While gasoline wholesale pricing remains favourable due to reduced seasonal demand and continued inventory builds, distillate prices continue to escalate.  Upward pressure on distillate pricing appears to have a variety of supporting factors.  The somewhat improved US economy has resulted in increased commercial traffic with a related increase in demand for diesel.  Increased exports of domestically produced diesel has also played a role.  In addition, due to current US Department of Environment regulations non-ethanol blended highway diesel production attracts government tariffs referred to as Renewable Identification Numbers or RIN's.  Some refiners in an attempt to reduce such costs have substituted furnace oil for offshore diesel export contracts thus pressuring existing heating oil inventories.  WTI crude pricing has been relatively stable over past two weeks averaging $103.06 over the period with market concern over the US budget crisis being the primary influence.