The AFGR method uses an estimate of the number of students who enter ninth grade in one year and then graduate four years later. Because many state data systems have been unable to separate first-time ninth-graders from repeaters, the method estimates the first-time count by averaging a year's ninth grade with eight grade from the year before and tenth grade from the year after. The AFGR reflects the number of graduates in a given year divided by that averaged figure from three years earlier. Thus, the newer rates shown in the graph above come from this set of numbers:
Having shared that data, I'll note that the whole discussion of graduation rates is a troubled and confusing one and will stay that way until our student data system can indeed track a cohort from start of grade 9 to graduation. Using the Infinite Campus data system, we expect that to be possible for the class of 2013.
Until then, the AFGR approximation shows Kentucky much closer to national average two years ago than we were seven years back.
Source note: Data for this post comes from the "Building a Grad Nation" report issued recently by America's Promise, with backup details from National Center for Education Statistics reports on "The Averaged Freshman Graduation Rate for Public High Schools From the Common Core of Data: School Years 2002–03 and 2003-04" and "Public School Graduates and Dropouts From the Common Core of Data: School Year 2007–08 First Look."