Highway condition and performance data are derived from the Highway Performance Monitoring System (HPMS), a cooperative data/analytical effort dating from the late-1970's that involves the Federal Highway Administration (FHWA) and State and local governments. The HPMS includes a statistically drawn sample of about 130,000 highway sections. All HPMS data and estimates of future travel demand are provided to the FHWA through State departments of transportation from existing State or local government databases or transportation plans and programs, including those of Metropolitan Planning Organizations (MPOs).

The HPMS data are collected in accordance with the "Highway Performance Monitoring System Field Manual for the Continuing Analytical and Statistical Data Base." This document is designed to create a uniform and consistent database by providing standardized collection, coding, and reporting instructions for the various data items. The FHWA reviews the State-reported HPMS data for completeness, consistency, and adherence to reporting guidelines. Where necessary, and with close State cooperation, data may be adjusted to improve completeness, consistency, and uniformity.

State and local finance data are derived from the financial reports provided by the States to FHWA in accordance with the "Guide to Reporting Highway Statistics." These are the same data used in compiling the annual "Highway Statistics" report. The FHWA adjusts these data to improve completeness, consistency, and uniformity.

National Bridge Inventory

Bridge condition data are obtained from the National Bridge Inventory (NBI), which includes all bridges that are covered by the National Bridge Inspection Standards and are located on a public road. Generally, each bridge is inspected at least once every 2 years, although bridges with higher risks of engineering problems are inspected more frequently, and certain low-risk bridges get less frequent inspections. All bridge information is verified for completeness, consistency and adherence to reporting guidelines.

National Transit Database

Transit data are derived from the National Transit Database (NTD). (This information was formerly known as Section 15 data.) The NTD includes detailed summaries of financial and operating information provided to the Federal Transit Administration (FTA) by the Nation's transit agencies. The NTD program provides information needed for planning public transportation services and investment strategies. Supplementing this information on transit facilities and fleets with information collected directly from transit operators provides a complete picture of the Nation's transit facilities and equipment.

Fatality Analysis Reporting System (FARS)

National Personal Transportation Survey (NPTS)