The unemployment rate in Warren County rose in May.

According to the Pennsylvania Department of Labor and Industry, the seasonally-adjusted unemployment rate was 4.2 percent in May, an increase of almost half of a point from the 3.8 in April and about the same as the rate from March. The rate is slightly lower than the 4.5 percent a year before.

The county’s rate was the second-lowest in the region — behind only Meadville at 4.0 percent.

Erie’s rate in May was 4.4 percent, Bradford was at 4.6, Oil City rose to 5.3 percent, and Forest County reported 6.0 percent.

The statewide average for May was 4.0 percent, while the national average was 3.7 percent.

In all of the locations listed in the May L&I report, the seasonally-adjusted rate was higher than the rate without the adjustments.

The seasonal adjustments show the county’s labor force down by about 100 workers while the number of unemployed people went up.

The L&I breakdown of employment is not seasonally-adjusted and shows an increase of about 100 workers each in ‘professional and business services’ and ‘leisure and hospitality,’ compared to April. While there are about 200 more people working in the report, there are also some 400 more people in the labor force.

According to the Federal Bureau of Labor Statistics at the U.S. Department of Labor, seasonal adjustment “is a statistical technique that attempts to measure and remove the influences of predictable seasonal patterns to reveal how employment and unemployment changes from month-to-month.”

“These seasonal adjustments make it easier to observe the cyclical, underlying trend and other nonseasonal movements in the series,” making it possible to make month-to-month comparisons.