Gasoline prices down another 1.6 cents
Decline in AAA survey now at 79 straight days, with price 57% below record set in July.
NEW YORK (CNNMoney.com) -- Gasoline prices continued their steady descent Friday, with the average national price in a motorist group's survey falling for the 79th consecutive day.
Regular unleaded gas fell 1.6 cents to a national average of $1.773 a gallon, according to motorist group AAA.
The price has tumbled nearly 57% from the record high of $4.114 a gallon set July 17. It's down 59 cents in the past month and $1.26 in the past year.
The slowing economy has sent the price of gasoline's main ingredient - crude oil - plummeting on the open market. Crude oil prices have lost more than $100 a barrel since mid-July.
Gas is now selling below $2 a gallon on average in every state except Alaska, at $2.763 a gallon, Hawaii, at $2.613, and New York, at $2.128, according to AAA. The state of Missouri had the cheapest gas at $1.566.
Diesel: The price of diesel fuel, which is used in most trucks and commercial vehicles, has also fallen along with gasoline.
The price fell 1.8 cents Thursday to a national average of $2.704 a gallon, according to the AAA survey.
Diesel prices have also fallen more than $2 a gallon since hitting a record high of $4.845 on July 17.
Ethanol: The price of E85, an 85% ethanol blend made primarily from corn fell 0.1 cent to $1.577 a gallon on average, AAA reported.
E85 can be used in place of regular gas in specially configured "flex-fuel" vehicles, but is not readily available in some states.
The AAA figures, compiled by Oil Price Information Services, are state-wide averages based on credit-card swipes at up to 100,000 service stations across the nation. Individual drivers may see lower fuel prices in different areas of each state. 
