Every Monday, retail prices for all three grades of gasoline are collected by telephone from a sample of approximately 900 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.