The Associated Press reports that Exxon Mobil CEO Rex Tillerson said he doesn''t think the recent jump in oil prices is hurting the U.S. economy, at least not yet. The head of the world''s largest publicly traded oil company said that in 2008, when oil surged to near $150 per barrel, Americans didn''t change their driving and spending habits until gasoline prices topped $4 per gallon. Average gas prices peaked at $4.11 in July that year. Oil is now about $104 per barrel after rising more than 20 percent over three weeks because of civil unrest in Libya. Tillerson hasn''t seen any reduction in the demand for fuel from consumers or businesses. The national average price for a gallon of gas has increased 40 cents to $3.52 in the same period. Drivers on the West Coast are already paying close to $4, however, and prices are expected to rise through spring and summer.