Platform · Glossary
Census tract.
A statistical subdivision of a county, typically 1,200 to 8,000 residents, designed by the Census Bureau to be relatively homogeneous in population, economic condition, and living conditions. Boundaries are kept stable across decennial cycles to support comparison over time.
Why 3Y uses tracts as the analytical atom
Most market data — incomes, rents, education, employment, housing characteristics — is published at the tract level by the ACS. Tracts are small enough that they generally don’t average across radically different neighborhoods, and large enough that ACS estimates are statistically reliable. Anything coarser, such as county or metro, can blur real differences. Anything finer, such as block group, can lose statistical power for many variables.
This is the unit 3Y uses for tract-level distributions on market pages, for location scoring, and for benchmarking individual properties against their immediate surroundings.
Tract-to-city assignment
3Y assigns a census tract to a city when the tract’s geographic centroid falls within that city’s boundary. This keeps each tract assigned to exactly one city, even when a tract touches or crosses multiple municipal boundaries, and prevents double-counting in city-level distributions.
Tracts are not neighborhoods
A census tract is a statistical construct, not a community boundary. Tract boundaries follow roads, rivers, and political lines convenient for statistical aggregation but don’t necessarily match how residents describe their neighborhood. The 3Y glossary treats “tract” and “neighborhood” as related but distinct: a neighborhood is qualitative and community-defined; a tract is quantitative and Census-defined.
How 3Y resolves a property to its tract
When a user analyzes a property, 3Y resolves the property’s latitude and longitude to the census tract that contains that point. That tract becomes the property’s core geographic anchor for local data, including ACS-based demographics, location scoring inputs, and nearby market context.
For most properties, this is a direct point-in-polygon match: the property coordinate falls inside one census tract boundary, and 3Y uses that tract as the analytical starting point.
For properties near tract, city, county, or flood-zone borders, simple lookup shortcuts can be wrong. 3Y’s spatial system is designed to handle those edge cases by preserving the relevant boundary geometry where needed, then resolving the property against the actual shapes rather than relying only on a broad area label. This helps avoid assigning a property to the wrong tract when it sits close to a boundary.
Once the tract is resolved, 3Y can compare the property with its immediate tract, its broader local area, and the fixed-distance neighborhood views shown in the report. The tract is the starting point, not the whole story: it anchors the analysis, while nearby geography helps explain the surrounding market context.
Tract assignment is analytical, not legal. Census tracts are statistical geographies, not property boundaries, school zones, tax districts, flood determinations, appraisal areas, or neighborhood guarantees. Investors should treat tract-level data as local context for underwriting and due diligence, not as a property-specific certification.