Representing Ct values above set Cycle baseline? - (Jan/10/2015 )

If the Tissue of interest doesn't show any changes before a set cycle ( say 40) How do I represent this CT value in a table. 

In other words: What is an alternative way to represent this beside writing undetermined?

If your sample is "negative" but you need it for relative ratio calculation, I've heard on some conference that the right way is to determine the detection limit (say it will be Ct - 40) and all the negative samples you will use in calculation as a "detection limit + 1", (i.e. Ct = 41).

But I'm telling this to everyone asking the same question that I haven't been able to find any citation about this (and I'm very eager to see any if someone finds it).