depends on the size of the community.
    Where: France

Which country was the first to do a register census?

Denmark. Denmark is not only one of the few countries that does a full register census, it was also the first country in 1981 to switch completely from the traditional census to the register census.

What are the subjects of the register census?

The register census knows three original survey items, with further items derived from them:


  • people

Workplace census

  • Companies
  • Workplaces

Counting of buildings and apartments

Which characteristics are recorded by the register census?

The catalog of characteristics is based on that of the 2001 census, whereby at the individual level some characteristics that were collected in 2001 can no longer be shown or can be shown in a regionally very limited manner.

The characteristics surveyed will include:


    • gender
    • Age
    • nationality
    • marital status
    • Country of birth
    • Year of arrival in Austria
    • usual place of residence a year earlier


    • Educational level (national and international)
    • Field of training (national and international
    • Most important ongoing training

Households, families:

    • Type of household
    • Position in household
    • Size of household
    • Nuclear family type
    • Position in the family
    • Size of the nuclear family
    • Number of Children


    • Commuter type (employed or schoolgirls, schoolchildren, students)
    • Distance category

Acquisition characteristics:

    • Employment status
    • Position in the job
    • job
    • Marginal employment
    • Full / part time employment


    • Companies
    • Workplaces
    • ÖNACE
    • Legal form of the company or assignment to the company
    • Number of self-employed
    • Number of employees

Buildings and apartments:

    • Building type
    • Total usable area
    • Construction period
    • Building owner type
    • Usable areas according to type of use
    • Furnishing
    • Number of residents
    • Type of use
    • Type of accommodation
    • Accommodation type
    • Number of rooms

Which characteristics cannot be recorded by the register count?

The characteristics that can no longer be collected or that can be collected to a limited extent include

  • Occupation (only shown at state level)
  • Colloquial language: is not included in any administrative register, but could be collected on a personal basis based on an ordinance of the responsible Federal Minister in accordance with Section 1 (3) RZG
  • Religious affiliation: could not be ascertained personally due to a regulation of the responsible federal minister according to § 1 Abs. 3 RZG.
  • Travel time and means of transport for the commuting target statistics are not included in any register and therefore cannot be displayed.

Who are the data sources of the register census?

In Austria, register counting is based on 15 register areas, with a distinction being made between base registers and comparison registers. Comparison registers are used to ensure the quality of the basic data, by means of which the correctness and completeness of the survey characteristics can be checked.

Base register:

  • Central Resident Register (ZMR)
  • Data from the Main Association of Social Insurance Institutions (HV)
  • Tax data
  • Labor Market Service (AMS) data
  • Educational level register
  • School and university statistics
  • Building and Housing Register (GWR)
  • Business and Agriculture and Forestry Register

Comparison register:

  • Foreign register
  • Federal and state employer data
  • Social assistance data of the countries
  • Family allowance register
  • Civil Service File
  • Military service file
  • Central registration record

All of the census data supplied by the various registers and administrative data owners were linked to one another via the “area-specific personal identifier, official statistics”.

What is the difference between a register census and a population census?

No difference. The term register counting only refers to the special way in which the data is collected. To be correct, one would have to distinguish between “register census” and “conventional census”.

Why is there no longer any questioning of citizens? / Why is there no more census?

The census continues. It just changes the way the data is collected; no longer via questionnaires but directly via the available data from the administrative registers. This new method is cheaper than the old one, in a ratio of 1: 7.

Why do we even need a register count?

Censuses are necessary to get an accurate overview of the population, the number of buildings, apartments and workplaces every ten years. This data is required by politics, administration, science, the media and the general public in order to be able to plan, implement and assess projects. It is particularly important to determine the size of the population for the financial equalization between the federal, state and local governments and the number of citizens (= Austrian citizens) for elections.

Advantages and disadvantages of register counting:


Register censuses are carried out instead of conventional censuses because

  • Register counts are much cheaper (€ 9.9 million instead of € 72 million)
  • there is no burden on the respondent,
  • Much of the requested data is available in the various registers anyway,
  • Counts every 10 years are too rare and a shortening of the interval with the traditional survey form would be much too expensive; Register counts, on the other hand, can be ordered every 5 years.


  • Dependence on various authorities in order to maintain or achieve the quality and timeliness of registers
  • Legal delivery deadline for data providers, eight months after the reference date (June 30, 2012)
  • The publication of detailed evaluations is difficult or even impossible in some cases, as only limited information is available.

What is the target formulation of the register count?

Through optimal use of existing registers and administrative data,

  • by clarifying the definition of the objects and characteristics, if possible also harmonization,
  • by improving the quality of the registers where necessary and
  • by linking the registers via unique identifiers

a register census should provide the best possible representation of reality at a reasonable cost despite the lack of primary statistical surveys.

What are the principles of register counting?

  • Limited wreath of features: not everything that is contained in the registers is used, only that which has been collected in previous censuses
  • Reduced wreath of features: for some of the features recorded so far there is no or only incomplete register data, which is why they have to be dispensed with (means of transport and time spent commuting, etc .; religious belief and colloquial language)
  • Register adaptation: Improvement of the quality and addition of certain characteristics to the register
  • Redundancy: the same masses and features from different registers in order to achieve optimal quality

For when, what results are planned?

November 2011 - Presentation of the first results of the register census: provisional population figure on October 31, 2011 with demographic characteristics and from the "mini" register census 2009: employment statistics, commuting target statistics, education data

06/30/2012 - End of the deadline for data delivery

November 2012 - Results of the "Mini" register census 2010

June 2013 - Publication of the population of the register census 2011

Second half of 2013 - Publication of the detailed results of the 2011 register census

What empirical values ​​are there for register counting?

Nationally there are the results of the sample census 2006, in which a complete register census was carried out for the first time, together with a survey of 10,000 households. The results of the sample count were overall satisfactory, and the detailed results were even excellent. The determined population was used as the basis for determining the financial equalization.

Are there any differences to previous workplace censuses?

Yes, in 2011 the workplaces (and companies) in the agricultural and forestry sector are also counted for the first time.

© STATISTICS AUSTRIA, last change on 02/27/2019