Percentile Rank

A ranking (1-99) of a student’s performance compared to students in a norm group. It indicates the percentage of students in the norm group who scored at or below the student’s score. For example, a percentile rank of 68 (i.e., a student at the 68th percentile) means that the student performed at least as well as 68% of students in the norm group. (This can also be interpreted to mean that 32% of students in the norm group performed better).

Stanine Score

A Stanine, or “standard nine” score, converts the percentile rank to a 9-point scale. This conversion results in a loss of information, which means that stanine scores are less specific than percentile ranks (e.g., students at the 42nd and 58th percentile both have a stanine score of 5). A stanine score of 1-3 is below average, 4-6 is average, and 7-9 is above average.

Percentile ranks and stanine scores were created using responses from a national sample of students in each grade band and genre.