You can use the following SWQL snippet to retrieve total application availability grouped by application name... so to answer the question: "in aggregate across all nodes where a template may be applied, what is the total application availability?"
Use the following in a custom table widget and place it on a view, or in a custom report.
select
ApplicationName,
avg(PercentAvailability) as AvgAvailability
from
(select
max(ApplicationStatus.TimeStamp) as Month,
Nodes.Caption as NodeName,
Nodes.DetailsUrl as NodesDetailsUrl,
Application.Name as ApplicationName,
Application.DetailsUrl as ApplicationDetailsUrl,
sum(ApplicationStatus.PercentAvailability * ApplicationStatus.RecordCount) / sum(ApplicationStatus.RecordCount) as PercentAvailability
from Orion.APM.ApplicationStatus ApplicationStatus
, Orion.APM.Application Application
, Orion.Nodes Nodes
where ApplicationStatus.TimeStamp >= addminute(minutediff(getdate(), getutcdate()), addmonth(monthdiff(0, getdate()), 0))
and ApplicationStatus.ApplicationID = Application.ApplicationID
and Application.NodeID = Nodes.NodeID
group by Application.ApplicationID, Application.Name, Nodes.Caption, NodesDetailsUrl, ApplicationDetailsUrl
order by Nodes.Caption, Application.Name
) group by ApplicationName
