See previous months' employment reports.

The job market in the North Bay last month tightened further, with the unemployment rate in half the six counties reaching nearly half of California's new 4-decade low, according to state figures released Friday.

California’s unemployment rate in September slipped to 4.1 percent, the lowest since 1976, according to preliminary estimates by the Employment Development Department. By comparison, state rate a year before was 4.5 percent.

In the North Bay, Marin County had the lowest unemployment rate in September, at 2.2 percent, followed by 2.4 percent in Sonoma County and 2.5 percent in Napa County. Solano County’s unemployment rate was 3.5 percent, with Mendocino County uncharacteristically slightly lower at 3.4 percent.

Lake County had the highest unemployment rate in the North Bay area, at 4.3 percent.

The U.S. unemployment rate lowered to 3.7 percent last month.

Sonoma County

The unemployment rate in Sonoma County in September decreased from a revised estimate of 2.7 percent in August and the year-before rate of 2.9 percent.

Sonoma County added manufacturing jobs from August, along with more positions in financial activities and educational and health services, as the school year resumed. There was a monthly decline in construction jobs and in professional and business services, and trade, transportation and utilities sector employment.

Solano County

The unemployment rate in Solano County went down from a revised 3.9 percent in August and below the 4.2 percent level of a year before.

There was a monthly spike in available government jobs and the educational and health services sector, as well as in construction and manufacturing. There were fewer jobs than in August in leisure and hospitality; trade, transportation and utilities; and financial activities.

Marin County

The unemployment rate in Marin County was down from a revised 2.5 percent in August and below the year-ago estimate of 2.6 percent.

The county added jobs from August to September in educational and health services, leisure and hospitality, and the manufacturing sector. There was a monthly decline in government jobs, the trade, transportation and utilities sector; as well as professional and business services.

Napa County

The unemployment rate in Napa County ebbed from a revised 2.8 percent in August and 3.0 percent the previous September.

The county added jobs month to month in government, professional and business services, and manufacturing. Fewer jobs were available in the leisure and hospitality and in the financial activities sectors than in August.

Mendocino County

Mendocino County’s September joblessness rate eased 0.2 percentage points from the revised August rate of 3.6 percent, which was at the same level as the previous September.

Despite the rate fall in September, Mendocino County slipped from 17th rank to 18th among the 58 counties statewide.

Available jobs in September compared to August were about even. There was a small increase in jobs in manufacturing, educational and health care, but there were fewer jobs in the services industry and government.

Lake County

Unemployment in Lake County was down a half-percentage point from a revised rate of 4.8 percent in August and the previous September.

See previous months' employment reports.