Last year I published a small app that uses ACS data to measure how US counties have changed since Covid: https://census-explorer.streamlit.app/. I think I posted here when I released the app.
I recently made some updates to the app, and wrote a blog post about the changes. I thought that people here might be interested in that post as well: https://arilamstein.com/blog/2025/06/02/new-release-covid-demographics-explorer-v2/
Of particular interest, I think, might be the use of a "Swarm Plot" to compare how all counties changed between 2019 and 2023 (i.e. the year right before Covid, and the last year of available data). Here is the swarm plot of percent population change of all counties in the ACS 1 dataset. Note that San Francisco is highlighted (in the app, users can select a county to highlight):
Each dot represents a circle. Its position on the x-axis indicates the percent change it experienced. Here you can that San Francisco (where I live) had an unusually large decrease in population. This visualization is useful because sometimes a county experiences a large change, but it's completely explainable as part of a larger trend (such as the increase in the number of people who work from home).
My post goes into more detail: https://arilamstein.com/blog/2025/06/02/new-release-covid-demographics-explorer-v2/