It’s been the cheapest summer for gasoline prices in 12 years and consumers have saved nearly $19 billion at the pump, the analytical firm that provides the app GasBuddy said Tuesday morning.

Analysts with the firm said gas prices are on the rise because of rumors that oil-producing countries will reduce their output, but those prices are likely to fall again. GasBuddy’s analysts said supply has outpaced demand for oil for the past couple of years, leading to lower prices.

Labor Day gasoline prices are forecast to be about $2.19 a gallon, GasBuddy said, and the summer average is forecast to be about $2.24 a gallon. Both figures are at their lowest levels since 2004 for the respective time periods.

In Maine, gas prices averaged $2.22 per gallon on Monday, according to GasBuddy’s daily survey of 1,228 gas outlets in the state. That price is one cent higher per gallon than the national average.

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Demand for gasoline typically falls after Labor Day as the busy summer driving season comes to a close. In addition, environmental rules that call for costlier, cleaner-burning gasoline formulas end on Sept. 15 in much of the country, which also helps to keep prices down.

It’s “a double-whammy of downward pressure just in time for autumn,” GasBuddy said in a statement.