Are you just adding all the counties’ rates and dividing by 159, or are you taking the population of the counties into account? Fulton County alone has about 1/10th of the state’s population, and the Metro Atlanta area is over half of the state’s population.
You can have high unemployment in the sparsely populated counties, and relatively lower unemployment in the Atlanta metro, and have the per capita unemployment be closer to the low end of the scale.
“Metro Atlanta area is over half of the state’s population.”
I don’t know how Atlanta’s population is distributed, but know that it covers about 4 counties, including Gwinnet, whose UE rate is only 9.5%. Likewise, Savannah is located in Chatham County, with UE of 8.8%. Thus, it is not surprising that the population-weighted figure is much lower than the figure one would get by simply averaging rates across all the counties.