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Table 10 Sensitivity analysis for alternative discount rate. Key Assumptions: BRT Speed = 11 mph; No Build Bus Speed = 7 mph BRT Headway = 6 min; No Build Bus Headway = 10 min Pre-Project Mode Share: Auto = 85%; Transit = 15% 7% Discount Rate 3% Discount Rate Daily Person NPV of Net NPV of Net Throughput Benefits (million) C/B Ratio Benefits (million) C/B Ratio 20,000 -$13.7 0.6 -$2.9 0.9 30,000 -$3.3 0.9 $13.2 1.3 40,000 $2.4 1.1 $22.0 1.5 50,000 -$11.6 0.7 $0.3 1.0 Figure 3 shows these results graphically. This There are trade-offs between these variables analysis illustrates the importance of transit travel that affect the estimated net benefits. For instance, time savings to the calculation of BRT net benefits. a higher than average BRT speed may result in a favorable cost/benefit ratio even with relatively lower SECTION 6 CONCLUSIONS passenger throughput, but if transit mode share is low, even a high BRT speed may not result in a favor- This analysis of a hypothetical project shows that able project. Table 12 summarizes the effect of the converting an arterial traffic lane for BRT can result above key input variables that have a strong effect in positive net benefits under certain conditions. The on the cost/benefit ratio, highlighting the conditions analysis also shows that the cost/benefit ratio and under which the ratio is likely to be greater than one. net benefits of this project are highly sensitive to the As may be expected, the best corridors for con- input assumptions. The net benefits expected from verting a lane for BRT are those with relatively high a BRT project are a function of multiple variables, person throughput (at least 40,000 per day) and rel- including the following: atively high pre-project transit mode share (at least Total corridor person throughput, 15%). In corridors with person throughput of 20,000 Pre-project mode share, or less, or with a pre-project transit mode share of BRT travel time savings, and 10% or less, converting a lane to BRT is unlikely to Discount rate. result in positive net benefits. Table 11 Sensitivity analysis for values of BRT speed. Key Assumptions: Discount rate = 7% No Build Bus Speed = 7 mph BRT Headway = 6 min; No Build Bus Headway = 10 min Pre-Project Mode Share: Auto = 85%; Transit = 15% BRT Speed 11 mph BRT Speed 9 mph BRT Speed 13 mph (36% travel time (22% travel time (46% travel time reduction) reduction) reduction) Daily Person Net Benefits Net Benefits Net Benefits Throughput (million) C/B Ratio (million) C/B Ratio (million) C/B Ratio 20,000 -$13.7 0.6 -$22.0 0.4 -$7.5 0.8 30,000 -$3.3 0.9 -$16.4 0.6 $5.3 1.1 40,000 $2.4 1.1 -$15.3 0.6 $14.0 1.4 50,000 -$11.6 0.7 -$50.6 -0.3 $10.3 1.3 14

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BRT speed=11 mph BRT speed=9 mph BRT speed=13 mph 1.6 1.4 1.2 Benefit/Cost Ratio 1.0 0.8 0.6 0.4 0.2 0.0 -0.2 20,000 30,000 40,000 50,000 -0.4 Daily Person Throughput Figure 3 Sensitivity analysis for values of BRT speed. Table 12 Conditions resulting in favorable cost/benefit ratio. Variables Daily Person Throughput Cost/Benefit Ratio >11 BRT Average Speed2 9 mph (22% travel time reduction) 20,000 No 30,000 No 40,000 No 50,000 No 11 mph (36% travel time reduction) 20,000 No 30,000 No 40,000 Yes 50,000 No 13 mph (46% travel time reduction) 20,000 No 30,000 Yes 40,000 Yes 50,000 Yes Auto-Transit Mode Share Pre-Project3 80%20% 20,000 No 30,000 Yes 40,000 Yes 85%15% 20,000 No 30,000 No 40,000 Yes 90%10% 20,000 No 30,000 No 40,000 No BRT Corridor Length4 5 miles 40,000 Yes 8 miles 40,000 Yes 11 miles 40,000 Yes 14 miles 40,000 Yes 17 miles 40,000 Yes Note 1: At 7% discount rate Note 2: Assumes base case transit speed of 7 mph and auto-transit mode share (pre-project) of 85%15% Note 3: Assumes average BRT speed of 11 mph Note 4: Assumes average BRT speed of 11 mph and auto-transit mode share (pre-project) of 85%15% 15