Told you all I could remember about calculating rev rate. I did look it up on Google and found useful infirmation.
I did have trouble working out from you're original post, just what it was you were enquireing about. When I found a way to understand it, I felt rather annoyed that the modern education system ( which I blamed ) set you off in life with such a disadvantage. Young people deserve better than that, was my reaction.
Later posts throw this into some doubt, but I still tend to wonder if that is not some sort of defence mechanism cutting in? - ( I can do it right if I want to.....etc.)
Probably most of the world's troubles - from personal relationships , to wars between countries, stem in reasonable part, from misreading peoples thoughts and intentions, by misunderstanding what they say or write. This can be bad enough with people trying to be as articulate as they can be. ( I wonder have I really got across what I'm trying to )
Please, if you can really do better, do so. If you can't, see what you can teach yourself from observation, and don't allow any crap education system to artifically make you something less than you are.