SQL script to tell how much has been archived in the last 2 weeks for each archive. If you want it for any other time then just edit the 14 to whatever amount of days you want
select ArchiveName,count(*) as 'ItemsArchived' from enterprisevaultdirectory.dbo.root,enterprisevaultdirectory.dbo.archive,archivepoint ,saveset where archiveddate >getdate()-14 and
saveset.archivepointidentity = archivepoint.archivepointidentity and enterprisevaultdirectory.dbo.root.vaultentryid = archivepoint.archivepointid and enterprisevaultdirectory.dbo.root.rootidentity=enterprisevaultdirectory.dbo.archive.rootidentity
group by archivename
order by archivename desc