How many migrants are making it successfully over the border?

We know how many migrants are apprehended trying to make it over the border illegally, but how many actually make it across successfully?

As it turns out, this is not an easy calculation.  Notwithstanding, we forecast successful, illegal entry into the US across the southwest border in calendar year 2019 at 260,000 - 500,000, assuming 70% and 55% apprehension rates, respectively.


Assumed apprehension rates in the literature cover the spectrum, from 20% to 90%.   Surveys conducted by the Mexican Migration Project, a collaboration of Princeton and Guadalajara Universities, suggest that apprehension rates have never risen above 40%.  This 40% rate is historically consistent with a 2017 DHS study until 2013, after which the rate rises to the 55% which we have used in most of our analyses  (see page 8).  I have heard rates of 70% recently from experts in the field, and while I consider this the high end of plausible, I am inclined to stay closer to our lower number.

To understand why a 55% rate seems more reasonable, we have to consider how migrants think about jumping the border.  They do not try just once, and having failed, simply give up.  For migrants, there is huge difference between success and failure.  We estimate the all-in, risk-adjusted cost of a crossing at $12,000, of which $4,000 or more will be the coyote fee.  Even in Mexico, $4,000 represents almost two years' wages, and in the Northern Triangle countries, it effectively constitutes one's life savings. If one makes it to the US, the payback period, by our estimation, is 6-9 months, not too bad all things considered.  If one fails, the setback will last many years.  Taking a shot at a border is a big decision, and migrants have every incentive to persist once they have elected to try a crossing.  Therefore, in many cases, if migrants are caught and deported, they try again, and perhaps a third time.  

I have heard reports of coyotes guaranteeing up to three tries for their fee, which suggests that almost everyone gets through upon the third attempt.  At a 70% apprehension rate, that just would not happen.  Indeed, about 40% of attempted crossers would never make it through, and that's a big deal.  If 40% of crossers lost their life savings--the number consistent with a 70% apprehension rate--we should see many related stories in the press, and none pops up.  This leads us to believe that most migrants are still making it across, at substantial expense and with a couple of tries, but they are still making it through.  

The border apprehensions data below also suggests greater ease in crossing the border.  In 2016, for example, apprehensions hit multiyear highs in the run-up to the US presidential election.  Migrants were worried about a Trump victory and accelerated their crossings before the election -- and then deferred them once Trump took office.  Similarly, in the last half year or so, the pace of apprehensions has accelerated rapidly, presumably due to strength in the US economy.  The data are suggestive of a fluid and well-functioning market able to react on a few weeks' or months' notice to changing economic conditions.   The numbers do not feel, from the analyst's perspective, like a market in which 40% of the crossers are wiped out.

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Consequently, while a 70% apprehension rate cannot be precluded, the available data suggest a rate in the 55-58% range is more likely.  (In the interest of completeness, I would also note that a 40% apprehension rate is also unlikely, as it would imply that 660,000 migrants made it through successfully to the US in 2016.  Such a high number is incompatible with undocumented immigrant estimates from Pew Research.)  

If we accept a 55% apprehension rate, then 80% of migrants make it through, trying an average of 1.8 times for a successful crossing.  This, incidentally, is consistent with Border Patrol claims that, "on most of the border, you're looking at a 90 percent-plus apprehension rate, meaning if you cross that southwest border unlawfully, over 90 percent chance you're being apprehended."  Our analysis suggests that's actually true statistically (apprehensions/number of persons attempting a crossing), but it is also consistent with 80% of migrants making it through within three tries (see the 'Apprehensions' tab in our updated Migrant Predation and Victimization spreadsheet for the model and math).

Why are the migrants coming in such numbers?

JOLTS, a monthly survey of the US job market prepared by the US Bureau of Labor Statistics, provides insight.  The JOLTS numbers are just as stunning as border apprehensions data in the last few months.  Since the Republican tax cut took effect, the number of jobs openings has soared, but hires have failed to keep pace.  As a result, JOLTS is showing a record excess of openings over hires.  Moreover, quits are also running near record levels as incumbent employees leave for better paying jobs in more senior positions.  Together, these suggest a vast number of open positions at the low end of the wage scale -- exactly the niche covered by undocumented migrants.  In fact, our analysis on a segment-by-segment basis suggests there may be 2 million open US jobs in the unskilled migrant category.  That's why they are coming, and even at a 500,000 / year pace, it would take years to fill available openings.   This suggests apprehensions, and by extension illegal entry into the US, may well run hot this year, and indeed, might rival some of the go-go years of the Clinton administration prospectively.


Does this constitute an 'emergency'?  The President is arguably correct that migrant numbers are increasing rapidly, and, if we allow this year's forecast of 500,000 new entrants, are material in magnitude.  Moreover, both business cycle factors and underlying US demographics suggest the trend is likely to persist.

On the other hand, migrants are here to provide goods and services which Americans require -- hence the job openings.  

The question, therefore, appears to be more about the conditions of migrants' presence than the actual fact of it.  Americans are right to worry about millions of undocumented aliens roaming the country; the lack of order, transparency and safety in the migrant labor market; the impact of so many low income migrants on US political and governance culture; and the burden they may represent to the US taxpayer.  All these are legitimate concerns, but we do not need a wall to resolve them.  All these issues can be addressed, quickly and effectively.  It's not that hard to do, if leadership is willing to implement those policies which have worked in the past.