WASHINGTON, D.C. --- The average U.S. retail price for regular gasoline has dropped 31 cents per gallon over the past four weeks, from $3.04 per gallon to $2.73 per gallon as of September 4, the Energy Department's Energy Information Administration (EIA) reported. Several states already have average gasoline prices below $2.50 per gallon, and Gasbuddy.com indicates that some retail stations in Ohio are now selling regular gasoline for under $2.20 per gallon. "Based on spot prices of gasoline, it looks like the retail drop will likely continue, at least for the next few weeks, in most regions of the country," the EIA reported in its weekly report. "But how much further they drop, and for how long, will be determined by many factors yet to play out. While the price for West Texas Intermediate crude oil has recently dropped below $68 per barrel, future price developments are highly uncertain." Many of the factors that prompted crude oil prices to reach $70 per barrel (lack of spare production capacity, strong global demand growth, concerns about supply disruptions) remain, the EIA pointed out. Other factors, such as worry over oil infrastructure damage from hurricanes, have been pushed aside, at least temporarily. "While consumers can expect that retail gasoline prices will continue to drop over the near-term, prices will rise again somewhere further down the track if the recent roller coaster pattern of gasoline prices continues," the EIA reported.