A smaller percentage of Hall County and Gainesville students graduated in four years in 2016 than they did in 2015. Hall County’s overall graduation rate dropped from 83.7 percent to 83.2 percent, and Gainesville’s graduation rate fell from 79.5 percent to 74.4 percent, according to data released Tuesday morning by the Georgia Department of Education. For the fifth straight year, the state’s overall graduation rate increased.