For everyday travelers, the frustration of traffic is
obvious. Understanding the impact on cities and the
economy, however, is not as straightforward as many
would like. From an economic perspective, congestion’s
main impact is the lost productivity from more time
spent traveling to work rather than working; delaying
(or missing) meetings; foregoing interactions among
individuals or personal activities due to long travel time;
and spending more time to accomplish tasks than would
otherwise be necessary if we could reliably plan for
accomplishing the same things at free-flow speeds