Gas prices down 10% from record
Average gas price slips to $3.681 a gallon, according to daily survey.
NEW YORK (CNNMoney.com) -- Retail gas prices fell overnight Monday, bringing the nationwide average down a total of 43 cents from last month's all-time high, according to a survey of gas station credit card swipes.
The national average price for retail gasoline fell seven-tenths of a cent to $3.681 a gallon from $3.688 a day earlier, according to the Daily Fuel Gauge Report survey from motorist group AAA and the Oil Price Information Service.
Average gas prices have fallen more than 10% since striking a record high of $4.114 a gallon on July 17, according to AAA's data.
Crude oil, the main ingredient in fuel, has fallen more than 17% since July amid concerns about weakening global demand.
The recent slide in prices has brought the average price of gas below $4 a gallon in every state except Hawaii, where gas was selling at $4.401 a gallon, and Alaska, where gas was at $4.583.
The cheapest average gas prices were found in Missouri at $3.438 a gallon.
Gas prices tend to be cheaper in the South, near the Gulf of Mexico, and in states where gas taxes are lower according to Jason Toews, founder of GasBuddy.com.
"A lot of the crude oil comes in on the Gulf Coast," said Toews. Much of the nation's gasoline production is also located in that region.
Gas taxes also vary from region to region. For example, state and local taxes came to about 36 cents in Missouri, as opposed to 63.9 cents in California, according to GasBuddy.com data.
Many drivers have responded to high prices at the pump by driving less and switching to more fuel-efficient vehicles. High gas prices have also raised the profile of alternative fuels like ethanol.
Ethanol: The price of E85, an 85% ethanol blend that can substitute for gas in specially configured "flex-fuel" vehicles, rose to $3.035 a gallon on average from $3.02, AAA reported.
Corn-based ethanol is made from renewable sources and is cheaper than petroleum-based fuels, but it also generally burns less efficiently than gasoline in flex-fuel vehicles. Drivers would have to pay the equivalent of $3.994 a gallon for E85 to get the same mileage as gasoline, according to AAA estimates.
E85 fuel is also difficult to find outside the corn-producing midwest region, and is not sold in some states.
Diesel: Diesel fuel, which is used in most trucks and commercial vehicles, fell to an average price of $4.291 a gallon from $4.305, according to the report.
Like gasoline, diesel fuel prices have fallen since July. However, it remains more than $1.30 higher than a year ago, according to AAA.
High diesel prices have driven up the costs for many businesses, particularly those that rely on shipping and transportation.
Drivers in Hawaii and Alaska paid the most for diesel fuel, at $5.279 and $5.184 per gallon respectively, according to AAA. Diesel was cheapest in Missouri at $4.031 a gallon. 
