Summary
The recession-induced decline of undocumented migration from Mexico appears to have stopped in the first half of 2012 amid tentative signs of a renewed northbound flow, according to new data from the Border Survey of Mexican Migration (EMIF) administrated by El Colegio de la Frontera Norte.
The survey data, consistent with other indicators cited in this report, show that the number of undocumented migrants heading into the United States declined steadily for four years starting at the beginning of 2008 but that the pace slowed in 2011 and then reversed. In the first two quarters of 2012, the border survey registered annual gains in the undocumented flow for the first time since the onset of the Great Recession.
Although the numbers are still small and the time frame is short, the survey data from 2012 suggest that the overall flow of migrants from Mexico to the United States has substantially adjusted to the combined effects of the economic downturn, heightened U.S. immigration enforcement efforts, and a wave of criminal violence in Mexico’s border region. More Mexicans are coming north and fewer of those already in the United States are heading back south, according to an analysis of the survey data that is supported by indicators drawn from official sources.
With indicators pointing to a stable or increasing northbound flow and a decreasing southbound flow, the data available through mid-2012 suggest that the net flow could move into positive territory again with any uptick of demand in the U.S. labor market.
The Data
Operating since 1993, the Border Survey of Mexican Migration is the oldest continuous research program tracking original data on the number of people crossing the U.S.-Mexico border legally or illegally. Click here for more information on the survey. The Encuesta sobre Migración en la Frontera Norte de México (EMIF) is conducted in selected border-crossing points and at airports in the interior of Mexico by El Colegio de la Frontera Norte (COLEF), a government-funded social science research institution whose main campus is in Tijuana. EMIF’s data collection is sponsored by COLEF and several ministries and agencies of the Mexican federal government.
In this report we are primarily concerned with changes in the size of migration flows over time, and the border survey is particularly valuable in this regard because the methodology has been repeated consistently over many years. Our intent is to depict trends in the volume of migration that will show increases or decreases in the flow of, for example, how many Mexicans entered the United States, across several years. Moreover, EMIF’s sampling design allows flows to be tracked by calendar quarters. Annual comparisons for the same quarter allow analyses that account for seasonal variations in the flow. Conducted in Mexico by Mexican interviewers, the survey asks northbound respondents whether they are crossing into the United States legally or not.
Definition of EMIF’s Flows
- Northbound Flow to the United States: Survey respondents who are Mexican-born individuals 15 years of age or older, arriving at Mexico’s northern border region who reported that they intend to cross to the United States and are not residents of Mexican border cities or the United States.
- Southbound Flow from the United States: Survey respondents who are Mexican-born individuals 15 years of age or older, leaving Mexico’s northern border region who reported working or making their home in the United States or visiting for more than a month for other purposes such as visiting relatives.
Findings
Unauthorized migrants almost uniformly travel in search of work, and the contraction of the U.S. labor market has coincided with a major decline in that flow. Since the first quarter of 2008, unauthorized flows from Mexico to the United States posted 16 straight quarters of decreasing volume on an annualized basis, according to data from the Border Survey of Mexican Migration. The pace of decline began to slow in the second half of 2010, and in the first two quarters of 2012 the flow marked small gains compared with the previous year.
In the first quarter of 2012, the survey registered an unauthorized flow 42 percent higher than in same quarter of 2011. The second quarter marked a year-over-year increase of 14 percent (Figure 1). Six months of modestly higher volumes might not be notable except that the trend had been solidly in the opposite direction for four years.

Another indicator of a renewed unauthorized flow comes from the share of northbound travelers who report that they intend to cross the border illegally. In 2006, at the height of the pre-recession surge of Mexican migration, the unauthorized accounted for about eight of every ten northbound migrants (Figure 2). As the U.S. economy collapsed, that share dropped until the unauthorized were less than half of the flow. The trend started showing signs of a reversal in the middle of 2011. Since the fourth quarter of 2011, the share of the unauthorized in the northbound flow has held steadily at 60 percent or more for three consecutive quarters.

Assessing the total northbound flow, both unauthorized and otherwise, shows that overall Mexican migration into the United States surged in the mid-2000s and reached some the highest flows ever measured in 2006 and 2007 with peak flows of about 200,000 new migration events per quarter. (The boom year of 2000 is the prime contender for the all-time record.) So, what happened after 2007 needs to be understood as a comedown from a peak. And it was a temporary and somewhat artificial peak to the extent that migration was pumped up by the home construction bubble and other economic activities in the United States that proved subject to collapse and slow to recover.
Figure 3 takes the peak northbound flow in the border survey in the first quarter of 2006 as a benchmark and uses quarterly data to illustrate the volume building up to that peak and then coming down from it. The survey data show that after a sharp slide over the course of three years, the volume of flows in 2010 was comparable to where it had been three years prior to the peak. The contraction in migration continued, however, and by mid-2011 the volume had shrunk roughly to a third the size of its pre-recession high.
Over the past year—from the second quarter of 2011 to the second quarter of 2012—a new trend seems to be developing in the northbound flow. For the past five quarters, the border survey data have held relatively steady, albeit at levels that are a fraction of what was recorded even a few years ago. The current picture is of stability at a much-reduced volume.
A similar analysis in Figure 4 shows that the recession had a short and sharp impact on the southbound flow. In this case the effects of the downturn start to become evident in 2007, and the southbound flow reaches a peak in the fourth quarter of 2009. The number of Mexicans leaving the country then started to decrease. Since 2010, the southbound flow has held close to its pre-recession levels in the border survey. The data available for 2012 suggest that the number declined further.
The decline in the number of Mexicans leaving the United States could be the result of many factors such as perceptions that the U.S. economy has stabilized. Paradoxically, the reduction in the number of migrants moving north also could have an impact on this indicator because there is a certain degree of circular migration—the same people moving back and forth between the two countries.
For purposes of this report, the most important finding is that the number of southbound migrants has been declining steadily for two and a half years. That period coincides with several new or intensified U.S. immigration enforcement efforts. These include the enactment of several state laws designed to penalize unauthorized migrants and a vigorous deportation campaign by the Obama administration. Neither the border survey nor the other indicators examined here offers any evidence that those efforts have had any effect on the number of Mexican migrants leaving the country. On the contrary, fewer Mexican migrants have left the United States since those enforcement efforts went into effect, and the stock of Mexican-born immigrants in the United States has remained stable (see article on demographic trends in this report).



