performance data from WMI Preinstalled Performance Classes

I am using following sample code from MSDN to get cooked performance
data from WMI Preinstalled Performance Classes.

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/wmisdk/wmi/accessing_wmi_preinstalled_performance_classes.asp

I am specifically interested in obtaining statistics for
AvgDiskQueueLength counter for
Win32_PerfFormattedData_PerfDisk_PhysicalDisk='0 C:' object.
I do get non-zero values whenever AvgDiskQueueLength goes about 1 so I
know the code works.
But, I am unclear on how to obtain floating point values for
AvgDiskQueueLength counter as it shows up when we fire up perfmon.
Any ideas?

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