Sonoma County's unemployment rate fell to 6.6 percent in August as the county continued to show long-term job growth in the health care, hospitality and business service sectors.

The jobless rate declined from 7.1 percent in July, according to data released Friday by the state Employment Development Department.

The county continues to benefit from job growth in several sectors, said Ben Stone, executive director of the Sonoma County Economic Development Board.

For example, he said, health care has been one of the county's faster growing areas.

"I would guess that's also going to continue as Obamacare comes along," Stone said.

Last month the state's unemployment rate increased to 8.9 percent from 8.7 percent in July. The U.S. rate was 7.3 percent.

A decade ago unemployment in the county stood at 5.6 percent. But the rate climbed to 10 percent in the summer of 2009 and hovered near or above that level for two years.

Unemployment has declined significantly from 10 percent in August 2011. It reached its lowest point since the recession at 6.1 percent in May.

In August, the jobless rate fell partly because 800 people dropped out of the labor force, but also because total non-farm employment increased by 1,500 jobs.

The single-biggest increase last month was in local schools, a jump of 800 from July that is deemed typical around the start of the academic year.

When compared to August a year earlier, professional and business services added 800 jobs; hospitality added 500; and educational and health services added 400.

Those three sectors have been the county's leading industries in job growth over time, said Linda Wong, North Bay labor market consultant for the state employment department.

For the leisure and hospitality sector, "August marked the 28th consecutive month of year-over-year increases," Wong said.

Educational and health services, which includes trade schools, social workers and health care professionals, has seen employment growth improve on a year-over-year basis for 38 consecutive months.

And business and professional services jobs have increased from a year earlier for 13 consecutive months.

Stone said the data was a good sign for the county.

"Generally these are three of our flagship sectors in the economy," said.

Since August 2011, leisure and hospitality have added 1,800 jobs. Business administrative and support service jobs have grown by 1,000. And health care companies have hired 900 more workers.

In August, Sonoma County posted the seventh-lowest jobless rate in California. It had ranked eighth in July.

Marin County continues to rank first at with a jobless rate of 5 percent. Napa ranked fourth at 5.8 percent, with Mendocino 12th at 7.3 percent and Lake 47th at 11.6 percent.