WASHINGTON &

For the last seven months, Jennifer Wilcox-Acevedo and her family have lived without a car.

Members of the Bellevue, Wash., family of five walk when they can, take the bus or ride a bike. They've even changed dentists so they can have their teeth taken care of closer to home.

"It's a lifestyle really," said Wilcox-Acevedo, 36, a part-time real estate investor who works out of her home in one of Seattle's largest Eastside suburbs.

Her husband, Humberto Acevedo, a software engineer at Microsoft, rides his bike to work while their three children, ages 6 to 10, ride the bus to school.

The family got the idea after their car, a ten-year-old Ford Explorer, needed some transmission work last fall. Instead of paying thousands to fix the gas-guzzling sport utility vehicle, the family decided to see if they could make do without a car.

Upset by the high price of gas and concerned about the environment, Wilcox-Acevedo called the car-less experiment a simple way to combat global warming.

"I wouldn't say that any of us are crazy environmentalists &

I don't even go to environmental rallies &

we just do what we can," she said in a telephone interview.

Still, she confesses that the idea of going car-less is also a way of protesting the Iraq war and U.S. policy in general in the Middle East. "It's something I can do that's very proactive &

a small piece but it's a start," she said.

The family does not go entirely without burning fossil fuel. On occasion, when the kids have to go to karate or swimming, she will rent a car for a few hours or a half-day, Wilcox-Acevedo said.

The family is an extreme example of a trend being seen throughout the Northwest: Spurred by high gas prices, residents of Washington, Oregon and Idaho are using less gas, bringing per capita consumption to a four-decade low, according to the Sightline Institute, a Seattle-based think tank.

Residents of the three states are using 10 percent less gasoline per person than in 1999 &

the equivalent of each person taking a one-month vacation from driving every year, the report said.

"The Northwest has made important strides on climate action," said Clark Williams-Derry, Sightline's research director and lead author of the annual "Cascadia Scorecard" report, being released today in Seattle.

The report also takes stock of the region's economy, population, health, wildlife and pollution.

"Our cutbacks in gasoline use show that ordinary Northwesterners can make a difference," said Williams-Derry, attributing the shift to continued high prices, concern about the environment and a trend toward greater urbanization throughout the region.

In Idaho &

traditionally, the biggest energy user in the Northwest &

gasoline use is down by 14 percent from 1999 to 2004, the report said. The decline is due in part to the fast-growing Boise area, where population is increasing at a far faster rate than rural Idaho, Williams-Derry said.

The state still had the region's highest use of gasoline and electricity, with an equivalent of 17.4 gallons of gas used per person per week in 2006, compared with 16.2 gallons per person per week in Oregon and 15.3 in Washington.

British Columbia, also part of "Cascadia" as measured by the Sightline group, had the lowest energy usage, with 10.9 gallons of gas per person per week, the report said.

Even with the decrease in gas use, the Northwest still is a big energy consumer, the report said. Because of rising electricity and diesel use, energy use in the region remains about twice as high as energy-efficient nations such as Germany. Residents of British Columbia use a third less energy per person than the Northwest states, the report said.

"The economy has rebounded, and as that happens you start to see an increase in (energy use in) both residential and commercial sectors," Williams-Derry said. "Here in the Northwest electricity is still cheap compared to what you get elsewhere," primarily because of the abundance of government-subsidized hydropower.

The report also warns that sprawl could increase in Oregon, citing voter approval of Measure 37. The 2004 initiative requires governments to pay owners for property value lost from land-use restrictions passed after the property was purchased, or to waive the restrictions.

The report says Measure 37 "threatens to erode Oregon's long-standing leadership in smart growth." In the Portland region alone, more than 2,000 applications have been filed for Measure 37 waivers. Sightline supports an effort to scale back rural development that would be allowed under the property compensation law.