Reversing a recent trend in the other direction, the average national retail price of diesel has increased from last week’s average of $1.874 per gallon to $1.912, the U.S. Energy Department announced Sept. 20. The highest prices in the nation continue in California, where the price currently averages $2.152 per gallon, and in the West Coast region, where the price stands at $2.088. Meanwhile, the $1.90 mark was passed in New England, where the price is $1.988; the Central Atlantic, where the price is $1.973 and the Rocky Mountain states, where the price is $1.937; and the East Coast where prices are $1.905. Other prices: $1.829 in the Lower Atlantic states, $1.882 in the Midwest and $1.868 in the Gulf Coast region.