|Week prior to interview||2006 percent||95% CI||2007 percent||95% CI|
|Very to moderately congested||46.7||4.5% n=683||40.4||4.5% n=605|
|Slight to no congestion||53.3||4.5% n=683||59.6||4.5% n=605|
|Over the last 12 months|
|Better||10.3||2.9% n=680||8.8||2.7% n=607|
|Stayed the same||62.4||4.5% n=680||65.4||4.3% n=607|
|Worse||27.3||3.9% n=680||25.8||3.9% n=607|
KEY: CI = Confidence interval.
SOURCE: U.S. Department of Transportation, Bureau of Transportation Statistics, Omnibus Household Surveys, November 2006 and 2007.