CHICAGO (CBS) — With crude oil prices down again on Monday, gas prices at the pump likely will continue dropping.

Trilby Lundberg, publisher of Lundberg Survey, said the latest analysis showed gas prices are still going down.

“The average gasoline price at the pump for regular grade is down 8 cents over two weeks, and it’s down 23 cents over the past month. It’s 37 cents under what it was one year ago,” she said.

In the Chicago area, the average price of a gallon of regular unleaded is about $1.66, below the national average by about 7 cents per gallon, according to Normally, Chicago gas prices are among the most expensive in the nation, have been below the national average for more than a week, likely due to an ample supply from Midwest refineries.

Lundberg said predicting where gas prices will go from here is difficult.

“The crude oil price is kind of meandering, and that’s why we don’t know, really, which direction retail gasoline will be going in next,” she said.

In any case, Chicago area gas stations soon will switch to the cleaner more expensive summer blend, so it’s likely prices are near the bottom right now.