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40 Truck Drayage Productivity Guide 25% 14% 12% 20% 10% Import Loads Export Loads 15% F re q u e n c y F re q u e n c y 8% 6% 10% 4% 5% 2% 0% 0% 0-10 10-20 20-30 30-40 40-50 50-60 60-70 70-80 80-90 90-100 100-110 110-120 120-130 130+ 0-10 10-20 20-30 30-40 40-50 50-60 60-70 70-80 80-90 90-100 100-110 110-120 120-130 130+ Minutes Minutes (a) Terminal 1. (b) Terminal 2. Figure 5­1. Gate-to-gate turn time distributions. of the transactions (about two standard deviations from the mean) in the expected range and 5% outliers. Turn Time Components Most terminal turn time data are not segmented, so only the total turn time is available for each transaction. One of the case study terminals, however, made segmented data available for import deliveries, as shown in Figure 5­3. Figure 5­3 shows clearly that most of the time at the terminal (once past the queue) is spent in the calendar year (CY). For modern terminals with a high degree of gate automation, the actual time spent at the gates is usually only a few minutes. 20% 18% Example Terminal Turn Time 16% Port-wide Trucker Turn Time 14% 12% 10% 8% 6% 4% 2% 0% 0 10 5 15 5 0 5 0 15 0 22 5 27 0 12 0 13 5 19 5 16 5 24 0 28 5 0 18 0 25 5 21 0 0 -3 -7 -9 -4 -6 19 18 15 22 25 27 12 13 16 21 24 28 30 -1 0- 75 15 30 45 60 5- 0- 0- 5- 5- 0- 0- 0- 5- 5- 0- 5- 5- 90 Figure 5­2. Trucker and terminal turn time comparison.

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Truck Turn Times 41 50 Entry Gate Process Yard Process Exit Gate Process 45 40 Average Truck Turn Time (minutes) 35 30 25 20 15 10 5 0 Jan Feb Mar Apr May Jun Jul Aug Sep Source: Port terminal data, outliers removed. Figure 5­3. Drayage turn time segments. Figure 5­4, from the same source, shows that the variability of the CY process is also far greater than the variability of the gate processes. Accordingly, CY processes are a major focus for identify- ing potential bottlenecks. The relatively small amount of time spent at the gate itself might seem to diminish the impor- tance of gate processing in attempts to reduce turn time. Gate processing times, however, determine outside queue times when trucks arrive faster than they can be served. Each unnecessary minute at the gate is multiplied by the number of trucks in line. 70.00 Entry Gate Process Yard Process Exit Gate Process Avg. Processing Time +/- One Std. Dev. (minutes) 60.00 50.00 40.00 30.00 20.00 10.00 0.00 Jan Feb Mar Apr May Jun Jul Aug Sep -10.00 Source: Port terminal data, outliers removed. Figure 5­4. Terminal turn time variability by segment.