While Iowa’s unemployment rate declined slightly in December, the number of jobless workers in Marion County increased last month – though the rate is still below the statewide average. That’s according to data recently released by Iowa Workforce Development, which reported an unemployment increase of four-tenths of a percent from November to 6.3 percent last month in Marion County. The 6.3 percent jobless rate in Marion County compares to 6.6 percent statewide, and 10.0 percent for the nation.