A blank value indicates that either:
A value of zero indicates that there was no attrition in that grade for the year and student group selected.
- The school or district is new in the year selected
- The school or district has no students enrolled in that grade level in the year selected
- The school or district has no grade in the year selected for students from the previous year to advance
- The data is suppressed because the enrollment total is less than 6.