WASHINGTON, D.C. -- Although a recent United Nations report estimates about 214 million migrants have moved between countries, Gallup studies show a much larger number of migrants are moving within countries. Eight percent of the world's adults -- roughly 381 million people -- say they have moved from one city or area within their country to another in the past five years.

Compared with the data available on migrants who move between countries, global estimates on the number of migrants who move within countries have so far been difficult to reach because of the lack of reliable global data and cross-national measures. Between 2011 and 2012, Gallup uniformly asked 236,865 adults in 139 countries whether they had moved from another city or area within their country in the past five years. These 139 countries represent more than 97% of the world's adult population, enabling a reliable global estimate.

Internal migration rates range widely from more than 21% in places such as New Zealand and the United States to less than 5% in countries such as China and Venezuela. The data also confirm commonly held beliefs, including that the U.S. is one of the most mobile countries in the world. About one in four U.S. adults (24%) reported moving within the country in the past five years -- similar to rates reported in other advanced economies such as New Zealand (26%), Finland (23%), and Norway (22%).

Educated, Young More Likely to Have Migrated Internally in Past Five Years

Migration is often associated with the search for better educational opportunities, and across most regions, adults with higher education are more likely to be internal migrants. Worldwide, those with at least a college education are more than twice as likely (13%) to say they moved internally in the past five years as those with primary education or less (5%). In some regions, such as the Commonwealth of Independent States (CIS), there is no evidence of an education effect, but the education differences are more dramatic in other areas such as sub-Saharan Africa.

Overall, young adults are most likely to be internal migrants. Worldwide, 10% of adults between the ages of 15 and 29 report moving within their country in the past five years. By age 50, this likelihood is half as high (5%). In several regions, such as the European Union, the likelihood to migrate internally starts declining after age 29, but in other areas, such as Latin America, it does not start to drop off until after age 49.

Internal Migrant Employment Status Varies by Region

While the global economic picture looks different from region to region, so too does the employment picture for internal migrants. In Northern America, for example, internal migrants are more likely to participate in the workforce than those who have not moved. However, internal migrants are no more likely to be employed full time for an employer. They are more likely to be underemployed or unemployed than those who have not moved. Underemployment and unemployment among those in the workforce are higher for internal migrants in Latin America, the EU, and Australia/New Zealand.

Internal Migrants More Likely to Send and Receive Financial Help

Not only are many internal migrants gainfully employed and participating in the economy, they are more likely than their "rooted" counterparts to provide financial help to others inside the country and abroad. At the same time, internal migrants are also more likely to receive financial help from within the country and abroad. But internal migrants are more likely to send financial help than receive it, while this difference is not that pronounced among those who have not moved.

These results reinforce how internal migration can be as important as or even more important than international migration is to poverty-reduction strategies. There are more internal migrants than international migrants on the move worldwide, and they are more inclined to send financial help home. However, while global estimates of the size of internal remittances do not exist, additional global Gallup research shows households worldwide are three times more likely to get financial help from individuals within the same country (9%) than from outside the country (3%).

Bottom Line

The relationship between migration and remittances is one reason why migration -- within countries or across international borders -- will continue to be an important item on the post-2015 Millennium Development Goals discussion agenda. However, compared with the data available on international migrants, the development of global estimates of internal migrants is still in its nascent stages. Further research and measurement is needed for policymakers to investigate the potential implications of the most common type of migration.

This article is excerpted from a longer piece that appears in the April-May edition of the "Migration Policy Practice Journal."

For complete data sets or custom research from the more than 150 countries Gallup continually surveys, please contact us.

Survey Methods

Results are based on 236,865 adults, aged 15 and older, conducted in 2011 and 2012 across 139 countries and areas. The typical sample size for each country is between 1,000 and 3,000 interviews. Sample sizes are higher in some countries; for example, more than 10,000 interviews in China and in India and 5,000 interviews in Russia. In three countries, sample sizes were approximately 500: Haiti, North Cyprus, and Suriname. For results based on the total sample of national adults, one can say with 95% confidence that the margin of sampling error ranges from a low of ±1.2 percentage points to a high of ±5.2 percentage points.

For more complete methodology and specific survey dates, please review Gallup's Country Data Set details.