Commuters may have noticed a sharp increase in gas prices in recent months, a trend that is caused by several factors.

The average price of a regular gallon of gas in Illinois was $1.69 on Feb. 28. This is up 19 cents from last month, and 45 cents from a year ago, according to the AAA Web site.

Although the Web site did not offer statistics for DeKalb, it did state that the Rockford average was $1.61. This was up 15 cents from a month ago, and 51 cents from a year ago.

One of the major factors for the increased gas prices is the turbulence in Venezuela, said Ron Planting, manager of information and analysis at the American Petroleum Institute. Workers went from producing three million barrels a day to producing almost none during a recent strike. Although production has resumed in the past three months, the lost oil has not been replenished.

Weather also has been a factor in increased prices. This winter has been colder than normal, raising demand for crude oil, Planting said.

Speculation about war has caused a fluctuation in the price of crude oil as well, said Norma Cooper, manager of community affairs at AAA Chicago Motor Club. Prices often increase because of a fear of interruption in supplies.

A fire in the largest refinery in Indiana most likely helped raise gas prices on a local level as well, Cooper said.

The rises in oil prices don’t only affect motorists. An increase in gas prices has the potential to impact other aspects of the economy. It can raise unemployment and inflation rates, said Carl Campbell, associate professor of economics at NIU.

Increases in unemployment and inflation occurred during the oil price hikes in the late ’70s and early ’80s, and in the early ’90s. Although the increase is fairly recent, and such effects would take time, they are a possible consequence, Campbell said.

An end to the increased gas prices is impossible to predict, Planting said.

“There’s a lot that’s beyond anyone’s control,” Planting said.

Although prices have been uncharacteristically high during the winter months, an increase in price is normal during the shift to summer. This is because of increased demand for gasoline for seasonal vehicles, such as golf carts and for vacations, Cooper said.