"The findings in this report confirm those from the most recent National Roadside Survey, which in 2007 found that only a small percentage of adult drivers are alcohol-impaired. That survey showed that 2.2% of drivers on the road on Friday afternoon or Friday or Saturday night had a BAC of ?0.08 g/dL (12). Additionally, the findings in this report are consistent with alcohol-impaired driving fatality data. Men accounted for 81% of all alcohol-impaired driving episodes in 2010 and 82% of all alcohol-impaired drivers involved in fatal crashes in 2009 (1). Likewise, men aged 21–34 accounted for 32% of alcohol-impaired driving episodes and 35% of all alcohol-impaired drivers involved in fatal crashes (Tonja Lindsey, National Highway Traffic Safety Administration, personal communication, 2011)."

Source

"Vital Signs: Alcohol-Impaired Driving Among Adults — United States, 2010," Morbidity and Mortality Weekly Report (Atlanta, GA: Centers for Disease Control and Prevention, October 7, 2011) Vol. 60, No. 39, p. 1354.
http://www.cdc.gov/mmwr/pdf/w…