Stock tables

Stock tables

Template for presentation of stock estimates





Main data source

Short explanation


Total stocks


Gender composition


Age composition


Nationality composition


Economic sector composition


Other subgroups



Stock estimates refer to the total number of irregular foreign residents (IFR) or irregular foreign workers (IFW) in a country at a specific point of time. Each table consists of estimates of absolute numbers and of indicators for the composition with regard to gender, age, nationality, and sector of economic activity. All relative indicators are percentages of the groups in the total IFR or IFW population and thus should add up to 100%.

  • Total stocks: total stocks of irregular foreign residents or workers (for the whole country or specific cities or regions). 
  • Gender composition: absolute estimates, or estimated percentage of men and women.
  • Age composition: absolute estimates, or estimated percentage of age groups: 0-14 years (children); 15-60 (youth and persons in main working age);  60 and older (persons in or close to retirement age).
  • Nationality composition: absolute estimates individual nationalities, or estimated percentage of nationalities, sorted in order of quantitative relevance.
  • Economic sector composition: absolute estimates for individual sectors, or estimated percentage of sectors, sorted in order of quantitative relevance. Indicators differ strongly with regard to sector definition and specification. 'Private household employment' was summarized as one sector.
  • Other subgroups: open category for any estimate about groups of specific concern. It was suggested that these estimates could concern former asylum seekers, refugees or prostitutes, but any subgroup of irregular migrants for which an estimate exists could be added under this heading.


Definitions of irregular migrants are problematic and complex.  The database distinguishes between two broad types of irregularity, a simplification necessary in order to achieve some degree of comparability. Additions, like incl. EU (includes EU-citizens), 15 years plus (excludes children up to 14 years of age), IFR/working (excludes unemployed, children and aged persons without residence status), indicate important limitations of definitions.


The database summarizes estimates from 2000 to the present. Stock estimates are in principle estimates made at a specific point in time, usually the 31st of December of the year for demographic data. However, irregular migration estimates often do not indicate specific dates, only a year, if at all.
Note that the definition of EU-countries has changed in this time due to the accession of new member states. As EU citizens are rarely irregularly resident, this has a high impact on IFR numbers.


EU-member states


15 countries (Austria, Belgium, Denmark, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, Netherlands, Portugal, Spain, Sweden, United Kingdom)


25 countries (15 countries + Cyprus, Czech Republic, Estonia, Hungary, Latvia, Lithuania, Malta, Poland, Slovakia, Slovenia)


27 countries (25 countries + Bulgaria, Rumania)


Estimates of irregular migrant populations may consist of one or more values which are sorted in the following way.


Estimate indicates that there are at least this many irregular migrants (also refered to as a conservative estimate). The lower value of a range estimate is also entered under minimum.


Estimate for which no indication of minimum or maximum estimate is feasible. The middle values of range estimates are also entered under central.


Estimate indicates that there are, at most, this many irregular migrants. Upper value of a range estimate is also entered under maximum.


The main type of data is indicated in the following way.

Data source

Short explanation

Enforcement data

Enforcement authorities reveal irregular migrants? status in the course of their work, usually against the migrants' will (e.g. data from border guards, police, labour market inspection units).

Regularisation data

Irregular migrants may self-identify to authorities to become regular. Includes records of permanent regularization procedures and programmes.

Support service data

Irregular migrants may be identifiable in  some services (e.g. health services for uninsured persons). Support service data are based on records about such services.

Administrative data

All organisational statistics that cannot be summarized under the specific headings above (e.g. demographic data, school registers).

Census/ general survey

All surveys that are directed at general populations are included in this category. Census or population surveys often include a part of the irregular migrant population, although they are not always identifiable.

Expert survey

Expert surveys include the systematic collection and evaluation of estimates and indicators from institutional experts and/ or key informants in immigrant communities.

Migrant survey

All surveys in which irregular immigrants are directly targeted.

Employer survey

All surveys targeting employers and requesting information on the irregular employment of foreign nationals.

Economic data

Data on production, income, demand, etc.,  that is used for indirect estimations.

Multiple sources

Studies relying heavily on several of the above data sources.


Usually quotations of estimates, or expert opinions without explanation

For more information about estimation methods, see the methodological report.  


Indicates the type of person or institution supplying the estimate and explains briefly the estimation procedure.   


References are listed at the end of the table. They include references to CLANDESTINO country reports and the Classification Report, indicated as Working paper No.1 of the Database on Irregular Migration.