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Smart Growth

Access to Jobs and Workers Via Transit Technical Documentation and User Guide

In 2013, EPA released version 2.0 of the Smart Location Database to respond to the growing demand for data products and tools that consistently compare the location efficiency of neighborhoods across metropolitan regions and across the United States. Access to Jobs and Workers via Transit is a supplementary data product derived from data used to create the transit accessibility variables in the Smart Location Database.

This data release includes a variety of performance metrics that summarize for each census block group the total number of jobs, population, or workers by wage category that can be reached in a 45-minute transit ride. Coverage is limited to metropolitan regions and counties served by transit agencies that publicly share their service data in a standard format called GTFS.

This User Guide provides a full data dictionary and details the data sources and methodology used to derive these variables.

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