"Combined data from 2002 to 2006 indicated that an annual average of 9.4 percent of persons aged 12 to 20 (3.5 million persons in that age range) met the diagnostic criteria for an alcohol use disorder (dependence or abuse) in the past year."

Source

Pemberton, M. R., Colliver, J. D., Robbins, T. M., & Gfroerer, J. C. (2008). Underage alcohol use: Findings from the 2002-2006 National Surveys on Drug Use and ealth (DHHS Publication No. SMA 08-4333, Analytic Series A-30). Rockville, MD: Substance Abuse and Mental Health Services Administration, Office of Applied Studies, p. 3.
http://drugwarfacts.org/cms/f…