Paying around $3 a gallon for gas thrills most Hono­­lulu drivers, but it’s less of a joy when you learn the average cost should be $2.49 if our prices had dropped as much as they did on the mainland in the last year.

As of Thursday the average price for regular gas on the mainland was down 38 percent in the past 12 months. The average in Hono­lulu was down only 20 percent, and the statewide average was down only 18 percent.

Mainland drivers are paying an average of $2.04 cents a gallon, which is $1.24 less than what they were paying before global oil prices began to fall. In Hawaii the drop in gas prices has been only 72 cents to a statewide average of $3.30.

The slower decline in Hawaii is due to the lack of competition in the state’s isolated market, said Tom Kloz, chief oil analyst with the Maryland-based Oil Price Information Service.

"People can dance around this issue, (but) there is no question that the competitive landscape for retail is nowhere near the landscape for retail on the North American continent," Klotz said.

Hawaii is the only state where the average gas price is still above $3 per gallon, according to GasBuddy.com, a fuel price monitoring website. Meanwhile the average U.S. price is expected to fall to below $2 per gallon before the end of the month.

Oil fell almost 50 percent last year as the U.S. pumped at the fastest rate in more than three decades and the Organization of Petroleum Exporting Countries resisted calls to cut output. On Thursday benchmark oil was trading around $47 a barrel.

Despite the slower pace at which gas prices are dropping in Hawaii, motorists said they are relieved costs are going down.

"I’m just happy its getting lower," said Dorian Silipa, 30, a Makiki resident, as she filled up her Ram 1500 on Thursday.

"Everyone knows Hawaii’s prices are higher. If you don’t like it, move to the mainland," Silipa said. "Everyone complains, but there is no place like Hawaii. It’s the price you pay."

Kenneth Hokama, 77, a Wai­kiki resident, said he expected Hawaii gas prices to decline slower than the mainland.

"Living in Hawaii — it is part of the lifestyle," Hokama said.

Being on an island has its disadvantages, and Hawaii’s lagging decline in gas prices happens to be one of them, Kloz said.

"It’s an island market with barriers to entry, and it is not looked upon as a big growth market," Kloz said.

Small-business owners or independently owned stations keep charging more as a precaution due to Hawaii’s remote location, said Allison Mac, petroleum analyst for GasBuddy.com.

"Costs are higher just because it is so much harder to get gas to the state. A lot of the stations in Hawaii have to play it safe. There are just a couple of refineries there. If anything happens to one of those refineries, oh my goodness, that could have a huge effect."

Kloz agreed, noting that the limited refineries can lead to the higher prices.

"You’ve got only two refiners, one of which, Chevron, has indicated that they are inclined to look for a buyer and even close that refinery," he said. "It is hard to operate in an area that is not high-growth and regulators have made it clear they are going to wean off of fossil fuel."

Still, at some point Hawaii should catch up to decreases seen on the mainland, Kloz said.

"It may take the opening of more Costcos or something along those lines," he said.

Costco, Sam’s Club and military bases were selling regular for $2.48 in Hono­lulu on Thursday while a Tesoro in Mili­lani had it for $2.79.

As it is in a store owner’s favor to keep prices low, drivers should see prices continue to fall, said Gregg Laskoski, senior petroleum analyst for GasBuddy.com.

"In general terms, retailers want to price their gas as low as possible," he said. "If they are operating a retail store, in all probability they are probably getting more for the food they are selling than they are making on gasoline."