This report from the Alliance for Excellent Education compares graduation rates reported by the states and the U.S. Department of Education to those reported by independent researchers. It shows that while the average difference between state and independent sources is about 13 percent, the gap ranges from a low of 4 percent to a high of 32 percent. In state and national profiles, the report also considers the costs of high school dropouts and identifies three prerequisites to calculating, reporting, and improving accurate graduation rates: (1) accurate graduation rate calculations common across all states, (2) longitudinal state data systems, and (3) holding high schools accountable for improving student achievement and increasing graduation rates.
Who's Counted? Who's Counting? Understanding High School Graduation Rates
CCRS Center Publication
Alliance for Excellent Education