Message Count by Accepted Domain Report

I have found lots of scripts/reports to get emails sent by recipients with counts and such.  I am looking for a script to just get received emails counts to my accepted domains from the internet.  I found the below script from Mike Pfeiffer's(Thanks) Exchange Cookbook.

$Domain=@{}
$report=Get-TransportServer |
Get-MessageTrackingLog -EventId "Send" -ResultSize Unlimited -Start (Get-Date).AddDays(-30) 
Where-Object {$_.ConnectorID -eq '*\Internet'}
if($report) {
   $domains=$report | %{$_.Recipients | %{$_.Split("@")[1]}}
   $domains | %{$domain[$_] = $domain[$_] + 1}
Write-Output $domain > "C:\MessageCountAcceptedDomain.txt"
}

I am trying to modify the above script or if anyone has one.  I need to deprecate some of my smtp domains.  We have a few old ones and would like to clean it up.  The above script gets all email.  I have tried using where-object

#| where-object {$domain -like "*@domain1.com"}
#| where-object {$_.domainname -like "*@domain1.com"}

No luck.  Any ideas?