is intended to check how old is the oldest event entry in event log.
Event logs can be parsed using Log Parser 2.2 or Windows PowerShell Get-WinEvent cmdlet from local or remote machine.
As the function result is returned PowerShell object which contain data like below LogName : Application LogSpanStatus : Normal ComputerName : Localhost OldestEventTime : 2013-12-06 00:45:13 LogTimeSpan : 430.23:02:55.7739014
Function contributed also to Technet Gallery https://gallery.technet.microsoft.com/PowerShell-Function-to-2ea8205a