Data Dictionary for items shown:

AADT (Annual Average Daily Traffic): The annual average daily traffic count for the segment represented (Total of all vehicles counted in a year divided by 365 days). AADT is calculated annually for all highway segments.
AADT Year: The calendar year for which AADT was calculated.
City: The Federal Information Processing Standard (FIPS) code for the incorporated city or town where the segment is located.
Functional Classification: The classification of the segment of road, as defined by FHWA, which is broken down between rural and urban areas. The functional classification system is based on the grouping of streets and highways into classes, or systems, according to the character of the service they are intended to provide. ( Click for details )
County: Numerical reference of the county where the segment can be found. ( Click for listing )
D: The percentage of the design hour value flowing in the peak direction.
Description: Description of location where traffic count was collected.
Heavy: Heavy trucks; Trucks with 3 or more axles expressed as a percentage of TADT.
K: Design Hour Volume defined as the 30th highest annual hourly traffic volume expressed as a percentage of AADT.
Mile Post: Milepost at midpoint of highway segment represented.
State Route: The State Route number. The lowest state route shown for concurrent routes.
Station: ALDOT identifier for specific count location.
TADT: Commercial vehicles, composed of trucks of all types, expressed as a percent of AADT.
TDHV: Commercial vehicles in the design hour expressed as a percentage of the DHV.