Gasoline prices continued their seasonal downward drift on Dec. 14, falling two and a half cents per gallon compared to a week earlier and down nine cents from a month ago, though they remain up $1.16 compared to a year ago as experts wonder if the falling trend can last amid oil price uncertainty. The national average regular gasoline price fell to $3.323 per gallon on Dec. 14, according to the AAA, down from $3.413 a month ago but still far above the year ago average of $2.164 a gallon. According to the Energy Information Administration (EIA), U.S. regular gasoline retail prices averaged $3.39 per gallon in November, which was the highest monthly average since September 2014. “Gas prices tend to fall a bit this time of year due to the shorter days and less robust demand,” Andrew Gross, AAA spokesperson, said in a statement. “And this trend was assisted by …