CHICAGO – Gas prices are experiencing a year-end spike due to road trip travels during the holidays. According to the American Automobile Association, the majority of states saw gas prices increase in the last week, some by as much as a dime. In LaSalle County, gas prices increase by 7 cents, now at $2.56 per gallon. Putnam County is not far behind at $2.57 compared to $2.48 last week. Bureau County saw the biggest increase of 13 cents, now at $2.60 per gallon. AAA Spokesperson Jeanette Casselano, says gas prices are expected to decrease following the holidays.