How to read RRD processor graph

I was looking at my RRD graphs but I don't understand what unit is used for the CPU usage… ???
I am attaching an example. Is the utilization number a percentage? And what about the 'm' suffix?
The pfsense book does not give details on this subject.Thanks!

It's percent, though it's so close to 0 in your case that it's having to scale it down to "milli" (10^3) to have readable numbers without too many 0's after the decimal point.

Makes sense… Thanks!