Franklin County is now the fastest-growing county in Ohio. New U.S. Census Bureau estimates show Franklin County grew by nearly one-point-four-percent last year, outpacing Delaware County by a slight margin. Local officials say job growth helped boost the population. The estimates show 56 percent of the people who moved to Ohio between 2010 and 2012 live in Cuyahoga, Franklin and Hamilton counties, home to the state's three largest cities.