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Supplementary As-Built Cost Analysis 95 LIGHT + HEAVY RAIL: ALL SOFT COSTS LIGHT + HEAVY RAIL: PE + FD COSTS ONLY 60% 60% PE + FD Costs (% of Construction) Soft Costs (% of Construction) 50% 50% 40% 40% 30% 30% 2 R = 0.06 2 R = 0.00 20% 20% 10% 10% 0% 0% - 2 4 6 8 - 2 4 6 8 Years Elapsed between PE and Construction Years Elapsed between PE and Construction 2 2 Sample Size: 13 R = 0.06 t-Stat = 0.86 Sample Size: 13 R = 0.00 t-Stat = 0.15 Figure 70. Soft costs as a percentage of construction versus years elapsed between preliminary engineering and construction. Figure 72 presents the variance between the project opening date projected during the prelim- inary engineering phase and the actual project opening date and compares this to soft costs as a percentage of construction. Presumably, a deviation from the opening date predicted during engineering phases represents a delay. Note that many projects in this dataset were not delayed at all (zero years), while two actually opened ahead of schedule. Figure 72 shows no strong relation- ship with years of delay and the proportion of soft costs. C.15. Vertical Profile and Soft Cost Measurement Somewhat surprisingly, this soft cost analysis found a relatively weak correlation between vertical profile (and by extension, project complexity) and a variety of soft costs measured as a percentage of construction costs. One possible explanation for this finding is that tunneling and aerial structures increase construction costs so rapidly that soft costs as a share of the project do not change measurably beyond the construction costs and increase the soft cost proportions. LIGHT + HEAVY RAIL: ALL SOFT COSTS LIGHT + HEAVY RAIL: ADMIN COSTS ONLY 50% 50% Management (% of Construction) Soft Costs (% of Construction) 45% 45% 40% 40% 35% 35% 30% 30% 25% 25% 20% 20% 15% 15% 10% 2 10% 2 R = 0.00 R = 0.01 5% 5% 0% 0% - 2 4 6 8 10 - 2 4 6 8 10 Years Elapsed between PE and Operations Years Elapsed between PE and Operations 2 2 Sample Size: 13 R = 0.00 t-Stat = -0.06 Sample Size: 13 R = 0.01 t-Stat = -0.39 Figure 71. Soft costs as a percentage of construction versus years elapsed between preliminary engineering and operations.