thanks for the link. Does not make in any clearer either.
In example of variation of 33.42 and 33.26 that results in either a +/- 0.24% variation, or overall delta of 0.48%. Not clear which one would be cited. I still do not understand how that relates to >/<4 Hz.
The table only gives the combined value of Wow&Flutter. It should be possible to give separate values for wow only and flutter only.

