The Housing + Transportation Affordability Index, developed by CNT and its collaborative partners, the Center for Transit Oriented Development (CTOD), is an innovative tool that measures the true affordability of housing. Planners, lenders, and most consumers traditionally measure housing affordability as 30 percent or less of income. The Housing + Transportation Affordability Index, in contrast, takes into account not just the cost of housing, but also the intrinsic value of place, as quantified through transportation costs. Click here to explore how this looks in 52 metropolitan areas in the US.

This work is a project of the Brookings Institution's Urban Markets Initiative and is the most comprehensive study-to-date of the Housing + Transportation Affordability Index. The Index completed for the Brookings Institution has been released in two parts. The first phase was released in January 2006 and specifically examines the variables that inform Housing + Transportation costs in St Paul/ Minneapolis, MN. The key to this report is the finding that the three primary dependent variables in the household transportation model are auto ownership, auto use and transit ridership and that the two primary independent variables are residential density and household income. The Brookings Housing + Transportation Affordability Index Phase I paper can be found here. The second phase of the Brookings project models neighborhood-level data for 52 different metropolitan areas with results available through an interactive mapping website. The Index has received much attention from policy makers for its benefits to planners and TOD advocates and has already served as the basis for various other research projects.