Something like this, I would imagine...
SELECT (--Finds count of ALL distinct machine names in the table
SELECT COUNT(DISTINCT MachineName)
FROM yourtable
)
- (--Finds count of distinct machine names updated in last 14 days
SELECT COUNT(DISTINCT MachineName)
FROM yourtable
WHERE TimeUpdated >= GETDATE()-14
)
AS MachinesNotUpdatedLast14
--Jeff Moden
Change is inevitable... Change for the better is not.