"Let me quickly say that part of the reason North Carolina gas taxes are high is because the state performs most of the highway functions in North Carolina," Dr. Walden says. "In other states ... counties do a lot of the highway spending, and so obviously because the state of North Carolina is doing most of the highway spending they are going to have to have a higher tax than in many other states.

If you look, Walden adds, "at the gas tax levied on a per gallon basis, we are high. But if you look at gas tax paid by drivers per miles driven you get a different conclusion.

"In fact I looked at this over the last 20 years, and actually the gas tax paid by the average driver per mile driven is 10 percent lower today than it was 10 years ago, and I think this may be the reason why we see, despite high gas taxes per gallon, ... a lot of highway needs.

"It’s because simply people are driving so much more, using the roads more and actually the revenue for the gas tax per mile driven is lower."