How Close for Cycles of Concentration

The credit is pretty vague about defining the "maximum number of cycles without exceeding any filtration levels". Does this need to be exact (to the gallon over a year)? For example, one of my current projects would be limited by Cl- at 6.25 cycles of concentration before reaching the 250 ppm limit. If they're at 6.0 is that good enough? There doesn't seem to be any quantification of "maximum". Within 10%? 1%? Has anybody gotten feedback on this one? Hopefully LEED 4.1 addresses this credit a bit or at least expands the reference guide because it currently leaves a lot undefined.