Seeing discrepancy for the same performance metric in windows resources compared to perfmon

Hi, 

I was trying to validate the accuracy of the %processor time (total) captured in Windows Resources in HP LoadRunner Controller and saw that it is quite different from the same metics seen using Performance Monitor. 

Please have a look at the screenshots captured between 4:31:30 and 4:31:40. A spike between 40% and 50% was seen in Performance Monitor but it was around 20% when seen in Windows Resources. 

I am pretty sure this is not a one time glitch. I observed for a long period of time and continue to see the discrepancy. 

Any idea why there is a discrepancy? 

Thanks!
Jason