Tzu-Chun Kuo, "Evaluating Californian Under-Age Drunk Driving Laws: Endogenous Policy Lags", Journal of Applied Econometrics, Vol. 27, No. 7, 2012, pp. 1100-1115. Information on traffic mortality during 1984 and 2002 was obtained from the National Highway Traffic Safety Administration's Fatal Accident Report System (http://www.nhtsa.gov/FARS). The fatality rates were defined per 10,000 persons in the Californian population, including both alcohol and non-alcohol-related crashes. The Californian population can be found at (http://www.cdph.ca.gov/data/statistics/Documents/VSC-2005-0101.pdf). The dependent variable for the evaluation of under-age driving laws is the fatality rate of people under the age of 21 and is held in a variable named "FR_Y". The fatality rate for people between 22 and 24 years old was introduced as the control group and is held in a variable named "FR_O". This study analyzed the policy effects using both quarterly and monthly fatality rates. Therefore, two files are included. The fatality rates for the two groups exhibit substantial seasonal variation. Therefore, a seasonal adjustment has been applied. The seasonal adjustment was done by using EVIEWS 3.1 Version with Census X-11 approach. There are two data files. The monthly data are in tck-data-m.txt, and the quarterly data are in tck-data-q.txt. These are both ASCII files in DOS format. They are zipped in the file tck-data.zip. Unix/Linux users should use "unzip -a". Tzu-Chun Kuo tkuo [AT] veriskhealth.com