Methods Used by States to Calculate Graduation Rates Under NCLB
Cohort Rate: Percent of students from an entering 9th grade cohort who graduate with a standard diploma within four years. Method can account for transfers and students retained in grade. Student data may be tracked on a statewide or local basis. (10 states)
Leaver Rate: Percent of students leaving high school with a standard high school diploma, expressed as a proportion of all those documented leaving with a diploma or other completion credential or as a dropout. This method is sometimes referred to as a departure- classification index. (33 states)
Completion Ratio: Number of diploma recipients divided by an approximation of the starting 9th grade class. Method cannot fully account for entering cohort membership, net transfer, and grade retention. (2 states)
Dropout Rate: Percent of students enrolled in grades 9 through 12 who drop out during a given school year. High school completion is not measured. (1 state)
Persistence Rate: Percent of students who remain in school from grade 9 through grade 12. Rate is calculated using information on (1) the percent of students not dropping out at specific grade levels or (2) the percent of students estimated to be promoted from grade to grade. This method does not measure high school completion. (3 states)
On-Time Rate: Proportion of all high school graduates in a given year who have received a standard diploma on time. This method compares on-time graduates with those taking longer than four years to earn a diploma. (1 state)
Composite Rate: Proportion of students estimated to remain in high school until grade 12 and receive a diploma. The rate for a given year is calculated by multiplying (1) the rate of persistence between grades 9 and 12 and (2) the percent of completers who receive a diploma rather than another credential. (1 state)
