Story highlights The new Lundberg Survey puts the average U.S. gas prices at $3.48 a gallon

That's down nearly 15 cents from two weeks ago and 49 cents since April

The skid follows a decline in crude oil prices, particularly over concerns about Europe

U.S. gasoline prices have dropped by nearly 15 cents a gallon since early June as crude oil continues to fall on global economic fears, the latest Lundberg Survey reported Sunday.

A gallon of regular gasoline dropped to an average of $3.48 per gallon in the continental United States. That's down 14.6 cents from the last biweekly Lundberg Survey, which canvasses about 2,500 filling stations across the Lower 48.

Average gas prices peaked at $3.97 a gallon in early April and were running at $3.63 a year ago, survey publisher Trilby Lundberg said. The skid has continued into the summer driving season, when more Americans hit the road for vacations, she said.

"So far, beyond he benefits to a vacationer, the 49-cent crash is a very, very big number helpful to the entire economy -- especially workers and people seeking work," she said.

Though U.S. demand has gone up, "not dramatically but noticeably," Lundberg said concerns about whether Europe will slump back into recession has sent oil prices plunging in recent weeks -- particularly Europe's benchmark Brent crude, which is down about 25% since April.

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"To have this benefit as an input among other aspects of the economy that aren't doing so good is a positive," she said.

The highest U.S. gas prices in the latest Lundberg Survey, conducted on June 22, were $3.95 a gallon in the San Francisco Bay area. The lowest were in Jackson, Mississippi, at $3.03.

Average prices in some other cities:

Albuquerque, New Mexico: $3.43

Atlanta: $3.32

Birmingham, Alabama: $3.15

Boston: $3.47

Chicago: $3.82

Denver $3.64

Houston: $3.27

Minneapolis: $3.68

Norfolk, Virginia: $3.28

Portland, Oregon: $3.77