Commented Unassigned: You cannot call a method on a null-valued expression [54277]

I receive this error during the create charts execution (See below)
I have attached the output of the script as well.

Things to note:
* Perfmon blg file is the sample provided
* Running this on a Windows 8.1 environment

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Error:
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Overall progress... Status: Creating charts, PAL 2.7.1 Progress: 76.4705882352941%... Creating charts, PhysicalDisk Read Latency Analysis

An error occurred on...
For ($i=0;$i -le $iValues.GetUpperBound(0);$i++)
At C:\Program Files\PAL\PAL\PAL.ps1:2785 char:15 + For ($i=0;$i -le $iValues.GetUpperBound(0);$i++) + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
You cannot call a method on a null-valued expression.


SCRIPT ARGUMENTS:
Log: C:\Tools\Performance Analysis\PAL\PAL_flatfiles_v2.7.1_x64\PAL\SamplePerfmonLog.blg
ThresholdFile: C:\Tools\Performance Analysis\PAL\PAL_flatfiles_v2.7.1_x64\PAL\SystemOverview.xml
AnalysisInterval: AUTO
IsOutputHtml: $True
IsOutputXml: $False
HtmlOutputFileName: [LogFileName]_PAL_ANALYSIS_[DateTimeStamp].htm
XmlOutputFileName: [LogFileName]_PAL_ANALYSIS_[DateTimeStamp].xml
OutputDir: [My Documents]\PAL Reports
AllCounterStats: $False
NumberOfThreads: 4
IsLowPriority: $True
DisplayReport: True


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Comments: ** Comment from web user: mikecbakker **

Hi,

It seems that the MakeNumeric function is returning a null array

$iValues = MakeNumeric -Values $aValues

Cheers

Mike