The CSU Eligibility Index is a combination of your academic GPA and your highest SAT or ACT score as reported to Cal State Fullerton upon application to the university for general admission. This index is the number used to evaluate applicants in the admission phase and when applying for scholarships. You can calculate your eligibility index by multiplying your grade point average by 800 and adding your total score on the SAT I. Or, if you took the ACT, multiply your grade point average by 200 and add ten times the ACT composite score.