Graduation rates going up About 81.1% of students who were supposed to graduate last spring got their diplomas, which was the highest four-year graduation rate in nine years, according to the Colorado Department of Education. The four-year graduation rate improved by 0.4 percentage points compared to 2018, and 8.7 percentage points since 2010. About 2% of Colorado middle and high school students dropped out during the 2018-2019 school year, down from 2.2% in the previous school year. Graduation rates improved for white, Hispanic and Native Hawaiian and Pacific Islander students.