You may have noticed another hike in gas prices around the Valley this week. Some places have gone up more than 30 cents since Christmas.

Gas price hikes are based on a lot of different factors. Deb Stevens-Fitzgerald, professor of economics and statistics at Blue Ridge Community College, says while gas prices are generally determined by supply and demand, our current political situation also contributes the the fluctuating prices.

"Who's going to be elected President this upcoming November? What is that going to do to the United States presence in Iraq? What will that do to stability, and thus production of oil, in the region?," asks Stevens-Fitzgerald.

Along with those factors, consumers must also figure on the manufacturing cost to refine crude oil as well as projected future costs per barrel. With those, it becomes easier to see why crude oil rose to $100 a barrel, which is the highest it's ever been. However, those aren't the only factors that play a role.

Irvin Armentrout, general manager of Rockingham Petroleum, says, there are two other very important things he can see that are affecting the price of oil: the decreased value of the American dollar and the increasing cost of the same amount of crude oil. This means the dollar is worth less compared to other currency and the cost of bringing oil into the country has also gone up.

He says, "When we look at the world market, our dollar will just be less."

He adds that these force costs to go up, but he says there is hope.

"As we look at the market today, initially things have retreated from those levels. Crude close yesterday at little over $96 a barrel and as of now, it's off an additional dollar and a half," says Armentrout.

Stevens-Fitzgerald says, when there is uncertainty in the financial projection for commodities like crude oil, it's not uncommon to see prices fluctuate a lot. As of Friday, most places in the Valley are charging $3.07 per gallon of gas.