The Insert Metric option allows you to define a metric within a report based on metrics that are included in that output dataset. When you access the Insert Metric dialog, you must provide a name for the metric and the calculation. There is a Function Wizard button that will provide a list of functions supported in REAS.
Metrics that include spaces in their name must be entered within brackets (e.g., 1 Month HPI Change in the example should be formatted as [1 Month HPI Change] for the application to recognize the metric you wish to use).