US gas prices were the lowest on average in three years in 2013 and would decline further next year, a leading automotive and travel service provider said Tuesday. U.S. drivers paid an average of 3.49 U.S. dollars per gallon for gas in 2013, the lowest level since 2010, according to American Automobile Association (AAA). That was significantly lower than last year's average of 3.60 dollars per gallon, which was the most expensive ever. "It was a relief to see gas prices decline in 2013 following record-breaking pain at the pump in recent years," Jenny Robinson, Manager of Public and Government Affairs for AAA Mid-Atlantic, said in a statement. AAA said 30 states in the U.S. had an annual average price below 3.50 dollars per gallon in 2013, with the cheapest price in the State of South Carolina at 3.24 dollars a gallon. The highest average price was 4.24 dollars per gallon in the State of Hawaii. Gas prices would decline further in 2014 as domestic refineries continued to expand production capacity to take advantage of booming crude oil production, AAA said. "Gas prices should average slightly less in 2014 if everything goes as expected, but most drivers may not even notice because the difference could be relatively small," Robinson added. Today's national average price of gas is 3.32 dollars per gallon, marking the fourth consecutive year of record-breaking prices heading into the New Year, AAA said.