ATLANTA (AP) -- Georgia's high school graduation rate has fallen to 67 percent based a new federally mandated calculation.

The state Department of Education released the figure Tuesday morning after months of preparing state lawmakers and other officials for the drop. Under the old calculation, the rate of students receiving diplomas had topped 80 percent, but officials say that number wasn't an accurate picture of Georgia's high school graduates.

Officials say the new formula better accounts for dropouts. The formula divides the number of graduates in a given year by the number of students who enrolled four years earlier.