Data provided by the US Department of Energy's National and Renewable Energy Laboratory https://afdc.energy.gov/data/10962 and the U. S. Department of Transportation Office of Highway Administration https://www.fhwa.dot.gov/policyinformation/statistics/2018/mv1.cfm and https://www.fhwa.dot.gov/policyinformation/statistics/2019/mv1.cfm

From the spreadsheet entitled "Travel by City, County, and Functional Class" INDOT, through its Traffic Statistics Section, collects, summarizes, and interprets information on the traffic traveling on the state's highway system. The data is used to assess transportation needs, system performance and to develop highway planning and programming recommendations. Traffic data also plays a very important role in route planning and in the design of highway projects.