Download the latest release: Compare-MailboxStatistics.ps1
This script compares two sets of mailbox statistics from the same database and highlights mailbox growth that occurred between the two snapshots.
For a growing database, a typical approach would be to start by exporting the statistics for the database:
Get-MailboxStatistics -Database DB1 | Export-CliXML C:\stats-before.xml
After the initial export is obtained, wait until significant growth is observed. That could mean waiting an hour, or a day, depending on the scenario. At that point, compare the stats-before.xml with the live data by using this script as follows:
.\Compare-MailboxStatistics.ps1 -Before (Import-CliXml C:\stats-before.xml) -After (Get-MailboxStatistics -Database DB1)
This makes it easy to see which mailboxes grew the most.