Seems to work fine here.
Microsoft Windows [Version 6.3.9600]
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C:\Windows>wmic cpu get loadpercentage
LoadPercentage
27
Might also ask over here.
https://social.msdn.microsoft.com/Forums/windowsdesktop/en-US/home?forum=perfmon%2Cscripting&filter=alltypes&sort=lastpostdesc
Regards, Dave Patrick ....
Microsoft Certified Professional
Microsoft MVP [Windows Server] Datacenter Management
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