U.S. Energy Information Administration,
Weekly U.S. Retail Gasoline Prices, Gasoline Historical Data. See also
< http://www.eia.doe.gov/oil_gas/petroleum/data_publications/wrgp/mogas_history.html >.
For more information:
http://www.eia.doe.gov/oil_gas/petroleum/data_publications/wrgp/mogas_history.html
Definitions of Gasoline Grades
The classification of gasoline by octane ratings. Each type of gasoline (conventional, oxygenated, and reformulated) is classified by three grades – Regular, Midgrade, and Premium. Note: Gasoline sales are reported by grade in accordance with their classification at the time of sale. In general, automotive octane requirements are lower at high altitudes. Therefore, in some areas of the United States, such as the Rocky Mountain States, the octane ratings for the gasoline grades may be 2 or more octane points lower.
Regular Gasoline: Gasoline having an antiknock index, i.e., octane rating, greater than or equal to 85 and less than 88. Note: Octane requirements may vary by altitude.
Midgrade Gasoline: Gasoline having an antiknock index, i.e., octane rating, greater than or equal to 88 and less than or equal to 90. Note: Octane requirements may vary by altitude.
Premium Gasoline: Gasoline having an antiknock index, i.e., octane rating, greater than 90. Note: Octane requirements may vary by altitude.
Gasoline Price Data Collection Procedures
Every Monday, retail prices for all three grades of gasoline are collected by telephone from a sample of approximately 800 retail gasoline outlets. The prices are published by 5:00 P.M. Monday, except on government holidays, when the data are released on Tuesday (but still represent Monday’s price). The reported price includes all taxes and is the pump price paid by a consumer as of 8:00 A.M. Monday. This price represents the self-serve price except in areas having only full-serve. The price data are used to calculate weighted average price estimates at the city, state, regional and national levels using sales and delivery volume data from other EIA surveys and population estimates from the Bureau of Census.
referenced on dataset section Notes (#2)
