Choke points

The following map highlights in color the stretches of major roads in the New York area that experience congestion.

A couple of improvements can be made:

• The smaller roads should be left out completely rather than dimmed; as noted in the text box, congestion on smaller roads is ignored
• More than two colors will bring out the difference between different roads better; as it stands, it is hard to see that 78 is the most congested.  With more colors, the annotation would be rendered unnecessary

Reference: "The Next Thing in Tolls?", New York Times, June 14, 2006