Annual average daily traffic (AADT), which represents traffic on a typical day of the year, is used by transportation agencies for reporting requirements, allocating resources, informing decision-making, and supporting various agency functions.
NCHRP Research Report 1124: Guide on Methods for Assigning Counts to Adjustment Factor Groups, from TRB's National Cooperative Highway Research Program, provides information and guidance on the methods for assigning counts to adjustment factor groups used in estimating AADT.
National Academies of Sciences, Engineering, and Medicine. 2024. Guide on Methods for Assigning Counts to Adjustment Factor Groups. Washington, DC: The National Academies Press.
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