CmdID / PowerShell / Cmdlets / Get
Get-AvailabilityReportOutage
Use the Get-AvailabilityReportOutage cmdlet to return the daily downtime (if any) for each service entity and its overridden value (if set) to the overall reported availability for the day. Exchange PowerShell reference
From the Exchange PowerShell reference 4 parameters Its page in the reference
Parameters
-IdentityThe Identity parameter specifies the outage.-ReportDateThe ReportDate parameter specifies the date to query for the outage report.-ReportingDatabaseThe ReportingDatabase specifies the name of the database on the reporting server.-ReportingServerThe ReportingServer parameter specifies the name of the reporting database server to connect to.