Gas prices on the decline nationally

For the eighth straight day, gas prices have been on a decline. The national average is now $3.85 per gallon, and some local prices are as low as $3.70.

Experts have cited a number of factors contributing to the comedown, including concerns over Europe and the global recession.

On average, gas is nationally cheaper than it was one year ago, which hasn't happened in more than two years. In D.C., prices have dropped 6 cents in the past week, but are still 5 cents higher than they were this time last year.

Local residents interviewed by ABC7 said they don't expect the fall in prices to continue.

"I'm not optimistic right now. If I see them going down, then maybe," said Robert Engeman, a driver in Arlington, Va.

Experts say it's tough to predict where prices will settle come Memorial Day, and that it will depend on the geopolitical and economic landscapes.

There is one certainty: If gas prices rise, so will airfare.

Economists see high gas prices as among the biggest threats to the economy.