New numbers confirm what many Hawai'i residents already suspected: the surge in gasoline prices since late last year has persuaded car and truck owners to cut back on driving.

The amount of gasoline sold in the state between November and March dropped 15 percent compared with a year earlier, according to an Advertiser analysis of state Department of Taxation data.

Moreover, traffic figures show fewer vehicles traveling on H-1 Freeway, while bus pass sales are up.

It appears drivers are cutting back trips, using public transit, car pooling and taking other steps to reduce their gasoline use as they cope with prices that have jumped by more than one-quarter in the past year and passed the psychologically jarring threshold of $4 a gallon in late May.

As of yesterday, the statewide average for a gallon of regular unleaded was $4.366 — the fourth-highest average in the country. It has risen 30 cents in the past month.

The increase in gasoline prices comes as residents face a host of energy-related budget busters.

Hawai'i electricity prices are rising, as is the cost of bringing in cargo from the Mainland and delivering it to stores. Grocery prices are on the rise because of transportation costs and other factors. The University of Hawai'i Economic Research Organization earlier this month boosted its 2008 inflation estimate for the state because of oil-related price gains.

So it's not surprising that people are taking steps to cut back on gasoline purchases or get more out of each tank.

On O'ahu, there seems to be less traffic snaking through Hale'iwa on weekends, as some motorists are putting the brakes on their leisurely weekend jaunts. Tourism is also down from a year earlier, meaning fewer visitors circling the island.

"It's not jam-packed anymore," said Sean Mattox, manager at Surf N Sea, a busy ocean sports shop near the double-arched "rainbow" bridge in Hale'iwa, where traffic backs up on weekends. Mattox said he has noticed slightly less weekend traffic as he rides his bike to work. "In the last six months, gas prices have gone up ridiculously."

ROADS LESS CROWDED

Barney Robinson, operator of two Chevron stations, said it is difficult to remember lowering his gasoline prices at any time in recent months, a period in which prices have breached a record set in 2005 and now reach new heights almost daily.

"I think our last decrease was around September of last year. Since then it's been a steady increase," said Robinson, who noted he has never seen anything like this stretch of price increases in his 30 years in the business.

Robinson also thinks traffic has thinned, noticing there is less traffic when he leaves his station near Honolulu Airport at 5 p.m. and heads for his home in East Honolulu. He said there is less stop-and-go traffic and he is at highway speeds more of the time. As such, he's getting better mileage in his Ford Explorer.

"It seems like there's less people on the roads," Robinson said.

The recent gasoline price increases mean most people are having to carve out a bigger portion of their budgets for gasoline. Compared with a year ago, a driver who travels 8,000 miles a year in a car getting 20 miles a gallon is having to pay $389 more annually for gas. That's on top of the $1,357 the motorist was already paying.

FUEL TAX REVENUE DOWN

The Advertiser analysis of tax department data involved looking at gallons sold by distributors and reported to the state. The period covered November 2007 to March 2008, when prices started marching upward. During that time, the total amount sold fell to 169.4 million gallons from 198.5 million in the same period a year ago. Data weren't available for more recent months when price records were set.

While there are questions about the accuracy of the tax department's numbers on gallons sold — they can swing dramatically month to month because of reporting vagaries — there is no question that state fuel tax revenues are off by double-digit percentages. During the five-month period, the fuel tax take fell to $53.8 million.

That was $7.1 million less than the same period a year earlier and has implications for roadway repairs, because much of the money is transferred to a special fund used by the state Department of Transportation.

Other data also point to a decline in driving. Traffic counters set up by the state Transportation Department on H-1 Freeway at the Halawa Interchange came up with a daily average of 124,903 vehicles traveling in both directions in March.

That was almost 19 percent below counts at the interchange a year earlier.

At TheBus, sales of monthly passes were up 4.3 percent through the first four months of the year. Bus drivers also have commented that traffic seems lighter, said J. Roger Morton, TheBus chief executive officer.

Last week, Morton played golf in 'Ewa Beach with three others. Usually, the foursome meets at the course. This time, they convened in town and car pooled to the course.

Robinson said he is hearing more about people car pooling and notes that people are talking about families taking the higher-mileage car and leaving the SUV at home when they have to go someplace together.

"Bus ridership is up. People are bundling their trips and combining their runs," he said. "People are understanding that we need to be conscious about our energy consumption."