Follow the flow › Step 1 of 16 · Money path
1. People & ZIP codes
Everything starts with people. A ZIP code is a small area where people live. The Census counts how many people live there, how old they are, how many homes there are, and how much they earn. These people pay the taxes and cast the votes that run the whole system.
Who holds the money or the vote here?
Nobody holds money yet. The people in each ZIP hold their own money and their own votes.
How often does it happen?
Census count every 10 years; the American Community Survey (ACS) updates every year (5-year averages for small areas like ZIPs).
Where the records come from
Federal data is the same for everyone. When you pick a state, the state and local rows are the places to look for your state. "Have now" means PSI Sci already collects it; "Planned" means we list the source but do not collect it yet.
| Level | Source | Format | How often | On PSI Sci |
|---|---|---|---|---|
| Federal | Census ACS 5-year, ZIP Code Tabulation Areas (ZCTA) Use ZCTA as the stand-in for ZIP. API: api.census.gov/data/<year>/acs/acs5 | API/bulk | yearly | Planned |
| State | Census ACS by state (same survey, state geography) | API | yearly | Planned |
| County | Census county list (Gazetteer) PSI Sci collects this (us-county-list) | bulk | yearly | Have now |
| City | Census ACS places (cities and towns) | API | yearly | Planned |
| District | Census county-to-congressional-district relationship files PSI Sci collects this (us-county-districts); ZCTA-to-district file is planned | bulk | after redistricting | Have now |
| ZIP | Census ACS 5-year by ZCTA ZIP code and ZCTA are close but not identical | API/bulk | yearly | Planned |
See these sources as searchable records (rendered live).
See it on PSI Sci now
Variable names
| Variable | Federal | State | County | City | District | ZIP |
|---|---|---|---|---|---|---|
population | fed_population | st_population | cnty_population | cty_population | dist_population | zip_population |
households | fed_households | st_households | cnty_households | cty_households | dist_households | zip_households |
median_income | fed_median_income | st_median_income | cnty_median_income | cty_median_income | dist_median_income | zip_median_income |
age_median | fed_age_median | st_age_median | cnty_age_median | cty_age_median | dist_age_median | zip_age_median |
employment_rate | fed_employment_rate | st_employment_rate | cnty_employment_rate | cty_employment_rate | dist_employment_rate | zip_employment_rate |
zcta | zcta | zcta | zcta | zcta | zcta | zcta |
IDs (like bioguide_id, bill_id, piid, zcta) have no prefix because they already say what they point to.