The number of high school graduates increased nationally by 28 percent between 1996-97 and 2008-09, the last year of actual data (table 12). The number of high school graduates is projected to be 2 percent higher in 2021-22 than in 2008-09. Public schools are expected to have an increase in the number of high school graduates and private schools are expected to have a decrease. The numbers of high school graduates are projected to be higher in 2021-22 than in 2008-09 in the South and West and lower in the Northeast and Midwest (table 14).
Factors affecting the projections
The projections of high school graduates are related to projections of 12th-graders and the historical relationship between the number of 12th-graders and the number of high school graduates. The methodology implicitly includes the net effect of factors such as dropouts, transfers to and from public schools, and, at the state level, migration. For more details, see appendixes A.0 and A.2.
About high school graduates
A high school graduate is defined as an individual who has received formal recognition from school authorities, by the granting of a diploma, for completing a prescribed course of study. This definition does not include other high school completers or high school equivalency recipients. Projections of graduates could be affected by changes in policies influencing graduation requirements.
High school graduates of two or more racesIn the 2008-09 school year, five states reported high school graduate counts for graduates of two or more races. These high school graduate counts were proportioned across the other racial/ethnic categories. When more complete sets of data for high school graduates of two or more races are compiled, separate projections for that category will be presented.
For National Center for Education Statistics (NCES) projections of public high school graduates produced over the last 21 years, the mean absolute percentage errors (MAPEs) for lead times of 1, 2, 5, and 10 years out were 1.0, 1.0, 1.5, and 4.3, respectively. For the 1-year-out prediction, this means that one would expect the projection to be within 1.0 percent of the actual value, on average. For NCES projections of private high school graduates produced over the last 10 years, the MAPEs for lead times of 1, 2, 5, and 10 years out were 0.9, 0.9, 5.0, and 1.6, respectively. For more information, see table A-2 in appendix A.