When configuring a new Metric Definition to track the duration an incident is assigned to a specific group, which type should be selected?

The "Field value duration" metric type is specifically designed to measure the amount of time a particular field on a record holds a specific value. In this scenario, the goal is to track the duration for which the assignmentgroup field on an incident record is set to a certain group. This metric type automates the calculation of this duration, making it the most direct and appropriate choice. It works by creating records in a metric table (metricinstance) that capture the start time, end time, and duration for each period the condition is met.

B. Script calculation: While a script could achieve this, it is unnecessarily complex for a standard requirement that is directly supported by a built-in metric type.
C. State change: This metric type is used to measure the duration between two different values in the state field, not the duration a different field holds a value.
D. Assignment group: This is the name of a field on the incident table, not a type of metric definition.

1. ServiceNow Product Documentation, "Metric definition types." The documentation explicitly describes the "Field value duration" type as the method to "Create a metric that measures the duration that a field has a specific value."

2. ServiceNow Performance Analytics (PA) Advanced Courseware, "Module: Metrics," Section: "Creating Metric Definitions." This section provides examples, including tracking assignment group duration using the "Field value duration" type.