Gas price average below $3.70
Only Alaska and Hawaii have an average price above $4 a gallon in the latest AAA survey.
NEW YORK (CNNMoney.com) -- Gasoline prices fell below $3.70 a gallon on average across the nation, with only two states - Alaska and Hawaii - averaging above $4, according to a survey of gas station credit card swipes Friday.
Regular gasoline fell to a national average retail price of $3.692 a gallon at the pump from $3.702 a day earlier, according to the Daily Fuel Gauge Report from motorist group AAA and the Oil Price Information Service.
Prices have fallen for 36 straight days, for a total decline of more than 42 cents since hitting a high of $4.114 a gallon, according to the AAA report.
Alaskan drivers paid an average of $4.552 a gallon, slightly up from $4.549 a day before, while drivers in Hawaii paid about $4.429, according to AAA.
The state with the cheapest gas was Missouri, at an average of $3.452 a gallon, followed by South Carolina at $3.466
Despite gas having fallen more than 10% since mid-July, prices remained more than 91 cents, or nearly 33%, above where they were 12 months ago, according to the survey.
The high price of gas has worried investors in crude oil, gasoline's primary ingredient. Concerned that expensive gasoline had caused drivers to buy less fuel, investors have driven crude prices more than 17% lower since mid-July, pulling retail gas prices with it.
High gas prices have also given consumers pause, as they trade in their low gas mileage trucks and SUVs for more efficient small cars and hybrid vehicles.
Automakers are scrambling to respond by developing vehicles such as the compact Chevy Cruze, and car-based SUVs.
Diesel: The price of diesel fuel, which is used to power most trucks and commercial vehicles, fell to $4.32 from $4.337 a gallon a day before, according to AAA.
Diesel fuel has fallen in price since July, just like gasoline. However, it remains nearly $1.50 higher than a year ago, the survey said.
Diesel's use in shipping and transport has added to the operating costs of many businesses, driving up prices for goods and services as they pass those costs along to customers.
Diesel prices were most expensive in Hawaii, with drivers paying an average of $5.31 a gallon. Diesel was cheapest in Missouri at $4.049 a gallon, according to AAA.
Ethanol: The price of E85, an 85% ethanol blend that can substitute for gas in specially configured "flex-fuel" vehicles, fell to $3.013 a gallon on average from $3.023, AAA reported.
Corn-based ethanol has been getting much attention from drivers due to the high cost of petroleum-based fuels. However E85 fuel is difficult to find outside the corn-producing midwest region, and is not sold in some states.
E85 also generally burns less efficiently than gasoline. According to AAA estimates, drivers of flex-fuel vehicles running E85 would have to pay the equivalent of $3.966 a gallon to get the same mileage as gasoline. 
