The average price of a gallon of self-serve regular gasoline in the Inland Empire rose to its highest amount since Oct. 2 Friday, increasing 1.5 cents to $3.89.

   The average price in Riverside and San Bernardino counties has risen 24 of the past 25 days and is 7.8 cents more than one week ago and 29.4 cents higher than one month ago, but 40.1 cents less than one year ago, according to figures from the AAA and Oil Price Information Service.

   The average price has risen 29.1 cents over the past 25 days, including 1.3 cents on Thursday.

   ``Industry experts point to civil unrest in Venezuela and South Sudan as reasons for the increases in oil prices in recent days, which does impact gasoline prices,'' said Jeffrey Spring of the Automobile Club of Southern California.

   ``The only silver lining is that gas prices haven't increased as quickly or as much as 2013 or 2012 at this time of the year.''

   The price of crude oil accounts for two-thirds to three-quarters of the price of a gallon of gasoline, according to Tupper Hull of the Western States Petroleum Association, a trade association representing major oil companies in six Western states.