Reference metadata describe statistical concepts and methodologies used for the collection and generation of data. They provide information on data quality and, since they are strongly content-oriented, assist users in interpreting the data. Reference metadata, unlike structural metadata, can be decoupled from the data.
North Gate, Boulevard du Roi Albert II, 16 1000 Bruxelles
1.6. Contact email address
Confidential because of GDPR
1.7. Contact phone number
Confidential because of GDPR
1.8. Contact fax number
Confidential because of GDPR
2.1. Metadata last certified
19 June 2025
2.2. Metadata last posted
19 June 2025
2.3. Metadata last update
19 June 2025
3.1. Data description
Number of employees and self-employed persons
Nombre de salariés/nombre de personnes occupées
Aantal werknemers/aantal werkzame personen
Arbeitnehmer/Beschäftigte
Hours worked by employees
Heures travaillées
Gewerkte uren
geleisteten Arbeitsstunden
Gross wages and salaries
Masse salariale
Loonmassa
Gesamtlohnsumme
These indexes are designed to be indicators of the economic cycle.
The source of data are the administrative data from the NSSO (National Social Security Office).
For the number of persons employed, the administrative data from the NISSE (National Institute for the social security of the self-employed) are also used.
3.2. Classification system
NACE Rev. 2. classification (Statistical Classification of Economic Activities) is used.
3.3. Coverage - sector
INDUSTRY :
sections B to E of Nace Rev.2 (except : E37, E38 and E39)
MIGS
B_TO_E36
divisions of Nace Rev.2 : B to E36
CONSTRUCTION :
section F of Nace Rev.2
RETAIL TRADE :
sections G, G45, G46, G47 of Nace Rev.2
division G47, except Group 47.3 (G47XG473)
OTHER SERVICES :
aggregate of Nace sections H+I+J+L+M (except: M701, M72 and M75) + N
sections of Nace Rev.2: H, I, J, L, M (except: M701, M72 and M75) and N
divisions of Nace Rev.2: H, I and J
All size classes are included (no breakdown on size classes) and there are no cut-off.
3.4. Statistical concepts and definitions
Number of employees and self-employed persons, hours worked by employeesand gross wages and salaries are based on the NSSO data.
The largest category of individuals reported to the NSSO as employees are those working according to the terms of a work contract. This is a contract that binds an individual to carry out services under the authority of another individual.
For certain jobs or capacities, regulations have removed the doubts. It has been legally defined that certain persons always act in the capacity of an employee, even though for some of them there may not be a work contract (pharmacists, fellowship holders, transporters of goods,...).
Certain individuals are employees, but their employer need not report them to the NSSO due to the limited nature of their services.
The Belgian social security system does not apply only to Belgians working in Belgium. It may also apply to foreigners working in Belgium, Belgians working abroad and sometimes to foreigners working abroad.
Measured number of employees is the number of employees subject to NSSO (full time and per time) and the number of self-employed persons no subject to NSSO working during the reference period.
The total number of hours worked represents the aggregate number of hours actually worked for the output of the observation unit during the reference period. However, for administrative simplification reasons, hours worked are approximated by paid hours.
The objective of the wages and salaries index is to approximate the development of the wage and salaries bill. Wages and salaries include all sums in cash and benefits in kind paid to persons counted among the employees.
3.5. Statistical unit
reporting unit : legal unit or self-employed person
observation unit : legal unit or self-employed person
3.6. Statistical population
Enterprises subject to NSSO and self-employees to NISSE.
In the fourth quarter of 2024 (version Q+7), there were 4224042 legal units in the NSSO.
3.7. Reference area
All of the regions of Belgium are covered.
The Belgian social security system does not apply only to Belgians working in Belgium. It may also apply to foreigners working in Belgium, Belgians working abroad and sometimes to foreigners working abroad.
3.8. Coverage - Time
The administrative data of NSSO and NISSE are use for the first time in 2008.
Series were recalculated based on these administrative data from 2000.
3.9. Base period
Base year : 2021
index based on number of persons
index based on hours
index based on euros
The calendar quarter is the reference period
6.1. Institutional Mandate - legal acts and other agreements
The legal basis for this indicator is the European Business Statistics (EBS) Regulation:
Regulation (EU) 2019/2152 of the European Parliament and of the Council on European business statistics, repealing 10 legal acts in the field of business statistics (EBS-Regulation)
Commission Implementing Regulation 2020/1197 laying down technical specifications and arrangements pursuant to Regulation (EU) 2019/2152 of the European Parliament and of the Council on European business statistics repealing 10 legal acts in the field of business statistic (General Implementing Act)
Belgium applies for this indicator the transitional arrangements set in the Annex VII (3.a) of the General Implementing Act EBS, which means that the requirements of the STS R - Council Regulation No 1165/98 and its amendments (The EU Council Regulation 1165/98 concerning short-term statistics, amended by the Regulation 1158/2005, and Regulation 1893/2006 establishing the statistical classification of economic activities Nace Rev.2) will continue to apply until the reference period Q4 2023.
6.2. Institutional Mandate - data sharing
Data are sent to Eurostat.
7.1. Confidentiality - policy
There is a national law concerning the confidentiality of data (statistical law of July 4, 1962): data from reporting units which are individual or which can result in individual data may not be disseminated without permission of the reporting unit. In practice this means indices are not disseminated for sectors where:
there are only one or two reporting units;
there are three reporting units but one of them represents 70% or more;
Confidential indices are sent to Eurostat flagged as confidential data.
For the indices of number of employees and self-employed persons, number of hours worked by employees, gross wages and salaries for breakdown defined in point 3.3, there is no problem of confidentiality.
7.2. Confidentiality - data treatment
Confidential data are treated by suppression.
8.1. Release calendar
Release dates are fixed in advance for a calendar year.
8.2. Release calendar access
Access is given to all users, there are no limits.
8.3. Release policy - user access
Simultaneous release to all interested parties : Data are transmitted to Eurostat when they are published in Belgium
Identification of internal government access to data before release: The news are sent to the president of our ministery for information and to our general director 1 hour before publication
Transmission to Eurostat and further use of the statistics : Data are transmitted to Eurostat when they are published in Belgium. The transmission is done by use of edamis using BCS. The level of detail corresponds to the 2-digit level of NACE Rev. 2, the totals and the MIG's
The data are transmitted quarterly to Eurostat and disseminated quarterly to national users.
10.1. Dissemination format - News release
There are news on these indicators available on Dutch, French, English and German versions.
In these news, the bruto indices for the highest aggregates for industry, construction, retail trade and repar, services for the reference quarter are compared with the same quarter of year before, for the employees and persons employed. For the indices of hours worked and the gross wages and salaries, seasonally adjusted indices are compared.
10.2. Dissemination format - Publications
Name of national paper publications: press release. Name of national electronic dissemination: downloadable Excel files with the quartery indices
10.3. Dissemination format - online database
The news are a web document and is accompagnied by an excel table containing :
gross indexes
working day adjusted indexes (except for number of employees and self-employed persons)
trends (except for number of employees and self-employed persons)
seasonnaly adjusted indexes (except for number of employees and self-employed persons)
for Belgium for Nace 2 digits, Nace 3 digits , MIG's, sections B, C, D, E and totals
10.4. Dissemination format - microdata access
Microdata are not disseminated.
10.5. Dissemination format - other
Indices are transmitted to Eurostat to be used in calculating European aggregates and to be released as national data.
10.6. Documentation on methodology
There is no available methodology document.
10.7. Quality management - documentation
There is no available methodology document.
11.1. Quality assurance
For each step of the production chains, the data are controlled. The stability of different revisions are tracked. If the rate of revision is important then we try to give an explanation.
Once the figures produced, they are validated by our internal validation service before publication.
11.2. Quality management - assessment
checks carried out along the production chain of the indices and these are finally validated by our validation service before diffusion
12.1. Relevance - User Needs
Belgian national bank, Eurostat, Federations, Professional associations, Universities, Regional public services, Other users.
12.2. Relevance - User Satisfaction
no measure of user satisfaction but we receive feedback of users by mail, phone...
12.3. Completeness
all of the required series are available.
13.1. Accuracy - overall
These indexes are based on administrative data.
There are 3 versions of the same data for a reference quarter available at Q+2M, Q+4M and Q+7M.
Version Q+4M represents 95% of version Q+7M.
Only for the index of the number of employees and self-employed persons the reference quarter is first calculated based on Q+2M data then recalculated on the Q+7M data.
For the indices of hours worked by employees, gross wages and salaries the reference quarter is calculated based on more complete data Q+4M then recalculated on the Q+7M data.
All indices are sent to Eurostat and published on our website.
13.2. Sampling error
not relevant
13.3. Non-sampling error
Errors can come from the fact that the data Q+2M and Q+4M are less complete then data Q+7M.
The rates of revision between the calculations based on 2 versions of the data are generally rather low.
An other source of error can also come from errors in the attribution of the nace activities.
Errors are also detected in the old data before 2010.
14.1. Timeliness
The indexes are based on administrative data.
There are 3 versions of the same data for a reference quarter available at Q+2M, Q+4M and Q+7M.
The first index to calculate is the index of the number of employees and self-employed persons that must be released within 2 months for the fourth sectors: Industry, Construction, Retail trade and Services.
Generally, version Q+4M is available on time to provide official indexes for hours worked by employees, gross wages and salaries for all the asked sectors.
From this version Q+2M, official indexes for number of employees and self-employed persons are recalculated.
14.2. Punctuality
Data availability two months after the reference period and the computation time allow us to meet deadlines for the number of employees and self-employed persons.
15.1. Comparability - geographical
Not applicable.
15.2. Comparability - over time
Not applicable.
15.3. Coherence - cross domain
No regular confrontation is made, but comparisons are made on an ad-hoc basis, especially when results seem contrary to expectations.
15.4. Coherence - internal
Not applicable.
Burden on respondents
For these indices, we use administrative data.
Cost associated with the production of these indexes
1person for ~200 hours/year
17.1. Data revision - policy
The same revision policy is applied to the data released nationally and transmitted to Eurostat. The general belgian revision policy is available on our internet site.
For number of employees and self-employed persons: the indices for the five last quarters are recalculated based on Q+2M versions of the data for the reference quarter and based on Q+7M versions of the four last quarters.
For hours worked by employees, gross wages and salaries: the indices for the five last quarters are recalculated based on Q+4M versions of the data for the reference quarter and based on Q+7M versions of the four last quarters.
Indices of the five last quarters are considered as provisional. Other are definitive.
These indices are published on our website.
Moreover, if there are errors then series are recalculated.
17.2. Data revision - practice
For number of employees and self-employed persons: the indices for the five last quarters are recalculated based on Q+2M versions of the data for the reference quarter and based on Q+7M versions of the four last quarters.
For hours worked by employees, gross wages and salaries: the indices for the five last quarters are recalculated based on Q+4M versions of the data for the reference quarter and based on Q+7M versions of the four last quarters.
Indices of the five last quarters are considered as provisional. Other are definitive.
These indices are published on our website.
Moreover, if there are errors then series are recalculated.
All series since 2000 will be re-referenced in the new reference year 2021.
18.1. Source data
Type of source : administrative sources
Frame on which the source is based : not relevant
Sample or census : assumed to be a census
Criteria for stratification : not relevant
Threshold values and percentages : not available
Frequency of updating the sample : not relevant
18.2. Frequency of data collection
Quarterly
18.3. Data collection
Questionnaires used in the survey : not applicable
Planned changes in national questionnaires : not applicable
Data collection media : not requested
Planned changes in data collection methodology : not required
18.4. Data validation
Checks are carried out throughout the production chain indices. These are also validated by another service before distribution.
Administrative data are quarterly transferred from the NSSO in our datawarehouse. The presence of the different versions of the data and the presence of the data for the last quarter are checked.
The gross indexes are calculated for the different quarters sinds 2000.
For the previously calculated indices, the revision rates are analyzed. If these rates exceed 10%, we search the explanation in the data.
We compare indices of the last trimester to the indices of the previous trimester.
Final tables and press releases are validated by our validation service : format, content, missing informations, layout of press release,...are verified.
If results appear abnormal, the validation service recontacts the responsible for verification.
18.5. Data compilation
Estimates for non-response : non-response is estimated by comparing the quarter with the quarter before (taking into account bankruptcy)
Estimates for grossing-up to population levels : not required
Type of index : simple index (proportion to average of base year)
Method of weighting and chaining : not required
Planned changes in production methods : not required
18.6. Adjustment
Number of employees and self-employed persons: all the series provided are unadjusted
Hours worked by employees: unadjusted and calendar adjusted series using Tramo Seats of JDemetra+
Gross wages and salaries : unadjusted and calendar adjusted series using Tramo Seats of JDemetra+
The following series are published in Belgium :
Industry : 08 - 33, 35, 36, B, C, D, E, B_TO_E36, MIG_CAG, MIG_COG, MIG_DCOG, MIG_ING, MIG_NDCG, MIG_NRG
These indexes are designed to be indicators of the economic cycle.
The source of data are the administrative data from the NSSO (National Social Security Office).
For the number of persons employed, the administrative data from the NISSE (National Institute for the social security of the self-employed) are also used.
19 June 2025
Number of employees and self-employed persons, hours worked by employeesand gross wages and salaries are based on the NSSO data.
The largest category of individuals reported to the NSSO as employees are those working according to the terms of a work contract. This is a contract that binds an individual to carry out services under the authority of another individual.
For certain jobs or capacities, regulations have removed the doubts. It has been legally defined that certain persons always act in the capacity of an employee, even though for some of them there may not be a work contract (pharmacists, fellowship holders, transporters of goods,...).
Certain individuals are employees, but their employer need not report them to the NSSO due to the limited nature of their services.
The Belgian social security system does not apply only to Belgians working in Belgium. It may also apply to foreigners working in Belgium, Belgians working abroad and sometimes to foreigners working abroad.
Measured number of employees is the number of employees subject to NSSO (full time and per time) and the number of self-employed persons no subject to NSSO working during the reference period.
The total number of hours worked represents the aggregate number of hours actually worked for the output of the observation unit during the reference period. However, for administrative simplification reasons, hours worked are approximated by paid hours.
The objective of the wages and salaries index is to approximate the development of the wage and salaries bill. Wages and salaries include all sums in cash and benefits in kind paid to persons counted among the employees.
reporting unit : legal unit or self-employed person
observation unit : legal unit or self-employed person
Enterprises subject to NSSO and self-employees to NISSE.
In the fourth quarter of 2024 (version Q+7), there were 4224042 legal units in the NSSO.
All of the regions of Belgium are covered.
The Belgian social security system does not apply only to Belgians working in Belgium. It may also apply to foreigners working in Belgium, Belgians working abroad and sometimes to foreigners working abroad.
The calendar quarter is the reference period
These indexes are based on administrative data.
There are 3 versions of the same data for a reference quarter available at Q+2M, Q+4M and Q+7M.
Version Q+4M represents 95% of version Q+7M.
Only for the index of the number of employees and self-employed persons the reference quarter is first calculated based on Q+2M data then recalculated on the Q+7M data.
For the indices of hours worked by employees, gross wages and salaries the reference quarter is calculated based on more complete data Q+4M then recalculated on the Q+7M data.
All indices are sent to Eurostat and published on our website.
index based on number of persons
index based on hours
index based on euros
Estimates for non-response : non-response is estimated by comparing the quarter with the quarter before (taking into account bankruptcy)
Estimates for grossing-up to population levels : not required
Type of index : simple index (proportion to average of base year)
Method of weighting and chaining : not required
Planned changes in production methods : not required
Type of source : administrative sources
Frame on which the source is based : not relevant
Sample or census : assumed to be a census
Criteria for stratification : not relevant
Threshold values and percentages : not available
Frequency of updating the sample : not relevant
The data are transmitted quarterly to Eurostat and disseminated quarterly to national users.
The indexes are based on administrative data.
There are 3 versions of the same data for a reference quarter available at Q+2M, Q+4M and Q+7M.
The first index to calculate is the index of the number of employees and self-employed persons that must be released within 2 months for the fourth sectors: Industry, Construction, Retail trade and Services.
Generally, version Q+4M is available on time to provide official indexes for hours worked by employees, gross wages and salaries for all the asked sectors.
From this version Q+2M, official indexes for number of employees and self-employed persons are recalculated.
