Gas price are plummeting in almost every state. According to petroleum analyst Patrick DeHaan the average price of gas in the U.S. has dropped nearly eight cents since last week, but the story is a little different in Montana.

"Only two states are left out of the decrease looking at average gas prices this week compared to last week," DeHaan said. "Montana is one of the states that fell in the last week. It didn't fall by as much as the national average. Statewide the average price in Montana fell two-and-a-half cents from last week... currently about $2.96 a gallon. That's down from about $2.99 a week ago."

The two states that didn’t see prices fall are Utah and Alaska. DeHaan explains why Montana’s price decrease was smaller than most states.

"The price of oil now $13 a barrel lower than where it started in the month of October, that has opened the door for gas prices to decline. Montana tends to lag changes to average prices, it's a little bit more rural. Price movements don't happen as often, there's a little bit less competition which delays price decreases but it also can delay price increases as well."

Some of the reasons behind the price decrease include concerns about the health of the economy, the allowance of some countries to continue to purchase fuel from a now-sanctioned Iran, and news that Russia and OPEC may increase oil production.