The national average price at the pump for a gallon of diesel fuel fell 2.9 cents this week to $1.194, the Dept. of Energy reported. According to the department’s Energy Information Administration, the last time the national average dropped below $1.20 was on September 6, 1999. While the price has fallen 33.3 cents in the past 11 weeks, which is good news for truckers, the news is not positive for oil refiners and producers. But oil prices will probably weaken by another 20% to $15-$16 per barrel over the next six months, helping drive the world economy out of recession, said Robert Parker, deputy chairman of Credit Suisse Asset Management. Parker said he saw weak demand and swollen inventories depressing oil prices and inflation, despite the best efforts of OPEC cartel members to get prices back up with big supply cuts.The New England region currently has the highest average diesel price, $1.313, while the Gulf Coast has the lowest at $1.142, followed by the Lower Atlantic at $1.143.