English to Russian Other Education / Pedagogy school district statistics

Goes along with the school district graduation rate in the US school system. I am guessing that it is five-year, because they also count so-called "super seniors", the seniors who had to attend school for additional year in order to graduate. However, it doesn't seem like "adjusted" refers to the 5-year vs. 4-year cohort, since I've seen adjusted 4-year cohort as well.
Here is the sentence: The Graduation Rate is calculated by dividing total Diplomas Earned by the Adjusted 5-Year Cohort.
Thank you so much for your help!