Hawai'i continues to rank among the top states in the percentage of workers who belong to unions, but membership last year declined for the second straight year, according to the U.S. Bureau of Labor Statistics.

Of the state's 556,000 workers in 2007, 130,000, or 23.4 percent, were union members, the bureau report said. In 2006, 139,000, or 24.7 percent of the workforce, belonged to a union.

Despite two consecutive annual declines, the percentage of union workers in the workforce last year was higher compared with five years earlier. There were 490,000 people employed here in 2002 and 24.5 percent, or 120,000, were part of a union, according to the bureau.

Nationally, the number of union workers rose by 311,000 in 2007 to 15.7 million, the report said. Union members accounted for 12.1 percent of the wage and salary workers, virtually unchanged from the 12.0 percent in 2006.

Hawai'i was one of 20 states above the national average last year, while 30 states had union membership below the average. Hawai'i, which has always been a strong union state, trailing only New York (25.2 percent) and Alaska (23.8 percent) and was one of only four states with membership rates above 20 percent.

Dayton Nakanelua, state director of the 13,000-member United Public Workers union, said membership in his union has been consistent and he doesn't see any major downward trends affecting other unions. He said the lower percentage of union workers could be caused by more new businesses in which the workers aren't organized.

"It will be part of the challenge to all unions to organize workers in those industries," Nakanelua said.

Nora Nomura, deputy executive director of the Hawai'i Government Employees Association, agreed that unions must do more for their membership. The 43,000-member HGEA is the state's largest union.

"Maybe labor as a whole isn't doing a good job of recruiting or getting out there and organizing," Nomura said. "It's something that we should work on, because obviously it helps working conditions and it improves people's quality of life in terms of their pay and benefits."

Reach Curtis Lum at culum@honoluluadvertiser.com.