Columbia, S.C. (WLTX) - Average gas prices in Columbia have fallen 4 cents per gallon in the past week, averaging $2.02 per gallon, according to

This compares to the national average that has fallen 3.7 cents per gallon in the last week to $2.34 per gallon.

"Gasoline prices in much of the country are eroding at a time of year when such a downward fall is anything but par for the course,” said Patrick DeHaan, senior petroleum analyst for "Prices now lay on the fringe of falling under the same point as last year as this year's usual spring rally has been the weakest in recent memory. Factors playing a role: weak demand and strong production, which continue to weigh on OPEC's output cut last November designed to cause prices to rise. The recent drop in crude oil is posing a much more serious threat and OPEC must soon decide how much market share it will sacrifice to keep oil prices higher- clearly the last cut just isn't enough. But while oil remains in focus, U.S. refiners have concluded maintenance season and may soon sputter due to inventories that are bulging with weak gasoline demand the story thus far in 2017, leaving gasoline prices in a weak state- perfect for motorists planning summer road trips."

Including the change in gas prices in Columbia during the past week, prices yesterday were 0.5 cents per gallon higher than the same day one year ago and are 7.1 cents per gallon lower than a month ago.

The lowest price in Columbia right now is the Costco on Piney Grove Road at $1.90.