The VMware check with key "vmware.vm.cpu.ready" is described in Zabbix documentation 3.0 as "Percentage of time that the virtual machine was ready, but could not get scheduled to run on the physical CPU."
This is not the case, the return values are actually milliseconds and not percentage.

Derivation:
The key I use is vmware.vm.cpu.ready[{$URL},"UUIDofVM"] to monitor %CPU ready on a VM.
The raw values I receive seem to correlate with the values I see in ESXi console, but the unit of measurment is not the same (see picture_1.png in attachment).

This of course is a huge difference, if I calculate the CPU ready time percentage on the base of actual values from ESX console, I get:
(76 / (20 seconds * 1000)) * 100 = 0.38% CPU Ready
instead of
~76% "%CPU ready" I'd get if I took percent instead of ms as a unit of measurment.

I'd recommend to change the calculation of the item with the formula:
(CPU summation value / (<Chart Interval in Seconds> * 1000)) * 100 = % CPU ready
more info: http://anthonyrhook.com/vsphere-cpu-ready-time/

or state the unit of measurment as milliseconds in the documentation and not as percent.

Thanks and br,
Valentin