These numbers do add up. Assuming 240 work days a year (48 weeks), 38 hours is less than 10 minutes a day. The absolute worse, DC at 67 hours a year, is just 17 minutes. For 38 hours a year to equal an extra 40 minutes a day, the commuter would have to go to work only 175 days. Tat's 35 work weeks in the year. If I only had to work 8 months out of the year, I might be ok with an hour commute.

Correction: These numbers DON'T add up.

Reread the entire article. The numbers do add up. It indicates incremental commute time relative to ideal conditions. In other words, it's the extra time wasted due to congestion. Not all variables were shared in the article, so trying to do math from it is futile.

Wayne, the data is from TTI, and the study (in all of its extended detail) is linked in the body of the article. While breaking it down over 240 days worked makes it seem insignificant, look at it another way - the average commuter will give up nearly a "full" working week (38 hours) sitting in traffic each year.