CPU Latency

I am trying to find a definition of Latency (measured in Percent) as found in the CPU chart options in ESXi 5.0.

The "counter description" suggests "the percent of time the VM is unable to run because it is contending for the access to the physical CPU(s)", which sounds very similar to the CPU Ready description that suggests the "percentage of time that the virtual machine was ready, but could not get scheduled to run on the physical CPU".

However, in my observations the CPU Latency and CPU Ready do not move together.

Any help much appreciated.

Thanks, Liam.