Data to determine the rate of graduation for students in general education are collected by dividing the total number of students graduating by the total number of students graduating plus the total number that dropped out (grades 9 through 12) within the four year cohort for the students.

A similar methodology is used to determine the graduation rate for youth with IEPs. Data regarding the number of students with disabilities who graduate are collected by dividing the total number of students with disabilities ages 17 - 21 graduating by the total number of students with disabilities graduating plus the number of dropouts for the current year and the total number of students with disabilities who dropped out (ages 14 - 16) within the three year cohort for the students.

The method for calculating the graduation rate must be similar to that for general education students. Graduation for gen. ed. is calculated by grade and takes into account the number of students that started as freshman. Thus, the number of students that moved and were not known to be continuing as well as the number of students that dropped out are included in the denominator. Because data for students with disabilities are collected and reported by age, our task was to create a crosswalk between age and grade level in order to form a cohort. So when you try to check the calculations for the graduation rate for students with disabilities, you must go back three years prior and add in the number of students with disabilities who "dropped out" and "who moved and were not known to be continuing" to the denominator.