Relatively low housing prices and plentiful jobs helped make the Big Island the fastest growing county in Hawai'i last year.

Hawai'i County's population grew 2.9 percent last year, according to U.S. Census Bureau estimates. That was nearly triple the statewide population growth rate of 1 percent between 2004 and last year, according to U.S. Census Bureau estimates.

The Big Island also had the fastest growing population among the state's four counties, with Maui County (1.4 percent) coming in second, followed by Kaua'i (1.3 percent) and Honolulu (0.6 percent), the Census Bureau reported.

Carl Bonham, an economist at the University of Hawai'i-Manoa, said the Big Island's population has been growing faster than Hawai'i for several years.

"We don't know exactly what is causing the Big Island population to grow faster, but it makes sense," Bonham said. "There's more available housing, it's more affordable and there's faster job growth.

"It's cheaper to buy a home on the Big Island than anywhere else (in the state) if you look at the island as a whole."

The county population estimates are used by state and local officials to anticipate demands on county resources such as ports and roads.

Helping buoy the Big Island's economy was a booming year for tourism in 2005. Big Island visitor arrivals rose 16.1 percent last year, which was the biggest gain among all counties, according to the Department of Business, Economic Development and Tourism. That helped the county add 3.3 percent more jobs last year, compared with a statewide job growth rate of 2.8 percent.

The Big Island's faster growth rate has helped push down O'ahu's share of the population to 71 percent of the state's total residents. That's down from 75.5 percent in 1990. Meanwhile, the Big Island's share of the state's population rose to 13.1 percent last year, versus 10.9 percent in 1990.

Nationwide, Flagler County, between Jacksonville and Daytona Beach in Florida, was the fastest-growing county for the second year in a row with a 10.7 percent population increase last year.

Honolulu was the 49th most populous county in the nation, according to the census report.

Reach Sean Hao at shao@honoluluadvertiser.com.