Border Patrol agents apprehended more than four million migrants who illegally crossed the southwest border with Mexico during the past 10 fiscal years. If these migrants were placed into a single city, it would be larger than Los Angeles by population.

During the past 10 fiscal years, October 1, 2009, through September 30, 2019, U.S. Border Patrol agents assigned to the nine sectors that make up the United States’ southwest border with Mexico apprehended 4,318,200 migrants. The highest year during that decade for apprehensions occurred during Fiscal Year 2019 when agents apprehended 851,553 — including 76,020 Unaccompanied Alien Children (UAC) and 473,682 Family Unit Aliens (FMUA), according to reports obtained from U.S. Customs and Border Protection.

Apprehensions by Fiscal Year:

FY2019 — 851,553

FY2018 — 396,579

FY2017 — 303,916

FY2016 — 408,870

FY2015 — 331,333

FY2014 — 479,371

FY2013 — 414,397

FY2012 — 356,873

FY2011 — 327,577

FY2010 — 447,731

During the past decade, Rio Grande Valley (RGV) Sector Border Patrol agents apprehended the largest numbers of migrants. Between fiscal years 2010 and 2019, RGV Sector agents apprehended 1,600,663 migrants who illegally crossed the border into South Texas, the reports state.

Agents assigned to the Tucson Sector had the second-highest number of total apprehensions — 946,948. The Big Bend Sector in West Texas had the lowest number of total apprehensions — 56,149.

The report shows a shifting in migration traffic during the past decade. In FY2010, the Tucson Sector reported the highest number of apprehensions — 212,202. This changed in FY2013 when the largest apprehension numbers shifted to the RGV Sector.

In Fiscal Year 2019, RGV agents apprehended 339,135 migrants including 34,523 UACs and 211,631 FMUAs.

During the past 10 fiscal years, Border Patrol agents apprehended a total of 433,216 unaccompanied minors. Officials reported that more than half of those apprehensions, 235,050 took place in the RGV Sector.

FMUA apprehension numbers for the decade were not readily available. U.S. Customs and Border Protection officials provided statistics for Fiscal Years 2013 through 2019. During that period, Border Patrol agents apprehended 857,328 family units. More than half of these, 463,811, occurred in the RGV Sector.

FMUA apprehensions represent the largest increase in migrant demographics. The number of apprehensions jumped from 14,855 in FY2013 to 473,682 in FY2019 — an increase of more than 3,000 percent. Again, more than half of the FMUA apprehensions occurred in the RGV Sector — 463,811.

With three fiscal years missing from the FMUA report, FMUA and UAC apprehensions account for 1.3 million of the total 4.3 million apprehensions. These demographics also represent the highest cost to U.S. taxpayers in terms of processing, transporting, feeding, and providing healthcare, Border Patrol officials repeatedly state.