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Supplementary As-Built Cost Analysis 75 Table 17. Resulting sample sizes for each project characteristic. Data Analysis Type Sample Size All projects in dataset 59 All projects used for analysis 51 Soft costs per linear foot 45 Soft cost subcomponents (engineering, management, etc.) 48 Duration from planning/DEIS to construction 13 Duration from preliminary engineering to construction 13 Duration from construction to operations 12 Duration from preliminary engineering to operations 13 Project delay 15 of soft costs for vehicles from other soft costs may not hold consistently across the dataset. (Section C.1 discusses this potential shortfall.) Therefore, several figures below test for the pos- sibility that vehicle soft costs are included in the directed vehicle-specific category and not the overall soft costs category. Establishing the clear use of these related terms (soft costs generally and vehicle soft costs) is an important step in evaluating soft costs and developing a soft cost guidebook. Figure 35 shows the effect of vehicle costs on soft costs as percent of construction. If vehicle soft costs are included mistakenly in overall soft costs, one would expect to see that bigger vehicle purchases cause soft costs as percentage of construction to rise if the underlying guideway construction remains the same. Many of these project cost summaries were collected before there was federal guidance for classifying capital costs into a consistent set of cost cate- gories. Indeed, the data included 59 projects sponsored by numerous different agencies across nearly 35 years of experience. Instead, however, Figure 35 shows that soft costs appeared mostly immune to changing levels of vehicle procurements--the trend was slightly downward in light rail, upward in heavy rail, and zero for both modes, and all correlations were statistically insignif- icant. This is a good indication that vehicle soft costs are not included or reflected within the gen- eral soft costs category (SCC 80). C.6. Soft Costs by Mode and Year Figure 36 expands on the analysis of soft costs by decade in Figure 25 by analyzing average soft costs by mode and decade. The pattern shown in Figure 25 of increasing soft costs over time may in part be the result of no light rail projects from the 1970s being included in the dataset. LIGHT RAIL HEAVY RAIL LIGHT + HEAVY RAIL 100% 100% 100% Soft Costs (% of Construction) Soft Costs (% of Construction) Soft Costs (% of Construction) 90% 90% 90% 80% 80% 80% 70% 70% 70% 60% 60% 60% 50% 50% 50% 40% 40% 40% 30% 30% 30% 20% 20% 20% 10% 2 10% 2 10% 2 R = 0.04 R = 0.00 R = 0.00 0% 0% 0% 0% 10% 20% 30% 0% 10% 20% 30% 0% 10% 20% 30% Vehicle Costs as % of Total Cost Vehicle Costs as % of Total Cost Vehicle Costs as % of Total Cost 2 2 2 R = 0.04 t-Stat = -1.02 R = 0.00 t-Stat = 0.10 R =0 .00 t-Stat: 0.17 Figure 35. Soft costs as a percentage of construction versus vehicle costs as a percentage of total other costs.

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76 Estimating Soft Costs for Major Public Transportation Fixed Guideway Projects LIGHT RAIL HEAVY RAIL LIGHT + HEAVY RAIL 50% 50% 50% Soft Costs (% of Construction) Soft Costs (% of Construction) Soft Costs (% of Construction) 45% 45% 45% 40% 40% 40% 34.2% 34.6% 35.2% 34.5% 33.0% 34.6% 35% 35% 35% 30.9% 27.7% 30% 30% 30% 25.1% 25% 25% 21.4% 25% 21.4% 20% 20% 20% 15% 15% 15% 10% 10% 10% 5% 5% 5% 0% 0% 0% 1970s 1980s 1990s 2000s 1970s 1980s 1990s 2000s 1970s 1980s 1990s 2000s Sample Size: 0 4 5 16 6 10 5 5 6 14 10 21 Figure 36. Soft costs as a percentage of construction by decade and mode. Figure 36 confirms that heavy rail projects are primarily responsible for the pattern of rising soft costs over time. Soft costs for light rail projects have been stable over this same period. However, the higher soft cost percentages are related to light rail projects constructed in the 1980s, possi- bly by agencies developing their initial segments. Figure 37 disaggregates the data in Figure 36 further from decade to actual year of construc- tion. This analysis confirms that the overall correlation for all modes combined is statistically significant, but that heavy rail projects are primarily responsible for the pattern of rising soft costs over time. Although light rail projects show a limited correlation in the increasing relationship, heavy rail projects exhibit a stronger relationship in increasing soft costs over time. Note that midyear of expenditure represents the midpoint of all project expenditures, which is similar to, but not neces- sarily the midpoint of, physical construction. Figure 38, Figure 39, and Figure 40 present the same analysis as the two previous figures but fur- ther disaggregate the soft cost category into several groups of components: PE+FD, FD alone, and construction management and administration. The same overall relationship of rising soft cost per- centage of construction costs holds true, but the relationship is weak. The final design soft costs show a stronger relationship and the same increasing relationship over time for both modes com- bined. The soft costs incurred in construction phases (measured as a percentage of construction LIGHT RAIL HEAVY RAIL LIGHT + HEAVY RAIL 60% 60% 60% Soft Costs (% of Construction) Soft Costs (% of Construction) Soft Costs (% of Construction) 2 2 2 R = 0.02 R = 0.35 R = 0.22 50% 50% 50% 40% 40% 40% 30% 30% 30% 20% 20% 20% 10% 10% 10% 0% 0% 0% 1980 1990 2000 2010 1970 1980 1990 2000 2010 1970 1980 1990 2000 2010 Midyear of Expenditure Midyear of Expenditure Midyear of Expenditure 2 2 2 R = 0.02 t-Stat = 0.71 R = 0.35 t-Stat = 3.628 R = 0.217 t-Stat: 3.69 Figure 37. Soft costs as a percentage of construction versus midyear of expenditure.

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Supplementary As-Built Cost Analysis 77 LIGHT RAIL HEAVY RAIL LIGHT + HEAVY RAIL PE+FD Costs (% of Construction) PE+FD Costs (% of Construction) PE+FD Costs (% of Construction) 45% 45% 45% 40% 2 40% 2 40% 2 R = 0.02 R = 0.00 R = 0.04 35% 35% 35% 30% 30% 30% 25% 25% 25% 20% 20% 20% 15% 15% 15% 10% 10% 10% 5% 5% 5% 0% 0% 0% 1980 1990 2000 2010 1970 1980 1990 2000 2010 1970 1980 1990 2000 2010 Midyear of Expenditure Midyear of Expenditure Midyear of Expenditure 2 2 2 R = 0.02 t-Stat = -0.68 R = 0.00 t-Stat = 0.273 R = 0.04 t-Stat: 1.44 Figure 38. Preliminary engineering and final design costs as a percentage of construction versus midyear of expenditure. LIGHT RAIL HEAVY RAIL LIGHT + HEAVY RAIL Final Design (% of Construction) Final Design (% of Construction) Final Design (% of Construction) 30% 30% 30% 2 2 2 R = 0.09 R = 0.14 R = 0.08 25% 25% 25% 20% 20% 20% 15% 15% 15% 10% 10% 10% 5% 5% 5% 0% 0% 0% 1980 1990 2000 2010 1970 1980 1990 2000 2010 1970 1980 1990 2000 2010 Midyear of Expenditure Midyear of Expenditure Midyear of Expenditure 2 2 2 R = 0.09 t-Stat = -1.42 R = 0.14 t-Stat = 1.917 R = 0.08 t-Stat: 1.93 Figure 39. Final design costs as a percentage of construction versus midyear of expenditure. LIGHT RAIL HEAVY RAIL LIGHT + HEAVY RAIL Management (% of Construction) Management (% of Construction) Management (% of Construction) 35% 35% 35% 30% 30% 30% 25% 25% 25% 20% 20% 20% 15% 15% 15% 10% 10% 10% 5% 2 R = 0.04 5% 2 5% 2 R = 0.32 R = 0.20 0% 0% 0% 1980 1990 2000 2010 1970 1980 1990 2000 2010 1970 1980 1990 2000 2010 Midyear of Expenditure Midyear of Expenditure Midyear of Expenditure 2 2 2 R = 0.04 t-Stat = 0.94 R = 0.32 t-Stat = 3.31 R = 0.20 t-Stat: 3.38 Figure 40. Management and administration costs as a percentage of construction versus midyear of expenditure.