VNX xls Tab Header Clarification

Greetings!

When viewing the .xlsx output of a VNX analysis I came across a header category within the tab titled Array Performance.  Exactly what does the CPUDiskUtilization header define?  Is this the SP utilization at that given point in time?  Is it a percentage of utilization that the SPs are at that point in time?  Is it a combination of both SPs utilization?  What does this category define?

Thanks,

Jerry