The unemployment rate for Sonoma County last month was the lowest it's been in six years, dropping to 5 percent, while the North Bay as whole saw a decrease in jobless rates as well, according to preliminary figures released Friday.Sonoma County

Sonoma County's 5 percent rate in May -- the lowest since May 2008 -- was down from a revised 5.3 percent in April and well below the year-ago estimate of 6.5 percent, according to the Employment Development Department.

By comparison, the unadjusted unemployment rate for California was 7.1 percent and 6.1 percent for the nation during the same period.

The county added a total of 8,500 jobs over the year, with significant gains in the following areas: government, which added 4,500 jobs; professional business services, which added 1,500; trade, transportation and utilities, which added 900; manufacturing, which added 700; and construction, which added 500.

Over the month, the tourism sector picked up steam for the busy summer season, with hospitality and tourism adding 800 jobs. Construction added 300, while manufacturing, which includes wine, and government each added 200.

The government sector includes casinos, since they are owned by tribes, meaning Graton Casino and Resort likely played a part in hiring for that sector over the year.Marin County

Marin County continued to post the lowest jobless rate in California at 3.8 percent in May, down from last month's rate of 3.9 percent. Marin is part of the three-county region including San Francisco and San Mateo counties. Industry specifics for Marin are not yet available.Napa County

Napa County posted the fourth lowest unemployment rate in the state at 4.5 percent in May, down from April's rate of 5 percent and below the year-ago rate of 5.7 percent.

Over the year, Napa County added 1,500 jobs, with professional business services adding 600, while manufacturing added 500. Education and health services added 400 and government added 200.

Over the month, leisure and hospitality and professional services each added 200 jobs. Solano County

Solano County's rate dropped in May to 6.6 percent, down from a revised 7 percent in April and down from 8.2 the year prior. 

Yearly job gains totaled 1,500, with trade, transportation and utilities adding 800 and education and health services adding 400. Manufacturing added 300 while professional business services and leisure and hospitality each added 200.

Over the month, Solano County added 1,100 jobs, with hospitality and tourism and professional services each adding 300. Government and construction both added 100 apiece.Mendocino County

Mendocino County's jobless rate in May was 5.9 percent, down from 6.7 percent in April and well below last year's rate of 7.9 percent.

Yearly gains occurred mostly in construction and manufacturing, with each adding 120 jobs, while leisure and hospitality added 100 jobs.Lake County

The unemployment rate in the Lake County was 9 percent in May , down from a revised 10.3 percent in April and below the year-ago estimate of 11.3 percent.