The map has dots linking to PDF files that contain the Congested Corridors Statistics—Buffer Index, Planning Time Index, Travel Time Index, Delay per Mile, Congestion Cost. If an individual urban area is listed, it has at least 5 corridors included in the study. If a state is listed, it has corridors from urban areas within that state that contained fewer than 5 corridors in the study.
You can get the numbers—all the numbers—for each of the 328 corridors by downloading the spreadsheet (182KB).
List of Corridors