How the data works

If you spot something wrong, please let me know.

What the map shows

The particle map combines data from multiple US government sources. Each dot represents roughly 300 people. The data is layered by how people arrived: legal admissions through ports of entry, border encounters recorded by CBP, visa overstays estimated by DHS, and “gotaways” (known but unapprehended crossings) from CBP operational data and congressional testimony.

These are distinct populations. Border encounter data (CBP) measures crossings. Settlement data (Census ACS) measures where foreign-born people live. Admission category data (USCIS) measures how people were legally classified. Each tells a different part of the story.

Settlement destinations

Where dots land on the map is based on Census ACS foreign-born population data, weighted by region-of-origin affinities. For example, Mexican-origin dots are more likely to settle in Texas, California, and Illinois because that matches the actual settlement patterns in ACS data. The scatter radius is randomized within metro areas for readability.

Gotaway estimates

The “uncounted” layer uses known gotaway figures from CBP operational data shared in congressional briefings and testimony. CBP does not officially publish these numbers; they originate from internal dashboards reported by news outlets and confirmed in hearings (notably Border Patrol Chief Raul Ortiz’s Senate Judiciary Committee testimony in May 2023). Monthly values are weighted by seasonal border crossing patterns.

Economic data

The economic sections draw from published research by the Congressional Budget Office, Brookings Institution, Peterson Institute for International Economics, Cato Institute, Economic Policy Institute, ITEP, and others. Each figure is cited inline and linked to its source where available.

Caveats

• Encounter counts include repeat crossings; the same individual may be counted multiple times.
• ACS foreign-born estimates lag by approximately two years and include all foreign-born residents regardless of immigration status.
• USCIS admission categories cover lawful permanent residents only, not temporary workers or undocumented individuals.
• Gotaway figures are approximate. By definition they exclude people who crossed without being detected at all.