The average price has increased 12.8 cents over the past 18 days, including four-tenths of a cent Monday, according to figures from the AAA and Oil Price Information Service. It is 5.7 cents more than one week ago, 17.7 cents higher than one month ago and $1.306 greater than one year ago.
The average price has risen 92.2 cents since the start of the year, mainly because of a run of 59 increases in 60 days totaling 57.9 cents that ended March 21.
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The Orange County average price rose 1.2 cents to $4.116, one day after a 13-day streak of increases totaling 9.9 cents ended when it dropped three-tenths of a cent. It is 5 cents more than one week ago, 16.6 cents higher than one month ago and $1.309 greater than one year ago.
The Orange County average price has risen 90.8 cents since the start of the year, mainly because of a run of 72 increases in 73 days totaling 68.1 cents that ended March 20.
"The same factors that have been pushing up Southern California gas prices continue to be at work -- constrained supply and both actual and anticipated demand increases as we enter the highest demand period for fuel,'' said Marie Montgomery, a public relations specialist with the Automobile Club of Southern California.
The large price increases from one year ago are the result of significant decreases during the early stage of the coronavirus pandemic, when driving and demand dropped substantially because of stay-at-home orders intended to reduce the spread of the virus.
The Los Angeles County average price is 7.1 cents more than it was on May 11, 2019, while the Orange County average price is 6.3 cents more.
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