After a five week period of falling diesel prices, the inevitable has hit, prices jumped back up 3.3 cents.  In the past five weeks, the cost of diesel has dropped 19.9 cents according to the U.S Department of Energy.  The U.S national average cost of diesel inched up from $2.928 per u.s gallon to $2.961 a gallon.  For the month ending on June 11, diesel use is up 12% from last year.  As of Monday June 21 2010, crude oil gained 0.8 percent to settle at $77.80 U.S per barrel, this is up from just above $77 U.S per barrel on the New York Mercantile Exchange, according to reports from the Wall Street Journal.