Gas price decline: Day 28
Gasoline prices continue to slide, remaining above $4 in only 7 states, AAA finds.
NEW YORK (CNNMoney.com) -- Gas prices continued to slide for the 28th straight day, a daily survey of gas station credit card swipes showed Thursday.
The Daily Fuel Gauge Report from motorist advocacy group AAA and the Oil Price Information Service showed that gas prices fell to a nationwide average of $3.778 a gallon, down from $3.787 a day earlier.
Gas prices have fallen more than 8% since hitting a record high of $4.114 on July 16. However, prices remain more than a dollar higher than where they were a year ago.
The recent slide in gas prices follows a decline in crude futures, which have fallen about 21% since hitting a record high of $147.27 on July 11.
Oil has fallen on signs that high fuel prices are cutting into demand. However, with gas prices falling below the psychologically significant $4 a gallon barrier, driving habits may start to pick up again, according to analysts.
Ethanol: Faced with high gas prices, many Americans have turned to ethanol as their fuel of choice.
The price of E85, an 85% ethanol blend, fell to $3.053 a gallon on average from $3.069, AAA reported.
Ethanol is made primarily from corn and is most commonly available in the Midwest, where much of the nation's corn is grown.
Ethanol burns cleaner than gasoline but has a lower energy content and burns less efficiently in flex fuel vehicles. According to AAA's estimates, a vehicle that burns E85 would pay about $4.017 a gallon to get the same mileage as gas.
Diesel: The average price for diesel fuel, which is used in most trucks and commercial vehicles, fell to $4.47 a gallon from $4.498 the day before, according to AAA.
Because of its use in transporting goods, the price of diesel has risen more than 52% in the last year and helped drive up the prices of products and services.
State prices: AAA, which bases its survey on credit card swipes at up to 100,000 fuel stations around the country, found that gas remains above $4 a gallon in only seven states.
Drivers in Alaska, the state with the highest prices, saw gas prices fall to $4.629 a gallon from $4.642 a day earlier. Drivers in Hawaii, the state with the second-highest prices, saw average prices fall to $4.444 from $4.453. Of the lower 48 states, drivers in Utah paid the most for gas at a state average of $4.087 a gallon.
Missouri had the cheapest gas, with prices falling to $3.528 a gallon from $3.542. Oklahoma prices were the second lowest at $3.559 on average, AAA found.
Drivers in Hawaii, the state with the most expensive diesel, paid an average of $5.40 a gallon for diesel. Diesel was cheapest in Missouri, where prices fell nearly 4 cents to an average of $4.202, according to the AAA survey. 
