Migration data were released by the United Nations in September 2013. The data contain population counts for all possible destinations of international migrants for every origin country in the world (and vice versa, a population estimate for all origins of every destination country) in 1990, 2000, 2010 and 2013. Consequently, the data provide an estimate for the number of international migrants born in and currently living in every country of the world.

Estimates for the origins of migrants in this report include unknown origins, which together amount to more than 3 million people in 2013, or about 1% of all the world’s international migrants.

Also, the U.N.’s migration data released in September 2013 included updates to previous years. As a result, migrant estimates in this report differ from estimates in other reports on international migration published by the U.S. Census Bureau and the Pew Research Center.

Remittance inflow data from 2000 to 2013 were drawn from the World Bank. Estimates for 2013 are forecast by the World Bank based on previous trends and projected economic conditions in destination countries. When reporting trends over time in remittance flows, amounts for years before 2013 are adjusted to 2013 dollars, using the average U.S. inflation rate for every preceding year. For this reason, some numbers in this report differ from unadjusted data published by the World Bank. Also, trends contain complete information for countries across all years, amounting to 93% of total inflow in 2013. A total of 137 countries were used for trends.

The World Bank reports only remittances sent via formal channels, such as banks and other businesses that transfer money. If unofficial remittances were counted, the total could be 50% higher or more, according to household surveys and other evidence cited by the World Bank.

In 2013, the World Bank revised its definition of remittances to delete a category of capital transfers between households. The World Bank also revised previously published numbers back to 2005 to reflect the change. Therefore, there is some discontinuity in the remittance data in this report for 2000 to 2004 and data for 2005 onward. Nevertheless, overall patterns are similar regardless of whether the new definition is used.

Economic Classifications and Regions

Economic classifications follow the taxonomy provided by the World Bank in their categorization of countries in October 2013. Lower-income countries have a per capita gross national income (GNI) of $1,035 U.S. dollars or less. Examples of lower-income nations are Afghanistan and Zimbabwe. Middle-income countries have a per capita GNI between $1,036 and $12,615 U.S. dollars and include lower-middle nations such as Bolivia and Pakistan, and upper-middle countries such as Brazil and China. Finally, high-income nations have a per capita GNI of $12,616 U.S. dollars or more and include such countries as the United States and Russia. See Appendix B for a complete list of countries by their economic classification.

The great majority of countries remained in the same high-, middle-, or lower-income positions since 1990. Major exceptions include China (changed from low income to middle income in 1999), India (changed from low income to middle income in 2007) and Russia (changed from middle income to high income in 2012). However, even if these countries are excluded from the analysis, the patterns are similar. Additional analysis indicates that economic shifts in migration patterns are not due entirely to changing classification of countries. When the World Bank’s 1990 classification of countries is substituted for the 2013 classification, the patterns also are similar, even though the numbers of countries in the high- and middle-income groups have increased since 1990.

Geographic regions used in this report for the most part match regions categorized by the U.N. One exception is the added Middle East-North Africa region, which consists of countries in North Africa along the Mediterranean, Gulf Cooperation Council countries, Israel and nearby countries as far east as Iraq. Sudan is also part of the Middle East-North Africa region, while Turkey and Iran are considered part of the Asia-Pacific region. See Appendix C for a complete list of countries by their regional classification.


The percent immigrant calculation for 1990, 2000 and 2010 uses the number of immigrants estimated by the U.N. in these years divided by the total population in these countries also estimated by the U.N. The percent immigrant calculation for 2013 is from the U.N.’s Migration Wallchart.

The percent emigrant calculation was computed for 1990, 2000 and 2010. The numerator is the number of people living outside of their country of birth. The denominator is the total population estimated by the U.N. for the birth country plus the number of people born in the birth country but living in a foreign country minus the number of foreign-born people living in the birth country.

Because smaller nations can have unique explanations associated with these calculations, countries with a total population less than 1 million are excluded from the rankings included in this report. Moreover, the Palestinian territories are not included for the percent emigrant since the U.N. includes descendants into the third and fourth generations. Consequently, these migrant counts are not consistent with the foreign-born definition used in this report.

The percent of GDP calculation is the total remittances received by a country divided by the country’s GDP for that particular year.