Georgia's high school graduation rate continued to inch upward, hitting 82% last spring for the first time since a new method of counting was implemented nationally eight years ago.

The percentage of students statewide who graduated within four years of starting high school was up slightly from 81.6% the prior year, which in turn was an increase of 1 percentage point from 2017, according to numbers released by the Georgia Department of Education Wednesday morning.

There have been similarly slight increases since 2015. That year, the rate jumped several points to 79%, up from 72.6% in 2014.

It had been climbing steadily since 2011, when the federal government instituted a new, uniform measure for all states. Under the new formula, Georgia's 2011 graduation rate plummeted 13 percentage points, to 67.4% from 80.9. It rose to 69.7% in 2012.

The four-year adjusted cohort graduation rate counts students who transfer to a school but not those who transfer out. Schools must track departing students to ensure they registered elsewhere, and some early increases under the new federal measure may have been due to better bookkeeping.

The new formula revealed that more students were dropping out than had previously been counted and a sizable number were taking five or six years to earn a diploma.

This year in metro Atlanta, only Fulton and Cobb counties were among the big urban districts to beat the state average. Fulton's graduation rate was 87.2% while Cobb's was 87%.

Gwinnett County was more than a percentage point shy of the state average with a rate of 80.9%. Atlanta underperformed at 78%, while DeKalb County was well below at 73.4% with Clayton County down further at 72.7%.

Among these big Atlanta area districts, some schools were up, others were down. The rates fell overall in DeKalb and Gwinnett counties and in the City of Atlanta. They rose in Clayton, Cobb and Fulton counties.

The tiny City Schools of Decatur in DeKalb had the highest rate in metro Atlanta, and among the highest in Georgia, at 95.2%. The even smaller Echols and Webster counties in rural South Georgia had 100% graduation rates.

The statewide rise was shared by all racial and ethnic groups except American Indian/Alaskan students, a tiny fraction of the overall. Hispanics gained the most, with a rise of 1.2 percentage points; whites rose 0.7 points, and blacks gained .02. Students with disabilities showed marked improvement with a 1.8 percentage point rise, and English language learners rose 1.4 points.

This wasn’t the case in districts with downward overall trajectories, such as DeKalb. Whites were up 2.2 points there while blacks were down by nearly as much. Hispanics did even worse, down 3 points, prompting this statement from Superintendent Steve Green: “We are proud that certain student populations have improved,” he said, noting that some high schools had double digit growth. “But this is also evidence that we must double our efforts to maintain an upward trajectory.”

There were other positive spins on what appeared to be bad news. Marietta City Schools in Cobb County, for instance, declined 0.4 percentage points, but the district noted that its 75.7% adjusted rate, which includes student transfers, looks a lot better when counting only those students who entered the city’s only high school as freshmen and stayed all four years. They graduated from Marietta High at a rate of 93%.

“Put simply, when we have the opportunity to nurture and support our high school students, they graduate,” the district said.

The district acknowledged it had “areas” that need to improve, but the example it gave did not involve academics. Rather, it was about the bookkeeping involved in tracking transfer students, a technicality necessary to calculate the school’s four-year cohort.

“State and federal requirements hold Marietta High School accountable for any student who enrolls for at least one day who later withdraws and fails to re-enroll in another school,” the district said. “To better track students who may leave the state or country, we have changed our withdrawal protocols to limit, to the greatest degree possible, the difficulties we face in tracking a student months or years later.”