CPI: Massachusetts uses the 100-point Composite Performance Index (CPI) to measure progress towards the goal of narrowing proficiency gaps. The CPI assigns 100, 75, 50, 25, or 0 points to each student participating in MCAS and MCAS Alternate Assessment (MCAS-Alt) tests based on how close they came to scoring Proficient or Advanced. (For example, all students scoring Proficient or Advanced are assigned 100 CPI points; students with very low MCAS scores are assigned 0 CPI points.) The CPI for a student group is calculated by dividing the total number of points by the number of students in the group. The result is a number between 0 and 100.