I was using “could care less” as a statement reflecting apathy. As in: I could care less, but it is not worth the energy required to do so. Also saying that “I couldn’t care less” seems to me to be too varying of a statement to make. How do I know if it is possible to care less than I all ready care, when I already don’t care? Measuring it would, I think, require very tiny and very sophisticated instruments which we currently do possess the technology to create…but your handy chart does come close to fulfilling this requirement.