I just created a web app for exploring trends in the foreign-born population in the United States. The app lets you pick a location and see how the size of the foreign-born population there has changed over time. A core purpose of the project is to let people track how the foreign‑born population changes as new immigration enforcement policies are implemented.
The app is built in Python with Streamlit, and the data comes from the American Community Survey (ACS) 1‑year estimates. Everything is powered by the acs‑nativity package I recently published to PyPI. The ACS currently covers 2005–2024, and the 2025 release is expected in September — I’ll update the app as soon as the new data becomes available. Data is available for the nation, all states, and any county or city with at least 65,000 residents.
Here’s a screenshot from the app providing data on Chicago, Illinois:
Chicago’s foreign‑born population has risen and fallen sharply at different points between 2005 and 2024. Last September President Trump launched an immigration enforcement action in the city called Operation Midway Blitz. When the 2025 ACS estimates come out in September, we’ll get the first chance to see whether that enforcement action shows up in the data – and how any change compares with the kinds of fluctuations Chicago has experienced in the past.
Exploratory Data Analysis
In addition to the graphs generated by the acs-nativity package, the app provides two additional tabs to help you explore nativity trends: the Table tab and the Compare Years tab.
Table Tab
The Table tab shows the full dataset for the selected geography level, and you can sort by any column. Sorting makes it easy to spot outliers. For example, in 2024 the location with the highest share of foreign‑born residents was Hialeah, Florida (77.1%), while the lowest was Muskingum County, Ohio (0.7%):
Compare Years Tab
The Compare Years tab lets you create a table showing how a demographic has changed between two years. This often surfaces surprising results. For example, between 2023 and 2024, New York City saw an estimated increase of 205,767 in the Native-born population – slightly larger than California’s increase of 204,056, despite California’s population being several times larger:
Try the App
If you’re interested in how these patterns play out in your own community, you can explore the app here.
