Unemployment tumbled to an 18-year low in Sonoma County in April as the county’s labor force contracted for the second consecutive month, the state Employment Development Department reported Friday.

Employers are continuing to create new jobs while fewer people are looking for work, driving the unemployment rate down to 2.5 percent in April, down from 2.8 percent in March and 3.3 percent a year ago.

It is the lowest unemployment seen in Sonoma County since December 1999, when the jobless rate was 2.3 percent.

As the region’s labor force shrinks, employers will need to consider raising wages to attract top talent, said Robert Eyler, an economist at Sonoma State University.

The county economy has created 3,200 jobs over the past year, boosting employment to 214,700, according to EDD figures. But 1,300 people have left the labor force over the past year, primarily since September, the month before wildfires ripped through Sonoma County.

The result: more jobs and fewer unemployed workers to fill them. The EDD reported only 6,600 people were unemployed and actively looking for work in Sonoma County in April, the smallest number since December 1999.

Unemployment across much of the North Bay — including Marin, Napa, Solano and Mendocino counties — hovered at or below 3.8 percent, the statewide jobless rate.

“I think the underlying idea is that this is a regional marketplace, so these counties all read into the figures,” Eyler said. “Looking at one county won’t give you a true sense of (the big picture).”

In Mendocino County, unemployment fell to 3.8 percent in April, down from 4.4 percent in March and 4.8 percent a year ago. The county has added 510 jobs over the past year, boosting employment to 33,340.

In Lake County, unemployment slid to 5.0 percent in April, down from 5.5 percent in March and 5.7 percent a year ago. The county has added 410 jobs over the past year, boosting employment to 17,090.

In Napa County, unemployment dropped to 2.8 percent in April, down from 3.2 percent in March and 3.6 percent a year ago. The county has added 200 jobs over the past year, boosting employment to 77,300.

The North Bay Business Journal contributed to this story.