International Migration Database
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The Organisation for Economic Co-operation and Development (OECD) International Migration Statistics include data on foreign and immigrant populations, foreign workers, migration flows and naturalisations for OECD member countries and others for a variety of periods from 1980 onwards.

This summary table contains data for 1980 onwards on the following variables: inflows and outflows of foreigners, asylum seekers, stocks of foreigners and foreign born, and naturalisations. Countries covered are: Australia, Austria, Belgium, Canada, Denmark, Finland, France, Germany, Greece, Ireland, Italy, Japan, Luxembourg, the Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, the United Kingdom, and the United States.

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Bibliographic citation:
Organisation for Economic Co-operation and Development: International Migration Statistics (June 2018 Edition). UK Data Service. https://doi.org/10.5257/oecd/ims/2018-06

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The International Migration database presents data showcasing flows and stocks of the total immigrant population and immigrant labour force, together with data on acquisition of nationality.

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Start: 1941
End: 2017

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Thousands or Units

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Inflows and Outflows of foreign population by nationality (thousands):

OECD countries seldom have tools specifically designed to measure the inflows and outflows of the foreign population, and national estimates are generally based either on population registers or residence permit data. This note is aimed at describing more systematically what is measured by each of the sources used.

Flows derived from population registers (thousands):

registers can usually produce inflow and outflow data for both nationals and foreigners. To register, foreigners may have to indicate possession of an appropriate residence and/or work permit valid for at least as long as the minimum registration period. Emigrants are usually identified by a stated intention to leave the country, although the period of (intended) absence is not always specified.

When population registers are used, departures tend to be less well recorded than arrivals. Indeed, the emigrant who plans to return to the host country in the future may be reluctant to inform about his departure to avoid losing rights related to the presence on the register. Registration criteria vary considerably across countries (as the minimum duration of stay for individuals to be defined as immigrants ranges from three months to one year), which poses major problems of international comparison. For example, in some countries, register data cover a portion of temporary migrants, in some cases including asylum seekers when they live in private households (as opposed to reception centres or hostels for immigrants) and international students.

Flows derived from residence and/or work permits:

Statistics on permits are generally based on the number of permits issued during a given period and depend on the types of permits used. The so-called “settlement countries” (Australia, Canada, New Zealand and the United States) consider as immigrants persons who have been granted the right of permanent residence. Statistics on temporary immigrants are also published in this database for these countries since the legal duration of their residence is often similar to long-term migration (over a year). In the case of France, the permits covered are those valid for at least one year (excluding students). Data for Italy and Portugal include temporary migrants.

Another characteristic of permit data is that flows of nationals are not recorded. Some flows of foreigners may also not be recorded, either because the type of permit they hold is not tabulated in the statistics or because they are not required to have a permit (freedom of movement agreements). In addition, permit data do not necessarily reflect physical flows or actual lengths of stay since: i) permits may be issued overseas but individuals may decide not to use them, or delay their arrival; ii) permits may be issued to persons who have in fact been resident in the country for some time, the permit indicating a change of status, or a renewal of the same permit.

Permit data may be influenced by the processing capacity of government agencies. In some instances a large backlog of applications may build up and therefore the true demand for permits may only emerge once backlogs are cleared.

Flows estimated from specific surveys

Ireland provides estimates based on the results of Quarterly National Household Surveys and other sources such as permit data and asylum applications. These estimates are revised periodically on the basis of census data. Data for the United Kingdom are based on a survey of passengers entering or exiting the country by plane, train or boat (International Passenger Survey). One of the aims of this survey is to estimate the number and characteristics of migrants. The survey is based on a random sample of approximately one out of every 500 passengers. The figures were revised significantly following the latest census in each of these two countries, which seems to indicate that these estimates do not constitute an “ideal” source either. Australia and New Zealand also conduct passenger surveys which enable them to establish the length of stay on the basis of migrants’ stated intentions when they enter or exit the country.

Inflows of asylum seekers by Nationality:

Unit of measure used - Units.
All data are based on annual submissions.
Prior to 2003 data for the United Kingdom refer to number of cases, and not persons. All figures are rounded to the nearest multiple of 5.
Data for the United States for 2004-2006 is a combination of INS affirmative applications and EOIR defensive applications (INS=number of cases; EOIR=number of persons).
From 2003 on, data for France include unaccompanied minors.
Data for Serbia might include asylum-seekers from Serbia, Montenegro, Serbia and Montenegro, and/or FR Yugoslavia.

Stock of foreign-born population by country of birth:

Estimates by country of birth are not available. Therefore all data presented in the International Migration Database are observed numbers. Data in italic in Table A.1.4. of the publication International Migration Outlook are estimated. For details on sources for observed figures, refer to ® below. Legend: ® Observed figures; ? Estimates with the component method (CM) or with the parametric method (PM).

Two questions must be asked before examining stocks of immigrants in OECD countries: 1) Who is considered an “immigrant” in OECD countries, and 2) What are the problems related to international comparability?

Who is an immigrant?

There are major differences in how immigrants are defined. Some countries have traditionally focused on producing data on foreign residents (European countries, Japan and Korea) whilst others refer to the foreign-born (settlement countries, i.e. Australia, Canada, New Zealand and the United States). This difference in focus relates in part to the nature and history of immigration systems and legislation on citizenship and naturalisation.

The foreign-born population can be viewed as representing first-generation migrants, and may consist of both foreign and national citizens. The size and composition of the foreign-born population is influenced by the history of migration flows and mortality amongst the foreign-born. For example, where inflows have been declining over time, the stock of the foreign-born will tend to age and represent an increasingly established community.

The concept of foreign population may include persons born abroad who retained the nationality of their country of origin but also second and third generations born in the host country. The characteristics of the population of foreign nationals depend on a number of factors: the history of migration flows, natural increase in the foreign population and naturalisations. The nature of legislation on citizenship and the incentives foreigners have to naturalise both play a role in determining the extent to which native-born persons may or may not be foreign nationals.

Sources for and problems in measuring the immigrant population

Four types of sources are used: population registers, residence permits, labour force surveys and censuses. In countries that have a population register and in those that use residence permit data, stocks and flows of immigrants are most often calculated using the same source. There are exceptions, however, as some countries instead use census or labour force survey data to estimate the stock of the immigrant population. In studying stocks and flows, the same problems are encountered whether population register or permit data are used (in particular, the risk of underestimation when minors are registered on the permit of one of the parents or if the migrants are not required to have permits because of a free movement agreement). To this must be added the difficulty of purging the files regularly to eliminate permits that have expired.

Census data enable comprehensive, albeit infrequent analysis of the stock of immigrants (censuses are generally conducted every five to ten years). In addition, many labour force surveys now include questions about nationality and place of birth, thus providing a source of annual stock data. However, some care has to be taken with detailed breakdowns of the immigrant population from survey data as sample sizes can be small. Inevitably, both census and survey data may underestimate the number of immigrants, especially where they tend not to be registered for census purposes, or where they do not live in private households (labour force surveys generally do not cover those living in institutions such as reception centres and hostels for immigrants). Both these sources may detect a portion of the illegal population, which is by definition excluded from population registers and residence permit systems.

Acquisition of nationality by country of former nationality (unie of measure: Units):

Nationality law can have a significant impact on the measurement of the national and foreign populations. In France and Belgium, for example, where foreigners can fairly easily acquire the nationality of the host country, increases in the foreign population through immigration and births can eventually contribute to a significant rise in the population of nationals. On the other hand, in countries where naturalisation is more difficult, increases in immigration and births amongst foreigners manifest themselves almost exclusively as rises in the foreign population. In addition, changes in rules regarding naturalisation can have significant numerical effects. For example, during the 1980s, a number of OECD countries made naturalisation easier and this resulted in noticeable falls in the foreign population (and rises in the population of nationals).

However, host-country legislation is not the only factor affecting naturalisation. For example, where naturalisation involves forfeiting citizenship of the country of origin, there may be incentives to remain a foreign citizen. Where the difference between remaining a foreign citizen or becoming a national is marginal, naturalisation may largely be influenced by the time and effort required to make the application, and the symbolic and political value individuals attach to being citizens of one country or another.

Data on naturalisations are usually readily available from administrative sources. As with other administrative data, resource constraints in processing applications may result in a backlog of unprocessed applications which are not reflected in the figures. The statistics generally cover all means of acquiring the nationality of a country. These include standard naturalisation procedures subject to criteria such as age or residency, etc. as well as situations where nationality is acquired through a declaration or by option (following marriage, adoption or other situations related to residency or descent), recovery of former nationality and other special means of acquiring the nationality of the country).

Inflows of foreign workers by nationality (unit - thousands):

Most of the statistics published here are based on the number of work permits issued during the year. As was the case for overall immigration flows, the settlement countries (Australia, Canada, New Zealand and the United States) consider as immigrant workers, persons who have received a permanent immigration permit for employment purposes. In each of these four countries, it is also possible to work on a temporary basis under various programmes.

The data on European countries are based on initial work permits granted, which sometimes include temporary and seasonal workers. Some significant flows of workers may not be covered, either because the type of permit that they hold is not covered in these statistics, or because they do not need permits in order to work (free circulation agreements, beneficiaries of family reunification, refugees). Data for some countries may include renewals of permits. The administrative backlog in the processing of work permit applications is sometimes large (as in the United States, for example), so that the numbers recorded may bear little relation to the demand. The data may also cover initial entries into the labour market and include young foreigners born in the country who are entering the labour market.

Stock of foreign-born labour force by country of birth (unit - thousands)

The international comparison of “immigrant” workers faces the difficulties already mentioned earlier regarding the measurement of the overall stock of immigrants as well as to the use of different concepts of employment and unemployment.

For the European countries, the main difficulty consists in covering EU nationals, who have free labour market access in EU Member States. They are sometimes issued work permits, but this information is not always as readily available as for third-country nationals. Switzerland revised the sampling of its labour-force survey in order to compensate for the information that was no longer available on EU workers in registers of foreign nationals following the signature of free movement agreements with the European Union. These bilateral agreements enable employees who are holders of “EU/EFTA” permits to change their job or profession (professional mobility), and this change is not registered in the Central Register for Foreign Nationals, the usual source for statistics on the stock of foreign workers.

A simple enumeration of work permits granted may result in persons being counted more than once if the person has successively been granted two permits during the same reference period. On the other hand, holders of “permanent” residence permits allowing access to the labour market are not systematically covered, since the proportion of those who are actually working is not always known.

Another difficulty concerns the inclusion of the unemployed, the self-employed and cross border workers. In the statistics of workers, the unemployed are generally included, except when the source is work permit records and when permits are granted subject to a definite job offer. The self-employed and cross-border workers are much less well covered by the statistics. Data reference periods also vary, as they are generally the end of December for register data, and the end of the first quarter of the reference year for employment survey data.

Population registers (when the population in the labour force can be identified) and work permit files may show breaks in series when expired work permits are eliminated, when this is not done automatically, or when regularisation programmes are implemented. When these breaks occur, the analysis of the growth of the stock of foreign workers is significantly biased.

Click to expand Population & Scope
Click to collapse Population & Scope
Click to expand Statistical population
Click to collapse Statistical population

No data are presented on the native population, since the purpose of this database is to describe the immigrant population (generally the foreign born population). The information gathered concerns the flows and stocks of the total immigrant population and immigrant labour force, together with data on acquisition of nationality. The presentation of the series in a relatively standard format does not imply that the data have been fully standardised and are comparable at an international level, since few of the data sources used are specifically designed to record migration movements. Because of the great variety of sources used, different populations may be measured. In addition, the criteria for registering population and the conditions for granting residence permits, for example, vary across countries, which means that measurements may differ greatly even if a theoretically unique source is being used.

In addition to the problem of the comparability of statistics, there is the difficulty of the very partial coverage of illegal migrants. Part of this population can be counted through censuses. Regularisation programmes, when they exist, make it possible to account for a far from negligible fraction of illegal immigrants after the fact. In terms of measurement, this makes it possible to better evaluate the volume of the foreign population at a given time, although it is not always possible to classify these immigrants according to the year they entered the country.

Since the nature of the sources used differs considerably across countries, each series is provided with an explanatory note aimed at making it easier to understand and use the data presented.

Click to expand Concepts & Classifications
Click to collapse Concepts & Classifications
Click to expand Other Aspects
Click to collapse Other Aspects
International Migration DatabaseAbstract

The Organisation for Economic Co-operation and Development (OECD) International Migration Statistics include data on foreign and immigrant populations, foreign workers, migration flows and naturalisations for OECD member countries and others for a variety of periods from 1980 onwards.

This summary table contains data for 1980 onwards on the following variables: inflows and outflows of foreigners, asylum seekers, stocks of foreigners and foreign born, and naturalisations. Countries covered are: Australia, Austria, Belgium, Canada, Denmark, Finland, France, Germany, Greece, Ireland, Italy, Japan, Luxembourg, the Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, the United Kingdom, and the United States.

Contact person/organisation

Get in touchhttp://ukdataservice.ac.uk/help/get-in-touch.aspxData source(s) used

The International Migration database presents data showcasing flows and stocks of the total immigrant population and immigrant labour force, together with data on acquisition of nationality.

Direct source

Bibliographic citation:
Organisation for Economic Co-operation and Development: International Migration Statistics (June 2018 Edition). UK Data Service. https://doi.org/10.5257/oecd/ims/2018-06

Unit of measure used

Thousands or Units

Variables collected

Inflows and Outflows of foreign population by nationality (thousands):

OECD countries seldom have tools specifically designed to measure the inflows and outflows of the foreign population, and national estimates are generally based either on population registers or residence permit data. This note is aimed at describing more systematically what is measured by each of the sources used.

Flows derived from population registers (thousands):

registers can usually produce inflow and outflow data for both nationals and foreigners. To register, foreigners may have to indicate possession of an appropriate residence and/or work permit valid for at least as long as the minimum registration period. Emigrants are usually identified by a stated intention to leave the country, although the period of (intended) absence is not always specified.

When population registers are used, departures tend to be less well recorded than arrivals. Indeed, the emigrant who plans to return to the host country in the future may be reluctant to inform about his departure to avoid losing rights related to the presence on the register. Registration criteria vary considerably across countries (as the minimum duration of stay for individuals to be defined as immigrants ranges from three months to one year), which poses major problems of international comparison. For example, in some countries, register data cover a portion of temporary migrants, in some cases including asylum seekers when they live in private households (as opposed to reception centres or hostels for immigrants) and international students.

Flows derived from residence and/or work permits:

Statistics on permits are generally based on the number of permits issued during a given period and depend on the types of permits used. The so-called “settlement countries” (Australia, Canada, New Zealand and the United States) consider as immigrants persons who have been granted the right of permanent residence. Statistics on temporary immigrants are also published in this database for these countries since the legal duration of their residence is often similar to long-term migration (over a year). In the case of France, the permits covered are those valid for at least one year (excluding students). Data for Italy and Portugal include temporary migrants.

Another characteristic of permit data is that flows of nationals are not recorded. Some flows of foreigners may also not be recorded, either because the type of permit they hold is not tabulated in the statistics or because they are not required to have a permit (freedom of movement agreements). In addition, permit data do not necessarily reflect physical flows or actual lengths of stay since: i) permits may be issued overseas but individuals may decide not to use them, or delay their arrival; ii) permits may be issued to persons who have in fact been resident in the country for some time, the permit indicating a change of status, or a renewal of the same permit.

Permit data may be influenced by the processing capacity of government agencies. In some instances a large backlog of applications may build up and therefore the true demand for permits may only emerge once backlogs are cleared.

Flows estimated from specific surveys

Ireland provides estimates based on the results of Quarterly National Household Surveys and other sources such as permit data and asylum applications. These estimates are revised periodically on the basis of census data. Data for the United Kingdom are based on a survey of passengers entering or exiting the country by plane, train or boat (International Passenger Survey). One of the aims of this survey is to estimate the number and characteristics of migrants. The survey is based on a random sample of approximately one out of every 500 passengers. The figures were revised significantly following the latest census in each of these two countries, which seems to indicate that these estimates do not constitute an “ideal” source either. Australia and New Zealand also conduct passenger surveys which enable them to establish the length of stay on the basis of migrants’ stated intentions when they enter or exit the country.

Inflows of asylum seekers by Nationality:

Unit of measure used - Units.
All data are based on annual submissions.
Prior to 2003 data for the United Kingdom refer to number of cases, and not persons. All figures are rounded to the nearest multiple of 5.
Data for the United States for 2004-2006 is a combination of INS affirmative applications and EOIR defensive applications (INS=number of cases; EOIR=number of persons).
From 2003 on, data for France include unaccompanied minors.
Data for Serbia might include asylum-seekers from Serbia, Montenegro, Serbia and Montenegro, and/or FR Yugoslavia.

Stock of foreign-born population by country of birth:

Estimates by country of birth are not available. Therefore all data presented in the International Migration Database are observed numbers. Data in italic in Table A.1.4. of the publication International Migration Outlook are estimated. For details on sources for observed figures, refer to ® below. Legend: ® Observed figures; ? Estimates with the component method (CM) or with the parametric method (PM).

Two questions must be asked before examining stocks of immigrants in OECD countries: 1) Who is considered an “immigrant” in OECD countries, and 2) What are the problems related to international comparability?

Who is an immigrant?

There are major differences in how immigrants are defined. Some countries have traditionally focused on producing data on foreign residents (European countries, Japan and Korea) whilst others refer to the foreign-born (settlement countries, i.e. Australia, Canada, New Zealand and the United States). This difference in focus relates in part to the nature and history of immigration systems and legislation on citizenship and naturalisation.

The foreign-born population can be viewed as representing first-generation migrants, and may consist of both foreign and national citizens. The size and composition of the foreign-born population is influenced by the history of migration flows and mortality amongst the foreign-born. For example, where inflows have been declining over time, the stock of the foreign-born will tend to age and represent an increasingly established community.

The concept of foreign population may include persons born abroad who retained the nationality of their country of origin but also second and third generations born in the host country. The characteristics of the population of foreign nationals depend on a number of factors: the history of migration flows, natural increase in the foreign population and naturalisations. The nature of legislation on citizenship and the incentives foreigners have to naturalise both play a role in determining the extent to which native-born persons may or may not be foreign nationals.

Sources for and problems in measuring the immigrant population

Four types of sources are used: population registers, residence permits, labour force surveys and censuses. In countries that have a population register and in those that use residence permit data, stocks and flows of immigrants are most often calculated using the same source. There are exceptions, however, as some countries instead use census or labour force survey data to estimate the stock of the immigrant population. In studying stocks and flows, the same problems are encountered whether population register or permit data are used (in particular, the risk of underestimation when minors are registered on the permit of one of the parents or if the migrants are not required to have permits because of a free movement agreement). To this must be added the difficulty of purging the files regularly to eliminate permits that have expired.

Census data enable comprehensive, albeit infrequent analysis of the stock of immigrants (censuses are generally conducted every five to ten years). In addition, many labour force surveys now include questions about nationality and place of birth, thus providing a source of annual stock data. However, some care has to be taken with detailed breakdowns of the immigrant population from survey data as sample sizes can be small. Inevitably, both census and survey data may underestimate the number of immigrants, especially where they tend not to be registered for census purposes, or where they do not live in private households (labour force surveys generally do not cover those living in institutions such as reception centres and hostels for immigrants). Both these sources may detect a portion of the illegal population, which is by definition excluded from population registers and residence permit systems.

Acquisition of nationality by country of former nationality (unie of measure: Units):

Nationality law can have a significant impact on the measurement of the national and foreign populations. In France and Belgium, for example, where foreigners can fairly easily acquire the nationality of the host country, increases in the foreign population through immigration and births can eventually contribute to a significant rise in the population of nationals. On the other hand, in countries where naturalisation is more difficult, increases in immigration and births amongst foreigners manifest themselves almost exclusively as rises in the foreign population. In addition, changes in rules regarding naturalisation can have significant numerical effects. For example, during the 1980s, a number of OECD countries made naturalisation easier and this resulted in noticeable falls in the foreign population (and rises in the population of nationals).

However, host-country legislation is not the only factor affecting naturalisation. For example, where naturalisation involves forfeiting citizenship of the country of origin, there may be incentives to remain a foreign citizen. Where the difference between remaining a foreign citizen or becoming a national is marginal, naturalisation may largely be influenced by the time and effort required to make the application, and the symbolic and political value individuals attach to being citizens of one country or another.

Data on naturalisations are usually readily available from administrative sources. As with other administrative data, resource constraints in processing applications may result in a backlog of unprocessed applications which are not reflected in the figures. The statistics generally cover all means of acquiring the nationality of a country. These include standard naturalisation procedures subject to criteria such as age or residency, etc. as well as situations where nationality is acquired through a declaration or by option (following marriage, adoption or other situations related to residency or descent), recovery of former nationality and other special means of acquiring the nationality of the country).

Inflows of foreign workers by nationality (unit - thousands):

Most of the statistics published here are based on the number of work permits issued during the year. As was the case for overall immigration flows, the settlement countries (Australia, Canada, New Zealand and the United States) consider as immigrant workers, persons who have received a permanent immigration permit for employment purposes. In each of these four countries, it is also possible to work on a temporary basis under various programmes.

The data on European countries are based on initial work permits granted, which sometimes include temporary and seasonal workers. Some significant flows of workers may not be covered, either because the type of permit that they hold is not covered in these statistics, or because they do not need permits in order to work (free circulation agreements, beneficiaries of family reunification, refugees). Data for some countries may include renewals of permits. The administrative backlog in the processing of work permit applications is sometimes large (as in the United States, for example), so that the numbers recorded may bear little relation to the demand. The data may also cover initial entries into the labour market and include young foreigners born in the country who are entering the labour market.

Stock of foreign-born labour force by country of birth (unit - thousands)

The international comparison of “immigrant” workers faces the difficulties already mentioned earlier regarding the measurement of the overall stock of immigrants as well as to the use of different concepts of employment and unemployment.

For the European countries, the main difficulty consists in covering EU nationals, who have free labour market access in EU Member States. They are sometimes issued work permits, but this information is not always as readily available as for third-country nationals. Switzerland revised the sampling of its labour-force survey in order to compensate for the information that was no longer available on EU workers in registers of foreign nationals following the signature of free movement agreements with the European Union. These bilateral agreements enable employees who are holders of “EU/EFTA” permits to change their job or profession (professional mobility), and this change is not registered in the Central Register for Foreign Nationals, the usual source for statistics on the stock of foreign workers.

A simple enumeration of work permits granted may result in persons being counted more than once if the person has successively been granted two permits during the same reference period. On the other hand, holders of “permanent” residence permits allowing access to the labour market are not systematically covered, since the proportion of those who are actually working is not always known.

Another difficulty concerns the inclusion of the unemployed, the self-employed and cross border workers. In the statistics of workers, the unemployed are generally included, except when the source is work permit records and when permits are granted subject to a definite job offer. The self-employed and cross-border workers are much less well covered by the statistics. Data reference periods also vary, as they are generally the end of December for register data, and the end of the first quarter of the reference year for employment survey data.

Population registers (when the population in the labour force can be identified) and work permit files may show breaks in series when expired work permits are eliminated, when this is not done automatically, or when regularisation programmes are implemented. When these breaks occur, the analysis of the growth of the stock of foreign workers is significantly biased.

Reference period

Start: 1941
End: 2017

Statistical population

No data are presented on the native population, since the purpose of this database is to describe the immigrant population (generally the foreign born population). The information gathered concerns the flows and stocks of the total immigrant population and immigrant labour force, together with data on acquisition of nationality. The presentation of the series in a relatively standard format does not imply that the data have been fully standardised and are comparable at an international level, since few of the data sources used are specifically designed to record migration movements. Because of the great variety of sources used, different populations may be measured. In addition, the criteria for registering population and the conditions for granting residence permits, for example, vary across countries, which means that measurements may differ greatly even if a theoretically unique source is being used.

In addition to the problem of the comparability of statistics, there is the difficulty of the very partial coverage of illegal migrants. Part of this population can be counted through censuses. Regularisation programmes, when they exist, make it possible to account for a far from negligible fraction of illegal immigrants after the fact. In terms of measurement, this makes it possible to better evaluate the volume of the foreign population at a given time, although it is not always possible to classify these immigrants according to the year they entered the country.

Since the nature of the sources used differs considerably across countries, each series is provided with an explanatory note aimed at making it easier to understand and use the data presented.

Key statistical concept

OECD Migration web pageshttp://www.oecd.org/migration/Classification(s) used

The sources and methods used to compile the DIOChttp://www.oecd.org/els/mig/40136955.pdfInternational Migrants in Developed, Emerging and Developing Countries: An Extended Profilehttp://www.oecd.org/migration/46535003.pdfRecommended uses and limitations

Guide to OECD International Migration Statisticshttp://ukdataservice.ac.uk/use-data/guides/dataset/migration-statistics.aspxOther comments

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Organisation for Economic Co-operation and Development

Terms and Conditionshttp://www.oecd.org/termsandconditions/