For our purposes, assume that further refinement has occurred and that the major software functions listed in Figure 26.2 are identified. Following the decomposition technique for LOC, an estimation table (Figure 26.2) is developed. A range of LOC estimates is developed for each function. For example , the range of LOC estimates for the 3D geometric analysis function is optimistic, 4600 LOC; most likely,6900 LOC; and pessimistic, 8600 LOC. Applying Equation 26.1, the expected value for the 3D geometric analysis function is 6800 LOC. Other estimates are derived in a similar fashion. By summing vertically in the estimated LOC column, an estimate of 33,200 lines of code is established for the CAD system.