Hawai'i gasoline prices could slide for a fifth consecutive week Monday as declining consumption and more production capacity on the Mainland lead to lower prices.

Drivers could see a decline of about 3 cents a gallon if wholesale market trends continue today, according to Advertiser calculations.

Prices for a gallon of regular under the state's wholesale price cap law have plunged about 78 cents in the past four weeks as more refineries shuttered by hurricanes Katrina and Rita restart and as Americans cut back on driving. Hawai'i's gas cap, the only in the nation, went into effect on Sept. 1 and is based on wholesale prices in New York, the Gulf Coast and Los Angeles.

"I'm delighted to see it dropping but I don't think it's dropping enough," said Kailua resident Bonnie Gutner, 73.

She said she remains concerned about getting the best price for gas and waits in line at Costco Wholesale on weekends to fill up her Acura sedan.

Gutner said she recently returned from a trip to New Jersey, where gasoline was about $2.30 a gallon. People there were complaining because they weren't used to paying that much, she said.

Hawai'i's gasoline prices remain the highest among the states, according to the American Automobile Association. Hawai'i's average price for a gallon of regular-grade gasoline was $2.85 on Sunday night, while it was $2.38 nationally. Both prices are about 19 percent higher than a year earlier.

The state tomorrow will announce the gas cap for next week. This week's cap took effect yesterday and is 4 cents lower than last week.

In spite of the decline in prices over the past month, Kane'ohe resident Richard Han, 62, said he still is curtailing the amount of driving he does in his taxi. Han said he is reluctant to take calls to pick someone up six or seven miles away because the fare may not pay for the fuel he uses.

"Everyone is kind of happy that the gas price is coming down but I'm not because I don't think it's where it should be," Han said.

Nationally, the price of crude oil for December delivery fell to $59.47 a barrel on the New York Mercantile Exchange, the lowest in more than three months.

"The big question is whether this is the bottom or if we will go lower," said Jason Schenker, an economist at Wachovia Corp. in Charlotte.

Crude oil prices could rise this winter as demand for heating oil picks up, analysts said.

Hawai'i's price cap regulates only wholesale prices and allows gas stations to set whatever price they want. The retail prices don't automatically decline with a drop in the cap because some stations need time to sell remaining higher-priced inventory before they take delivery of cheaper product.

The Advertiser's calculation of next week's price cap is based on data from Bloomberg News Service while the state uses figures supplied by the Oil Price Information Service.

Reach Greg Wiles at gwiles@honoluluadvertiser.com.