Home
Online Services
Travel
Drivers / Vehicles
Business
Forms
About
Search
A-Z List
Login
Cartography and Traffic Data Home
Data
Iowa Trip Generation
Vehicle-miles traveled
Secondary road miles
Miles of public roads
Volume of traffic on the Primary Road System
AUTOMATIC TRAFFIC RECORDER REPORTS
Rural interstate speed information
Turning Movement diagrams
Geospatial technologies
Digital maps
State maps
Iowa Transportation Map
Iowa Bicycle Map
State map page
State railway maps
Winter road condition map
Bridge embargo map
Vertical clearance map information
City and county maps
Traffic maps
STATEWIDE INTERACTIVE
State
County
City
Interactive Maps
Other maps
CCS/ATR Location map
Federal Functional Classification maps-UrbanListing
Federal Functional Classification maps-CountyListing
Farm-to-Market maps
District highway and transportation maps
Historical maps
Reference post maps
Order Maps
contact information
Links and resources
maps
Vehicle-miles traveled (VMT)
County/system
2020
2019
2018
2017
2016
2015
2014
2013
2012
2011
2010
2009
2008
2007
2006
2005
2004
2003
2002
2001
2000
1999
1998
1997
1996
1995
1994
1993
1992
1991
1990
Classification
2021
2020
2019
2018
2017
2016
2015
2014
2013
2012
2011
2010
2009
2008
2007
2006
2005
2004
2003
2002
2001
Monthly
2021
2020
2019
2018
2017
2016
2015
2014
2013
2012
2011
2010
2009
2008
2007
2006
2005
2004
2003
2002
2001
City
2021
2020
2019
2018
2017
2016
2015
2014
2013
2012
2011
2010
2009
2008
30-year historical VMT by system
Traffic data definitions
Interstate
A full-controlled access divided facility of at least four lanes designated by the Federal Highway Administration as part of the Interstate Highway System
Municipal
Within the limits of any incorporated city or town
Municipal interstate
A full-controlled access divided facility of at least four lanes within the limits of any incorporated city or town
Municipal other primary
All federal and state highways, excluding interstates, within the limits of any incorporated city or town
Municipal streets
Any street within the limits of any incorporated city or town other than interstate or other primary highways
Other primary
All federal and state highways, excluding interstates
Road and city street
Nonprimary and noninterstate routes
Rural
Outside the limits of any incorporated city or town
Rural interstate
Full-controlled access divided facility of at least four lanes outside the limits of any incorporated city or town
Rural other primary
All federal and state highways, excluding interstates, outside the limits of any incorporated city or town
Rural secondary
Any nonfederal or state highway outside the limits of any incorporated city
Vehicle type
A series of motor vehicle types that have been grouped together because of their design similarities
VMT
A measure of total vehicle activity. For a given segment of roadway, the VMT is obtained by multiplying the annual average daily travel (AADT) by the length of the roadway segment. For example, on a 5-mile highway segment traveled by 5,000 vehicles daily (an average obtained over a year), the VMT would be 25,000.
Vehicle type definitions
Cars, pickups, and vans
All two-axle, four-tire vehicles that primarily carry passengers
Motorcycles
All two- or three-wheeled motorized vehicles
Single unit two-axle
All vehicles on a single frame, including trucks, camping and recreational vehicles, motor homes, etc., having two axles and dual-rear wheels
Single unit three-axle
All vehicles on a single frame, including trucks, recreational vehicles, motor homes, etc., having three axles
Single unit four-axle
All trucks on a single frame with four or more axles
Bus
All vehicles manufactured as traditional passenger-carrying buses with two axles and six tires, or three or more axles
Combination four-axle
All vehicles with four or less axles consisting of two units, one of which is a tractor or straight truck power unit
Combination five-axle
All five-axle vehicles consisting of two units, one of which is a tractor or straight power unit
Combination six-axle
All vehicles with six or more axles consisting of two units, one of which is a tractor or straight truck power unit
Double bottom
All vehicles with six or more axles consisting of three units, one of which is a tractor or straight truck power unit