Share of TriMet-district residents living within a ¼-mile walk of a frequent-service stop, by population-weighted income fifth. Each fifth holds ~319,000 residents. District-wide, 36.7% of 1.60 M residents are near frequent service.
The gradient is steeply progressive. The poorest fifth of residents are 3.5× more likely to live near frequent service than the richest fifth (60% vs 17%) — because Portland's frequent grid runs through the dense, lower-income inner neighborhoods, while wealthier households cluster in low-density hills and outer suburbs the frequent network doesn't reach. Access by share of people of color tilts the same way but far more gently (32% in the least-diverse fifth up to 44% in the most).
Frequent = TriMet's frequent flag on bus + MAX stops (a static designation, not live headways); access is a ¼-mile straight-line buffer, area-weighted into block groups and clipped to the service district. Source: TriMet Portolan catalog × ACS 2019–2023 block groups.