The formula is fairly simple. We subtract the students’ most recent prior score from their current score and then divide by the number of days in between the two scores. As a student takes additional assessments, the ROI is updated to reflect, always, the change over time (‘rate’) from one score / assessment to the next.
ROI information can be accessed in the downloadable .csv files that are available once you’ve begun testing a student. The Rate of Improvement is a simple computation based on change in score / # of days between testing sessions. As one is developing instructional goals, however, we encourage you to refer to the national norms, and to set goals based on having students meet or exceed the 50th percentile on those on-grade norms for the various measures. The raw score associated with the 50th percentile varies by measure and season, so using the percentile lines displayed on the Individual Reports can provide a nice referent as well (you can set the ‘target’ goals for these lines through your Admin —> Systems Settings page.
The Rate of Improvement number, or ROI, is available on the Data Export CSV file. To access this feature, go to the Reports section and select Groups. There is a column on the right called Data Export. Select and click on an Export CSV file and the file will download to your desktop. When you open the document, expand the columns. Where applicable, ROI scores will appear in a column to the right of the student’s score.