Diesel and gasoline prices keep moving lower while the price of oil has gained a little ground over the past week.

New U.S. Energy Department numbers show the average price of on-highway diesel has fallen 3.3 cents to $3.628 per gallon, just a 0.5 cent higher than a more than three-year low hit three weeks earlier.

Compared to the same time a year ago the average price is 21.6 cents lower.

Prices declined in all parts of the country over the past week, ranging from 1.4 cent in the Central Atlantic states at $3.598 per gallon, to 4.3 cents in the Midwest at $3.743, the highest priced region in the country. Compared to the same time in 2013 prices are between 8.6 cents less in the Midwest to 39.8 cents less in New England at $3.605.

The least expensive part of the country for diesel is the Lower Atlantic states at $3.441, down 2.8 cents from a week ago.

The average cost of regular grade gasoline also fell over the past week, shedding 7.3 cents for an average of $2.821, its lowest level in four-years. Compared to this time in 2013 the price is 47.2 cents less.

Prices are down in all parts of the country over the past week and compared to the same time last year.

Gasoline ranges from a low of $3.593 in the Gulf Coast region to a high of $3.048 in the West Coast region.

Meantime, the price of crude has recovered slightly over the past week despite inching lower on Monday. It closed down 73 cents in New York trading at $75.78 per barrel. That compares to last Tuesday’s opening price of $75.49 per barrel and only a little more than a $1.50 higher than the four-year low hit earlier this month.

OPEC oil cartel ministers are set to meet later in the week to decide on possible crude production cuts in an effort to push prices higher, though some analysts doubt such a move would accomplish this due to falling demand from China and increasing U.S. crude production.