President Trump has repeatedly criticized the Mexican government for failing to do more to stop the Central American migrants heading north to the United States through Mexico. He tweeted yesterday, “They have ALL been taking U.S. money for years, and doing ABSOLUTELY NOTHING for us, just like the Democrats in Congress!” The truth is more complex. The Mexican government is doing a lot in absolute terms, but its efforts have become relatively less effective over time.

Figure 1 shows the number of apprehensions and deportations of Central Americans from the Northern Triangle by U.S. fiscal year from 2001 to 2019. As it shows, enforcement activity in Mexico peaked during the period in the mid-2000s. It declined from 2006 to 2011, briefly surged in 2015 and 2016, before declining again. The deportation rate has fluctuated year-to-year, but has also fallen from 99% to 83% from 2017 to 2019.

Figure 2 shows the number of apprehensions of Central Americans in Mexico and the U.S. Border Patrol from FY 2001 to FY 2019. As it shows, Mexico interdicted the vast majority of Central Americans traveling north in the early 2000s. In 2001, it apprehended eight Central Americans from the Northern Triangle for each that made it to the U.S. southwest border. That rate declined each year through 2014 before improving in 2015 and falling each year thereafter. In 2019, nearly four Central Americans will reach U.S. soil for each apprehended in Mexico. Mexico’s share of total apprehensions fell from 89 percent to an estimated 21 percent in 2019.

The Mexican government’s immigration agency—the Instituto Nacional de Migración (INM)—spent $74 million more in 2011 than 2017 (calendar years), increasing expenditures from $200 million to $274 million—a 27 percent jump. Strangely, during this time, the actual formal budget for the INM fell by two thirds. The formal budget is what the federal government appropriates, while the INM has other sources of spending from fees on visas and possibly other sources. It is worth noting that Mexico’s military also engages in immigration enforcement activities, and the federal police force also participates to some extent.

Focusing solely on the period for which we have data, Mexico improved its efficiency in apprehensions per dollar spent from 2011 to 2016 (Figure 4). This metric regressed in 2017 following a fall in apprehensions (driven by a smaller flow). The INM spent $2,841 per apprehension, though it is important to note that this isn’t the amount spent specifically on each apprehension. Rather, it is the total spending divided by total apprehensions.

In a development related to its enforcement efforts, the Mexican government created visitor and work visa programs for Guatemala in 2008. They created a humanitarian visa for all Central Americans in 2013 and their asylum program has also expanded rapidly in importance. These avenues (annualized) grew strongly so far in FY 2019 (Figure 5). Total participants in one of these legal immigration program has increased from 106,351 in 2017 to be on pace for 175,272 through January of 2019. Just like in the United States, an asylum application can stop a removal, which may explain the decline in the deportation rate from 2017 to 2019.

Mexican immigration enforcement has changed significantly over the last two decades. Immigration enforcement spending has increased, but apprehensions and deportations are not at record highs and the deportation rate has declined in the last two years. Moreover, Mexico’s interdiction rate of Central Americans fell greatly since 2001, even prior to the increases in total flows. This could possibly be related to the increased number of Central Americans who enter Mexico legally and travel with legal status to the U.S. border.

While the Mexican government is increasing enforcement to new levels in recent weeks, it has not shown so far that it can stop enough of the flow to disincentivize future migration of Central Americans.