Because of the low fuel taxes, theretail price of gasoline in the US is subject to greater changes (than outside the US) when calculated as a percentage of cost-per-unit. From 1998 to 2004, the price of gasoline was between $1 and $2USD perU.S. gallon.[8] After 2004, the price increased until the average gas price reached a high of $4.11 per U.S. gallon in mid-2008, then dropped approximately $2.60 per U.S. gallon as of September 2009.[8] Recently, the U.S. has experienced an upswing in gas prices of 13.51% from Jan 31st to March 7, 2011.[9]
Most consumer goods have posted prices that excludetax; taxes are added based on a percentage of the purchase price. Because of primitive gasoline pumps in the 1920s, United States gasoline prices are posted with taxes included and the taxes are set on cents per gallon. Taxes are added by federal, state and local governments. (These taxes collect the cost of maintaining the roads.) As of 2009, the federal tax is 18.4¢ per gallon for gasoline and 24.4¢ per gallon for diesel (excludingred diesel).[10] Among states, the highest gasoline tax rates, as of January 2011, are California (47.7¢/gal), New York (47.3¢/gal), Hawaii (45.8¢/gal), and Connecticut (45.2¢/gal).[11] The federal government and many states fail to increase their gasoline taxes over time with inflation. However, some states[Note 1] also charge asales tax as a percentage and vary in amount depending on the cost of the gasoline.
About 9% of all gasoline sold in the US in May 2009 was premium grade, according to theEnergy Information Administration. Some car manufacturers "recommend" premium gasoline but havecomputer-controlled engines that adjust the timing to avoid knocking. So, most cars can burn regular grade gasoline but at a slightly reduced performance.[12] TheAssociated Press said premium gas–which is a higher octane and costs several cents a gallon more than regular unleaded–should be used only if the manufacturer says it is “required”.[13]
To reduce the use of importedoil, the US uses Gasohol (10% ethanol) and E85 (85% ethanol) ethanol/gasoline mixtures.
