Types/Microsoft.PowerShell.Commands.HistoryInfo.types.ps1xml

<?xml version="1.0" encoding="utf-8" ?>
<Types>
  <Type>
    <Name>Microsoft.PowerShell.Commands.HistoryInfo</Name>
    <Members>
      <ScriptProperty>
        <Name>Duration</Name>
        <GetScriptBlock>
                    $this.EndExecutionTime - $this.StartExecutionTime
        </GetScriptBlock>
      </ScriptProperty>
    </Members>
  </Type>
</Types>