When generating an application availability report, the availability of the application may not match the average availability of service monitors that make up the application.
This scenario can occur when the time period selected for the application is before the application was created. For example, if you created the application in April and tried to run an application availability report for March, the overall availability will appear as 100% UNKNOWN whereas the service monitors that make up the application may each have 0% UNKNOWN.
However, the availability of an application is maintained in a fashion similar to that of a service monitor. Uptime Infrastructure Monitor calculates the application status every thirty seconds. If the status has changed since the previous check (e.g. one of the master services has a status of CRIT), the status of the application changes to match the status of the master service and a new entry is stored in the database.