The average price of a gallon of self-serve regular gasoline in the Inland Empire dropped three-tenths of a cent Thursday to $4.058, one day after falling eight-tenths of a cent.

   The average price in Riverside and San Bernardino counties is eight-tenths of a cent less than one week ago and 2.9 cents lower than one month ago but 27.4 cents more than one year ago, according to figures from the AAA and Oil Price Information Service.

  Following a nine-day streak of increases, the average price has decreased three days and was unchanged twice.

   ``Prices may have risen in the last week in anticipation that the wholesale price would skyrocket as it has been doing in other markets throughout the nation,'' Marie Montgomery of the Automobile Club of Southern California told City News Service. ``When that didn't pan out, local prices have settled down a bit.''