There is a strong likelihood that many of us may have used, or at least heard, casual expressions being bandied about relating to new experiences providing a steep Learning Curve, implying that there is a lot that has to be learnt in a short space of time. However, to the Estimator the term ‘Learning Curve’ often refers to something much more specific (and sinister?) than the casual remark implies, relating instead to an observed and repeatable form of general relationship that can be expressed formulaically.