(CNN) -- Gas prices jumped 6 cents over the past two weeks to a national average of $1.92 a gallon, according to a survey published Sunday.

That price is more than a dollar less than the price at the same time last year, said Trilby Lundberg, publisher of the Lundberg Survey. The average cost of a gallon of self-serve regular nationwide a year ago was $2.94.

Prices at the pump have been creeping back up after bottoming out at $1.62 seven weeks ago, Lundberg said. That low was down from record-high prices that reached more than $4 per gallon during the summer.

The recent increase is due in part to gasoline demand, Lundberg told CNN. "Thanks to such low prices, demand is now within shouting distance of its year-ago level," she said.

The latest survey tallied prices Friday at thousands of gas stations nationwide.

The lowest average price was in Cheyenne, Wyoming, where a gallon of self-serve regular cost $1.57. The highest was Anchorage, Alaska at $2.37

Here are the prices in some other cities:

Boston, Massachusetts - $1.89

Washington - $1.93

Atlanta, Georgia - $1.84

Chicago, Illinois - $1.99

Houston, Texas - $1.77

Denver, Colorado - $1.78

Omaha, Nebraska - $1.91

Las Vegas, Nevada - $2.09

Seattle, Washington - $2.11