LOS ANGELES (CNS) — The average price of a gallon of self-serve regular gasoline in Los Angeles County rose 5.6 cents Saturday to $5.975, its largest increase since March 19.

The average price has risen for 17 consecutive days, climbing 20.1 cents, including 2.2 cents on Friday. It is 11.1 cents more than one week ago, 15.7 cents higher than one month ago and $1.804 higher than one year ago, according to figures from the AAA and Oil Price Information Service.

The Orange County average price rose seven cents to $5.944, its largest increase since March 10. It has risen 16 of the last 17 days, increasing 22.4 cents, including 3.2 cents Friday. It is 13.2 cents more than one week ago, 17.2 cents higher than one month ago, and $1.814 higher than one year ago.

The national average price rose two cents Saturday to a record $4.452, erasing the previous record set Friday.

“The Phillips 66 Wilmington refinery has been undergoing planned maintenance for nearly a month, keeping upward pressure on local prices, according to Oil Price Information Service,” said Doug Shupe, the Automobile Club of Southern California’s corporate communications manager.

“Another phenomenon that has occurred during this latest price run-up is that premium gasoline has become even more expensive compared to regular grade gasoline. The Auto Club’s Automotive Research Center has found that if your vehicle’s manual just recommends premium fuel and does not require it, the vehicle will operate safely and efficiently with the much less expensive regular gas.”