Data tracked by the Energy Information Administration (EIA) indicated average retail pump prices for diesel and gasoline maintained their downward slide, falling 1.3 cents and 7.1 cents per gallon this week versus last week, respectively.

The agency noted that the U.S. average retail pump price for diesel dropped to $3.896 per gallon this week, which is 6.9 cents lower per gallon compared to the same week in 2012. Diesel prices fell in all regions of the country but remained above the $4 per gallon mark in New England ($4.045), along the West Coast ($4.045) and in California ($4.128).

EIA noted that the Gulf Coast region experienced the biggest week-over-week drop in diesel prices, with prices falling 1.7 cents to $3.824 per gallon this week; a price that’s also the cheapest in the nation.

The U.S. average retail pump price for gasoline hit $3.561 per gallon this week, which is 16 cents per gallon lower compared to the same week in 2012, the agency said. All regions of the country recorded a drop in gasoline prices with the exception of the Rocky Mountains, where prices increased 6/10ths of a penny to $3.644 this week – a price mark that is 14.4 cents higher compared to the same seven-day stretch last year.

EIA noted that the Gulf Coast is home to the cheapest price for gasoline this week at $3.388 per gallon; a 5.8 cent per gallon drop compared to last week. The Midwest, however, recorded the biggest week-over-week decline in retail gasoline pump prices – an 11.1 cent drop $3.478 per gallon, which is a whopping 31 cents per gallon cheaper compared to the same week in 2012.

The agency noted that fuel prices experienced some significant volatility this year, particularly across the Midwest, with gasoline prices in particular spiking for much of July before falling over the last two weeks or so. In its short term energy outlook published last week, EIA said it expects gasoline prices to keep slowly falling as crude oil prices begin to fall and the summer driving season comes to a close.

Preliminary estimates of gasoline consumption during July 2013 showed relatively strong growth over the same month last year, yet EIA stressed that it expects flat to declining gasoline consumption as improving fuel economy of new vehicles continues to outpace growth in highway travel.

As a result, the agency expects that regular-grade gasoline retail prices – which averaged $3.59 per gallon during the first half of 2013 – should average $3.59 per gallon and $3.33 per gallon during the third and fourth quarters of 2013, respectively.

Led by falling crude oil prices, the projected U.S. average regular gasoline retail price falls from $3.63 per gallon in 2012 to an average $3.52 per gallon in 2013 and $3.37 per gallon in 2014, EIA noted.

Diesel fuel prices, which averaged $3.97 per gallon in 2012, are projected to average $3.92 per gallon in 2013 and $3.76 per gallon in 2014, the agency added.