Custom Measure(s) can be created by users with a certain permission type. Custom Measures can be built from Campus Labs data Resource, such as Core Data, Beacon, and Engage. The process for creating a Course Evaluation custom measure and is slightly different than those from other Resources, but that is covered in this article, Creating and Publishing a CE Measure.
Custome Measures can have multiple "Metrics" to form a measure's data point. In screenshot A you will notice that I have chosen to create a custom Measure and given it a title of "Enrollment Status (dropped/withdrawn)," which is a distinct count of all students that have a current status of "dropped or withdrawn" and that returns 9 students. But perhaps I want to manipulate that data point for a specific visualization I have in mind. Adding another metric to this custom measure will allow me to do that. Let's transform this single data point of 9 students in a percentage.
In the GIF above you will see that I have added a second Metric (B) which is a distinct count of all students at Demo University. Now that I have that I have used the Expression Builder to divide my two metrics and then multiply them by 100 to receive a percentage of .52%, which means that less than 1% of our student population has the status of either "dropped" or "withdrawn," which is great news for our institution. I can now combine this new measure with dimensions and filters to get even more granular with the data.