Platform · Glossary
ACS — American Community Survey.
The U.S. Census Bureau's continuous demographic and economic survey, replacing the long-form decennial census. Roughly 3.5 million households respond each year, with results published at multiple geographic resolutions from the national level down to block groups.
What 3Y reads from it
A non-exhaustive list of ACS tables that show up in a 3Y report:
- B19013 — Median household income
- B25064 — Median gross rent (used in rent benchmarks and rent-to-income)
- B25103 — Real estate taxes paid (used to derive property tax rate)
- B25141 — Insurance and utilities (used to derive property insurance rate)
- B15003 — Educational attainment (used in the college-educated share)
- B01001 — Sex by age (used in the renter-age share, ages 21–44)
These are the workhorses behind most of the demographic and economic benchmarks on 3Y market pages and the neighborhood analytics in the report (1-, 3-, and 5-mile radius views).
Vintages
ACS is published as both 1-year and 5-year estimates. 1-year is fresher but only available for areas with 65,000+ residents; 5-year covers all geographies down to block group and is the version 3Y uses for tract-level work.
When ACS is too coarse
Some tract-level metrics in a report would be too sparse to publish if read directly from ACS — the survey's confidence intervals get wide at finer geographies. In those cases, 3Y falls back to a documented chain: tract → county → metro → state → national. The fallback is visible: if you see the same number across the 1-, 3-, and 5-mile views on a report, the data resolution is broader than the radius, and 3Y is keeping the value consistent rather than inventing precision.