Throughout, the goal is to identify from the Charts a subset of materials, not a single material. Finding the best material for a given application involves many considerations, many of them (like availability, appearance and feel) not easily quantifiable. The Charts do not give you the final choice-that requires the use of your judgement and experience. Their power is that guide you quickly and efficiently to a subset of materials worth considering and they make sure that you do not overlook a promising candidate.