@article{ref1,
title="Unreliable FHWA dataq prompt Institute to stop use and warn others",
journal="IIHS status report",
year="2006",
author="Insurance Institute for Highway Safety, ",
volume="41",
number="5",
pages="6-6",
abstract="Although researchers in the United States have used data collected and reported by the Federal Highway Administration (FHWA) to form the denominators in risk calculations, the FHWA now acknowledges that its data are unreliable in its response to a query by the IIHS. The FHWA collects and publishes vehicle registration and driver licensure data provided by state officials. The IIHS found significant year-to-year fluctuations in the licensure data that aren't explained by population changes, law changes, or any other logical factor. The fluctuations are worst for younger drivers.  For example, the reported number of 16-year-old drivers in Illinois was 79,391 in 1998, 8,159 in 1999, and 88,872 in 2000. Louisiana's reported numbers were 25,675 in 2001, 2 in 2002, and 3 in 2003. Other anomalies were identified.  These discrepancies prompted IIHS researchers to compare FHWA's licensure data with data obtained directly from six states. The results confirm the problems -- data from only two of the six states closely resembled what the FHWA was reporting. In the other states there were numerous and sometimes large differences. FHWA generally undercounted licensed drivers.",
language="",
issn="0018-988X",
doi="",
url="http://dx.doi.org/"
}