|2006 MSA||2007 MSA||2006 Non-MSA||2007 Non-MSA|
|Omnibus Household Survey||n=528||n=454||n=155||n=151|
|Week prior to interview, not at all congested||27.1||29.0||51.9||66.1|
KEY: CI = confidence interval; MSA = metropolitan statistical area
NOTE: CIs for MSA fi gures are 2.5% and for non-MSA fi gures are 4.8%.
SOURCE: U.S. Department of Transportation, Bureau of Transportation Statistics, Omnibus Household Surveys, November 2006 and 2007.