EV journal archiving rates by Exchange mailbox or archive

Ok, this will give you a rate by hour for last 7days

SELECT ex.MbxDisplayName, "Archived Date" = left (convert (varchar, archiveddate,20),14), count(*) as 'Number of Items', sum (Convert(bigint,itemsize))/1024 as 'Size'
FROM Saveset s
Join Archivepoint a on a.ArchivePointIdentity =s.ArchivePointIdentity
Join EnterpriseVaultDirectory.dbo.RetentionCategoryEntry rc on rc.RetentionCategoryIdentity = s.RetentionCategoryIdentity
Join EnterpriseVaultDirectory.dbo.ExchangeMailboxEntry ex on ex.DefaultVaultID = a.ArchivePointID
WHERE ArchivedDate  > dateadd("dd", -7, getdate ())
GROUP BY ArchivePointID,s.ArchivePointIdentity, left(convert (varchar, archiveddate,20),14), ex.MbxDisplayName
ORDER BY "Archived Date" DESC

This will give you a daily archive rate for last 30 days

SELECT ex.MbxDisplayName, "Archived Date" = left (convert (varchar, archiveddate,20),10), count(*) as 'Number of Items', sum (Convert(bigint,itemsize))/1024 as 'Size'
FROM Saveset s
Join Archivepoint a on a.ArchivePointIdentity =s.ArchivePointIdentity
Join EnterpriseVaultDirectory.dbo.RetentionCategoryEntry rc on rc.RetentionCategoryIdentity = s.RetentionCategoryIdentity
Join EnterpriseVaultDirectory.dbo.ExchangeMailboxEntry ex on ex.DefaultVaultID = a.ArchivePointID
WHERE ArchivedDate  > dateadd("dd", -30, getdate ())
GROUP BY ArchivePointID,s.ArchivePointIdentity, left(convert (varchar, archiveddate,20),10), ex.MbxDisplayName
ORDER BY "Archived Date" DESC

You can change the WHERE clause and use a date range in either of these.