Interstate Traffic Estimate

Michael Minn 22 May 2018

The Office of Highway Policy Information, FHWA. 2013. "Summary of the extent, usage, and condition of the U.S. Interstate System: By State and Interstate Route Number." Accessed 22 May 2018.

Daily traffic on interstate segments is estimated based on FHWA values aggregated by state, interstate, and rural/urban. Rural/urban determination is based on whether the segment is in a metropolitan statistical area (MSA), which likely overstates the values at the edges of MSAs, and on segments that pass through less-populous MSAs.

Data Source: 2011 Highway Performance Monitoring System (HPMS)

TIGER Shapefiles:
cb_2017_us_state_500k: US States
tl_2017_us_primaryroads: TIGER 2017 Roads shapefile
tl_2017_us_cbsa: 2017 TIGER Core Based Statistical Area shapefile


Linear feature identifier from the "Roads" shapefile

Name of the interstate

Name of the metropolitan statistical area containing the line segment

Urban if in an MSA,
Rural if not in an MSA

STATE: Full name of the state containing the segment

Mean Annual Average Daily Traffic – States report an annual average daily traffic (AADT) for each section of Interstate, which represents the average number of vehicles that use that section of road every day. The number reported in the brief is the unweighted mean of all the AADT’s for each section on each route.