LOS ANGELES (CNS) — The average price of a gallon of self-serve regular gasoline in Los Angeles County rose Saturday to its highest amount since Dec. 11, increasing 2.9 cents to $4.641, one day after recording its largest increase since Oct. 1, 4.9 cents.

The average price has risen five of the past six days, increasing 8.1 cents, according to figures from the AAA and Oil Price Information Service. It is 7.9 cents more than one week ago and 11.2 cents higher than one month ago, but 8 cents less than one year ago.

The average price has dropped $1.853 since rising to a record $6.494 on Oct. 5.

The Orange County average price rose to its highest amount since Dec. 7, increasing 3.8 cents to $4.589, one day after recording its largest increase since Sept. 30, 5.2 cents. It has risen five of the past six days, increasing 9.7 cents.

The Orange County average price is 9.4 cents more than one week ago and 13 cents higher than one month ago, but 11.7 cents less than one year ago. It has dropped $1.87 since rising to a record $6.459 on Oct. 5.

The main reasons for the rising prices “are higher crude oil prices worldwide, more expensive summer-blend fuel entering the market before the April 1 mandate for it to be in the market and increased demand as parts of the state and nation warm up leading more people to venture out and take road trips,” Doug Shupe, the Automobile Club of Southern California’s corporate communications manager, told City News Service.

“Also, refineries will soon start planned maintenance, which can reduce supply and lead to even more upward pressure on gas prices.”

The national average price fell for the seventh consecutive day following a 17-day streak of increases, dropping nine-tenths of a cent to $3.482. It is 2.8 cents less than one week ago, but 22.2 cents more than one month ago and 5.9 cents higher than one year ago.

The national average price rose 24.3 cents during the 17-day streak of increases. It has dropped $1.534 since rising to a record $5.016 on June 14.