Microsoft introduced a script to help administrators tracking usage trend of Windows Server 2003 Terminal Server (TS) Per User (PU) client access licenses (CALs), total usage of Windows Server 2008 TS PU CALs (including expired), and usage of Windows Server 2008 TS PU CALs for a list of specified domains. For more detailed information, download the Per User Report Generation script from here. The batch script to execute the Per User Report Generation script periodically for a Windows Server 2003 TS is available here.