Development and Application of Crash Severity Models for Highway Safety: User Guidelines (2023)

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34 Appendix Table A-1 presents the datasets that were used for SPF estimation and validation for each facility in this project. For estimating crash severity models, the team used data from Highway Safety Information System (HSIS) states plus Florida and Connecticut. The data ranges and distributions can be used as a reference for users to compare with their jurisdictions’ data. Note that throughout this appendix, a dash means that the entry is not applicable, N/A means that the variable was not available in that data set, PC = passenger car, HV = heavy vehicle, and MCO = motorcycle or other.

Table A-1. Summary statistics of data used for model estimation and validation. Facilities Estimation Data (5 years) Validation Data (5 years) State Site Count Total Mile State Site Count Total Mile 1. Rural two-lane, two-way roadways 1.1. Undivided two-lane, two-way roadway segments WA 5,271 1,784 CT 7,083 1,080 1.2. Unsignalized three-leg (stop control on minor-road approaches) intersections MN 1,619 - CT 238 - 1.3. Unsignalized four-leg (stop control on minor-road approaches) intersections MN 2,212 - CT 97 - 1.4. Signalized four-leg intersections MN 68 - CT 31 - 2. Rural multilane highways 2.1. Rural four-lane undivided segments CA 176 75.6 CT 76 5.4 2.2. Rural four-lane divided segments CA 1,072 595.5 MN 542 484.8 2.3. Unsignalized three-leg (stop control on minor-road approaches) intersections CA 409 - MN 209 - 2.4. Unsignalized four-leg (stop control on minor-road approaches) intersections CA 275 - MN 269 - 2.5. Signalized four-leg intersections CA 71 - MN 54 - 3. Urban and suburban arterials 3.1. Two-lane undivided arterials OH 3,608 2526 NC 2,605 1688 3.2. Three-lane arterials including a center two-way left-turn lane OH 141 45 NC 74 17 3.3. Four-lane undivided arterials OH 1,663 922.9 NC 935 486.8 3.4. Four-lane divided arterials (i.e., including a raised or depressed median) OH 862 484.8 NC 1,332 550 3.5. Five-lane arterials including a center two-way left-turn lane OH 50 17.3 NC 14 2.36 3.6. Unsignalized three-leg (stop control on minor-road approaches) intersections CT 798 - MN 794 - 3.7. Signalized three-leg intersections CT 498 - MN 67 - 3.8. Unsignalized four-leg (stop control on minor-road approaches) intersections CT 262 - MN 528 - 3.9. Signalized four-leg intersections CT 986 - MN 632 - 4. Freeway segments 4.1. Rural four-lane divided freeway segments CA 1,286 1,187.4 OH 391 431.7 4.2. Rural six-lane divided freeway segments CA 197 109.3 OH 174 200.5 4.3. Rural eight-lane divided freeway segments CA 144 96.3 - - - 4.4. Urban four-lane divided freeway segments CA 1,393 612.6 OH 1,612 776.8 4.5. Urban six-lane divided freeway segments CA 1,191 504.3 OH 781 438.0 4.6. Urban eight-lane divided freeway segments CA 1,519 513.5 OH 245 112.3 4.7. Urban ten-lane divided freeway segments CA 889 253.7 OH 25 11.9

36 Development and Application of Crash Severity Models for Highway Safety: User Guidelines Table A-2 through Table A-26 provide the descriptive statistics based on the variables collected and used for model estimation and validation. There are two types of variables in the tables: continuous and categorical. The continuous variables are summarized by minimum (min.), maximum (max.), mean, and standard deviation (std. dev.) of each variable. Categorical variables are summarized by the proportion of category. Depending on the type of facilities, variables are used differently to be consistent with HSM. For example, for rural two-lane intersections, only the presence of left- or right-turn lanes is considered, while for the urban and suburban intersections, the number of left or right-turn lanes in the intersection is using QIE aggregation are also provided in the same tables. Finally, summary statistics of the observed crash counts for individual severity level by the site (segment or intersection) are also included in the tables. Specifically: Table A-2 through Table A-5 show the descriptive statistics for variables collected for the rural two-lane, two-way road facility types. • Table A-2: rural two-lane, two-way highways • Table A-3: three-leg stop-controlled intersections on rural two-lane, two-way highways • Table A-4: four-leg stop-controlled intersections on rural two-lane, two-way highways • Table A-5: four-leg signalized intersections on rural two-lane, two-way highways Table A-6 through Table A-10 show the univariate count model results of the rural multilane roadway facility types. • Table A-6: rural four-lane undivided highways • Table A-7: rural four-lane divided highways • Table A-8: three-leg stop-controlled intersections on rural multilane highways • Table A-9: four-leg stop-controlled intersections on rural multilane highways • Table A-10: four-leg signalized intersections on rural multilane highways Table A-11 through Table A-19 show the univariate count model results of the urban/suburban arterial facility types. • Table A-11: urban and suburban two-lane undivided arterials • Table A-12: urban and suburban three-lane arterials with a center two-way left-turn lane • Table A-13: urban and suburban four-lane undivided arterials • Table A-14: urban and suburban four-lane divided arterials • Table A-15: urban and suburban five-lane arterials with a center two-way left-turn lane • Table A-16: three-leg stop-controlled intersections on urban and suburban arterials • Table A-17: three-leg signalized intersections on urban and suburban arterials • Table A-18: four-leg stop-controlled intersections on urban and suburban arterials • Table A-19: four-leg signalized intersections on urban and suburban arterials Table A-20 through Table A-26 show the univariate count model results of the freeway facility types. • Table A-20: rural four-lane freeways • Table A-21: rural six-lane freeways • Table A-22: rural eight-lane freeways • Table A-23: urban four-lane freeways • Table A-24: urban six-lane freeways • Table A-25: urban eight-lane freeways • Table A-26: urban ten-lane freeways considered for model estimation. Summary statistics of driver demographics and vehicle types generated

Table A-2. Rural two-lane, two-way highways. Variable Estimation Dataset (WA/5,271 counts/1,783.890 miles) Validation Dataset (CT/7,083 counts/1,080.222 miles) Roadway Variable Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Shoulder Width (ft) 0 22 4.4 2.4 1 17 3.1 2.2 Shoulder Type (Paved) 93.9% N/A Degrees of Curvature 0.00 30.64 1.13 2.20 0.00 30.40 3.39 3.77 Lane Width (<12 ft) 53.6% 14.0% Presence of Light 16.5% 0% AADT 119 26,543 2,991 3,251.4 70 19,200 3,940.5 3,461 Proportion of Male 0.00 1.00 0.66 0.15 0.00 1.00 0.58 0.18 Proportion of Female 0.00 1.00 0.34 0.15 0.00 1.00 0.40 0.17 Proportion of PC 0.00 1.00 0.89 0.12 0.00 1.00 0.92 0.15 Proportion of HV 0.00 0.69 0.07 0.10 0.00 0.45 0.04 0.06 Proportion of MCO 0.00 0.50 0.03 0.05 0.00 0.20 0.02 0.03 Proportion of Young 0.00 1.00 0.14 0.10 0.00 1.00 0.15 0.10 Proportion of Middle 0.00 1.00 0.79 0.13 0.00 1.00 0.75 0.15 Proportion of Senior 0.00 1.00 0.07 0.06 0.00 1.00 0.08 0.08 Speed Limit (mph) N/A 10–25: 7.2% 26–40: 59% 41–55: 33.9% >55: 0% Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 3 0 0.2 0 2 0 0.1 A 0 5 0 0.2 0 1 0 - B 0 7 0.2 0.6 0 5 0.1 0.4 C 0 11 0.2 0.7 0 5 0.1 0.3 PDO 0 46 1.0 2.1 0 15 0.6 1.2

Table A-3. Three-leg stop-controlled intersections on rural two-lane, two-way highways. Variable Estimation Dataset (MN/1,619 counts) Validation Dataset (CT/238 counts) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Presence of left-turn lane 4.0% 2.5% Presence of right-turn lane 37.3% 2.5% AADT 1 70 18,172 3,647.5 3,104.3 200 18,400 4,632.8 3,142.6 AADT 2 50 10,615 657.9 928.3 50 7,700 1,488.4 1,529.1 Presence of Light 22.1% 36.1% Speed Limit (mph) 10–25: 0.4% 26–40: 23.9% 41–55: 75.8% >55: 0% 10–25: 4.6% 26–40: 54.3% 41–55: 41.1% >55: 0% Proportion of Male 0.00 1.00 0.64 0.15 0.00 1.00 0.59 0.15 Proportion of Female 0.00 1.00 0.35 0.15 0.00 0.71 0.40 0.15 Proportion of PC 0.00 1.00 0.84 0.13 0.00 1.00 0.93 0.12 Proportion of HV 0.00 1.00 0.12 0.11 0.00 0.40 0.04 0.05 Proportion of MCO 0.00 0.33 0.03 0.04 0.00 0.12 0.02 0.02 Proportion of Young 0.00 1.00 0.14 0.08 0.00 0.40 0.14 0.07 Proportion of Middle 0.00 1.00 0.76 0.11 0.00 1.00 0.76 0.11 Proportion of Senior 0.00 0.56 0.09 0.07 0.00 0.50 0.08 0.06 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 1 0 - 0 1 0 - A 0 1 0 - 0 2 0.1 0.3 B 0 4 0.1 0.3 0 9 0.7 1.6 C 0 4 0.1 0.4 0 15 0.9 1.9 PDO 0 9 0.2 0.7 0 76 6.1 9.9

Table A-4. Four-leg stop-controlled intersections on rural two-lane, two-way highways. Variable Estimation Dataset (MN/2,212 counts) Validation Dataset (CT/97 counts) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Presence of left-turn lane 3.2% 3.1% Presence of right-turn lane 39.4% 4.1% AADT 1 75 19,066 3,179.7 2,626.7 500 11,800 4,276.3 2,641.6 AADT 2 50 12,031 747 954 150 5,600 1,633.5 1,408.7 Presence of Light 26.9% 42.3% Speed Limit (mph) 10–25: 0.1% 26–40: 25.7% 41–55: 74.2% >55: 0% 10–25: 5.1% 26–40: 60.8% 41–55: 34.1% >55: 0% Proportion of Male 0.00 1.00 0.65 0.14 0.00 0.87 0.56 0.16 Proportion of Female 0.00 1.00 0.35 0.14 0.00 1.00 0.42 0.16 Proportion of PC 0.00 1.00 0.82 0.13 0.00 1.00 0.92 0.15 Proportion of HV 0.00 1.00 0.15 0.12 0.00 0.35 0.04 0.05 Proportion of MCO 0.00 0.33 0.02 0.04 0.00 0.12 0.02 0.03 Proportion of Young 0.00 1.00 0.15 0.08 0.00 0.50 0.15 0.08 Proportion of Middle 0.00 1.00 0.76 0.10 0.00 1.00 0.75 0.13 Proportion of Senior 0.00 0.56 0.09 0.07 0.00 0.25 0.08 0.06 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 2 0 0.2 0 1 0 - A 0 2 0 7.1 0 1 0 - B 0 6 0.1 0.5 0 4 0.4 0.8 C 0 6 0.2 0.6 0 11 1.2 2.3 PDO 0 13 0.5 1 0 119 5.9 13.7

Table A-5. Four-leg signalized intersections on rural two-lane, two-way highways. Variable Estimation Dataset (MN/68 counts) Validation Dataset (CT/31 counts) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Presence of left-turn lane 33.8% 29.0% Presence of right-turn lane 38.2% 22.6% AADT 1 1,454 18,172 8,713.7 4,131 2,200 16,200 8,829 4,143 AADT 2 392 18,656 4,195.3 3,310.8 300 11,000 3,243.5 2,391.4 Presence of Light 94.1% 54.8% Speed Limit (mph) 10–25: 0% 26–40: 76.5% 41–55: 23.5% >55: 0% 10–25: 3.2% 26–40: 38.7% 41–55: 58.1% >55: 0% Proportion of Male 0.33 0.82 0.60 0.12 0.29 0.88 0.57 0.12 Proportion of Female 0.18 0.67 0.40 0.12 0.12 0.71 0.43 0.12 Proportion of PC 0.42 1.00 0.88 0.09 0.82 1.00 0.95 0.04 Proportion of HV 0.00 0.58 0.10 0.09 0.00 0.18 0.04 0.03 Proportion of MCO 0.00 0.08 0.02 0.02 0.00 0.08 0.01 0.02 Proportion of Young 0.07 0.25 0.15 0.04 0.00 0.30 0.16 0.07 Proportion of Middle 0.57 0.86 0.76 0.07 0.61 0.96 0.77 0.07 Proportion of Senior 0.00 0.23 0.09 0.05 0.00 0.14 0.07 0.04 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 2 0.029 0.241 0 1 0 - A 0 1 0.056 0.235 0 0 0 0 B 0 3 0.368 0.684 0 5 1 1.3 C 0 9 0.765 1.373 0 11 1.8 2.6 PDO 0 12 2.5 2.938 0 77 6.1 14

Table A-6. Rural four-lane undivided highways. Variable Estimation Dataset (CA/176 counts/75.6 miles) Validation Dataset (CT/76 sites/5.35 miles) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Lane Width (<12 ft) 6.8% 14.5% Shoulder Width (ft) 0 14 6.6 3.1 2 14 7.4 3.1 Shoulder Type (Unpaved) 9.7% - AADT 581 38,146 9,147.9 6,682 6,860 33,100 22,403.2 9,181.8 Speed Limit (mph) 10–25: 2.3% 26–40: 0% 41–55: 33% >55: 64.7% 10–25: 0% 26–40: 28.9% 41–55: 71.1% >55: 0% Proportion of Male 0.00 1.00 0.68 0.18 0.38 0.76 0.58 0.11 Proportion of Female 0.00 1.00 0.29 0.14 0.24 0.63 0.42 0.11 Proportion of PC 0.00 1.00 0.78 0.21 0.95 0.98 0.96 0.01 Proportion of HV 0.00 1.00 0.15 0.15 0.02 0.03 0.03 0.00 Proportion of MCO 0.00 0.29 0.03 0.06 0.00 0.02 0.01 0.01 Proportion of Young 0.00 0.38 0.13 0.07 0.07 0.24 0.11 0.04 Proportion of Middle 0.00 1.00 0.78 0.17 0.56 0.88 0.82 0.06 Proportion of Senior 0.00 0.33 0.06 0.05 0.02 0.20 0.07 0.04 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 5 0.1 0.5 0 1 0 - A 0 3 0.2 0.5 0 1 0 - B 0 13 0.7 1.5 0 2 0.1 0.4 C 0 10 0.9 1.7 0 3 0.2 0.6 PDO 0 32 3 4.5 0 12 1.6 2.3

Table A-7. Rural four-lane divided highways. Variable Estimation Dataset (CA/1,072 counts/595.5 miles) Validation Dataset (MN/542 counts/484.75 miles) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Lane Width (<12 ft) 0.9% 3.1% Median Width (ft) <=20: 27.5% 21–40: 21.3% >40: 51.2% <=20: 16.2% 21–40: 7.6% >40: 76.2% Shoulder Width 0 16 8.8 2 0 12 9.2 2.1 Shoulder Type (Unpaved) 1.9% 4.6% AADT 2,800 90,000 19,056.8 13,424.4 74 35,500 11,161.9 6,816.5 Speed Limit (<=55 mph) 7.0% - Proportion of Male 0.00 1.00 0.69 0.17 0.00 1.00 0.63 0.14 Proportion of Female 0.00 1.00 0.30 0.16 0.00 0.72 0.36 0.12 Proportion of PC 0.00 1.00 0.78 0.21 0.00 1.00 0.85 0.13 Proportion of HV 0.00 1.00 0.18 0.18 0.00 0.50 0.12 0.09 Proportion of MCO 0.00 0.17 0.03 0.04 0.00 0.10 0.02 0.02 Proportion of Young 0.00 1.00 0.14 0.10 0.00 0.75 0.15 0.06 Proportion of Middle 0.00 1.00 0.80 0.14 0.00 1.00 0.76 0.11 Proportion of Senior 0.00 0.50 0.05 0.05 0.00 0.30 0.08 0.04 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 5 0.2 0.5 0 3 0.1 0.4 A 0 5 0.3 0.7 0 5 0.2 0.5 B 0 21 1.2 2.1 0 14 1.2 1.9 C 0 42 1.8 3.8 0 31 2.1 3.3 PDO 0 133 5.3 9.4 0 79 6.7 9.4

Table A-8. Three-leg stop-controlled intersections on rural multilane highways. Variable Estimation Dataset (CA/409 counts) Validation Dataset (MN/209 counts) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Presence of left-turn lane N/A 62.2% Presence of right-turn lane N/A 59.3% AADT 1 582 90,000 14,540.4 12,793.7 510 29,618 10,762.1 6,586.7 AADT 2 50 23,111 501.8 1,517.3 50 11,700 979 1,298.6 Presence of Light 27.6% 27.8% Speed Limit (<=55 mph) 17.4% 73.2% Proportion of Male 0.00 1.00 0.65 0.20 0.42 1.00 0.64 0.11 Proportion of Female 0.00 1.00 0.32 0.17 0.00 0.58 0.36 0.11 Proportion of PC 0.00 1.00 0.79 0.22 0.45 1.00 0.86 0.10 Proportion of HV 0.00 1.00 0.14 0.17 0.00 0.55 0.13 0.10 Proportion of MCO 0.00 0.50 0.03 0.05 0.00 0.08 0.02 0.02 Proportion of Young 0.00 1.00 0.13 0.10 0.00 0.33 0.16 0.06 Proportion of Middle 0.00 1.00 0.80 0.18 0.62 1.00 0.77 0.06 Proportion of Senior 0.00 0.33 0.04 0.04 0.00 0.26 0.07 0.03 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 1 0 - 0 1 0 - A 0 2 0 0.2 0 1 0 - B 0 3 0.1 0.3 0 5 0.2 0.6 C 0 4 0.2 0.5 0 5 0.2 0.7 PDO 0 11 0.7 1.5 0 12 0.7 1.5

Table A-9. Four-leg stop-controlled intersections on rural multilane highways. Variable Estimation Dataset (CA/275 counts) Validation Dataset (MN/269 counts) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Presence of left-turn lane N/A 66.9% Presence of right-turn lane N/A 21.6% AADT 1 981 90,000 13,694.7 10,597.7 1,112 44,678 10,338.4 6,699.7 AADT 2 50 8,800 469 864.4 54 8,927 1,141.8 1,234.5 Presence of Light 40.0% 34.2% Speed Limit (<= 55 mph) 13.5% 13.5% Proportion of Male 0.00 1.00 0.69 0.19 0.38 0.85 0.63 0.11 Proportion of Female 0.00 1.00 0.28 0.15 0.15 0.62 0.37 0.11 Proportion of PC 0.00 1.00 0.78 0.20 0.45 1.00 0.86 0.09 Proportion of HV 0.00 1.00 0.15 0.15 0.00 0.55 0.13 0.10 Proportion of MCO 0.00 0.25 0.04 0.05 0.00 0.07 0.01 0.02 Proportion of Young 0.00 1.00 0.13 0.11 0.05 0.44 0.15 0.05 Proportion of Middle 0.00 1.00 0.78 0.18 0.55 0.91 0.77 0.06 Proportion of Senior 0.00 0.33 0.06 0.06 0.00 0.23 0.08 0.04 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 2 0.1 0.3 0 3 0.1 0.3 A 0 2 0.1 0.3 0 2 0.1 0.3 B 0 5 0.2 0.6 0 4 0.3 0.6 C 0 5 0.3 0.8 0 15 0.5 1.3 PDO 0 9 0.9 1.4 0 9 1.1 1.7

Table A-10. Four-leg signalized intersections on rural multilane highways. Variable Estimation Dataset (CA/71 counts) Validation Dataset (MN/54 counts) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Presence of left-turn lane N/A 72.2% Presence of right-turn lane N/A 42.6% AADT 1 1,001 46,000 17,459.9 8,463.5 5,600 2,2442 13,088.6 4,637.6 AADT 2 50 17,800 2,639.5 3,309.7 399 1,1152 4,002.5 2,740.7 Presence of Light 100% 94.4% Speed Limit (<= 55 mph) 23.9% 85.2% Proportion of Male 0.00 0.91 0.63 0.14 0.45 0.79 0.60 0.09 Proportion of Female 0.09 1.00 0.37 0.14 0.21 0.55 0.40 0.09 Proportion of PC 0.38 1.00 0.88 0.11 0.75 1.00 0.90 0.06 Proportion of HV 0.00 0.57 0.09 0.09 0.00 0.24 0.09 0.05 Proportion of MCO 0.00 0.23 0.03 0.04 0.00 0.07 0.01 0.02 Proportion of Young 0.00 1.00 0.18 0.13 0.00 0.25 0.14 0.05 Proportion of Middle 0.00 1.00 0.78 0.13 0.62 1.00 0.78 0.07 Proportion of Senior 0.00 0.91 0.63 0.14 0.00 0.26 0.08 0.04 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 1 0 - 0 1 0.1 - A 0 4 0.2 0.6 0 1 0 - B 0 4 0.4 0.7 0 3 0.5 0.8 C 0 6 1 1.5 0 6 1.4 1.6 PDO 0 14 2.8 2.8 0 14 3.6 3.8

Table A-11. Urban and suburban two-lane undivided arterials. Variable Estimation Dataset (OH/3,608 counts/2,526.1 miles) Validation Dataset (NC/2,605 counts/1,688.43 miles) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. AADT 120 35,360 7,146.2 4,255.9 210 47,000 8,122.1 5,122.2 Speed Limit (mph) 10–25: 10% 26–40: 43.6% 41–55: 46.4% >55: 0% 10–25: 0.2% 26–40: 19.1% 41–55: 17.9% >55: 62.8% Proportion of Male 0.00 1.00 0.54 0.12 0.00 1.00 0.49 0.21 Proportion of Female 0.00 1.00 0.45 0.12 0.00 1.00 0.45 0.21 Proportion of PC 0.00 1.00 0.94 0.07 0.00 1.00 0.91 0.22 Proportion of HV 0.00 0.55 0.04 0.04 0.00 1.00 0.03 0.06 Proportion of MCO 0.00 1.00 0.01 0.02 0.00 0.50 0.01 0.03 Proportion of Young 0.00 1.00 0.17 0.06 0.00 1.00 0.16 0.13 Proportion of Middle 0.00 1.00 0.76 0.08 0.00 1.00 0.72 0.22 Proportion of Senior 0.00 1.00 0.07 0.04 0.00 1.00 0.06 0.09 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 5 0.1 0.3 0 2 0 0.2 A 0 9 0.5 1 0 3 0 0.2 B 0 39 1.7 3 0 8 0.2 0.6 C 0 48 2 3.6 0 17 0.7 1.4 PDO 0 249 12.9 18.1 0 45 2 3.5

Table A-12. Urban and suburban three-lane arterials with a center two-way left-turn lane. Variable Estimation Dataset (OH/141 counts/44.98 miles) Validation Dataset (NC/74 counts/16.94 miles) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. AADT 360 25,953 9,895.3 4,992.2 2,400 33,000 13,875.7 6,255.8 Speed Limit (mph) 10–25: 19.1% 26–40: 57.5% 41–55: 23.4% >55: 0% 10–25: 0% 26–40: 16.2% 41–55: 20.3% >55: 63.5% Proportion of Male 0.31 1.00 0.53 0.10 0.00 0.79 0.51 0.14 Proportion of Female 0.00 0.69 0.47 0.10 0.00 0.76 0.47 0.13 Proportion of PC 0.87 1.00 0.96 0.02 0.00 1.00 0.95 0.12 Proportion of HV 0.00 0.11 0.03 0.02 0.00 0.17 0.03 0.03 Proportion of MCO 0.00 0.04 0.01 0.01 0.00 0.07 0.01 0.01 Proportion of Young 0.00 0.44 0.16 0.06 0.00 0.38 0.18 0.08 Proportion of Middle 0.54 1.00 0.78 0.07 0.00 1.00 0.74 0.12 Proportion of Senior 0.00 0.18 0.07 0.03 0.00 0.25 0.06 0.04 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 3 0.1 0.4 0 1 0 - A 0 4 0.3 0.7 0 1 0 - B 0 14 1.4 2.1 0 2 0.1 0.3 C 0 16 1.8 2.7 0 4 0.5 0.8 PDO 0 171 12.2 18.6 0 15 1.8 3

Table A-13. Urban and suburban four-lane undivided arterials. Variable Estimation Dataset (OH/1,663 counts/922.85 miles) Validation Dataset (NC/935 counts/486.845 miles) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. AADT 1,250 48,400 14,969.6 7,096.7 430 48,000 19,319.9 8,418.5 Speed Limit (mph) 10–25: 19.4% 26–40: 59.3% 41–55: 20.9% >55: 0.4% 10–25: 0.3% 26–40: 11.7% 41–55: 30.1% >55: 57.9% Proportion of Male 0.00 1.00 0.51 0.09 0.00 1.00 0.50 0.13 Proportion of Female 0.00 1.00 0.49 0.09 0.00 1.00 0.49 0.13 Proportion of PC 0.00 1.00 0.96 0.04 0.00 1.00 0.95 0.09 Proportion of HV 0.00 1.00 0.03 0.03 0.00 0.42 0.03 0.03 Proportion of MCO 0.00 0.08 0.01 0.01 0.00 0.33 0.01 0.02 Proportion of Young 0.00 0.49 0.17 0.05 0.00 1.00 0.17 0.08 Proportion of Middle 0.49 1.00 0.77 0.06 0.00 1.00 0.76 0.11 Proportion of Senior 0.00 0.21 0.07 0.03 0.00 0.40 0.06 0.04 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 4 0.1 0.4 0 2 0 0.2 A 0 14 0.8 1.5 0 2 0 0.2 B 0 151 3.7 7.2 0 8 0.4 0.9 C 0 104 5.6 9.3 0 31 1.5 2.7 PDO 0 611 31.1 45.2 0 108 5 8

Table A-14. Urban and suburban four-lane divided arterials. Variable Estimation Dataset (OH/862 counts/484.81 miles) Validation Dataset (NC/1332 counts/550 miles) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Median Width (ft) <=20: 56.5% 21-40: 24.0% >40: 19.5% <=20: 74.7% 21-40: 21.5% >40: 3.8% AADT 820 71,560 16,559.3 9,123.8 2,000 64,000 23,686.6 11,193.2 Speed Limit (mph) 10–25: 2.9% 26–40: 24.2% 41–55: 54.9% >55: 18% 10–25: 0% 26–40: 3.3% 41–55: 20.4% >55: 76.3% Proportion of Male 0.00 1.00 0.55 0.12 0.00 1.00 0.51 0.14 Proportion of Female 0.00 1.00 0.44 0.12 0.00 0.83 0.47 0.13 Proportion of PC 0.00 1.00 0.93 0.12 0.00 1.00 0.94 0.12 Proportion of HV 0.00 1.00 0.05 0.07 0.00 0.36 0.03 0.03 Proportion of MCO 0.00 0.06 0.01 0.01 0.00 0.08 0.01 0.01 Proportion of Young 0.00 0.47 0.15 0.05 0.00 0.59 0.17 0.08 Proportion of Middle 0.00 1.00 0.78 0.10 0.00 1.00 0.77 0.12 Proportion of Senior 0.00 0.29 0.06 0.03 0.00 0.33 0.05 0.04 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 2 0.1 0.3 0 1 0 - A 0 9 0.4 0.9 0 2 0 0.2 B 0 44 1.9 3.4 0 6 0.2 0.6 C 0 78 2.4 4.9 0 27 0.9 2 PDO 0 366 16.6 28.2 0 81 3 5.9

Table A-15. Urban and suburban five-lane arterials with a center two-way left-turn lane. Variable Estimation Dataset (OH/50 counts/17.34 miles) Validation Dataset (NC/14 counts/2.36 miles) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. AADT 8,200 61,630 20,190.9 11,075.8 8,500 46,000 30,892.9 11,235.6 Speed Limit (mph) 10–25: 18% 26–40: 68% 41–55: 14% >55: 0% 10–25: 0% 26–40: 21.4% 41–55: 57.2% >55: 21.4% Proportion of Male 0.33 0.70 0.55 0.08 0.00 0.70 0.44 0.19 Proportion of Female 0.30 0.67 0.45 0.08 0.00 0.80 0.49 0.20 Proportion of PC 0.91 0.99 0.97 0.02 0.00 1.00 0.89 0.25 Proportion of HV 0.01 0.08 0.03 0.02 0.00 0.09 0.03 0.02 Proportion of MCO 0.00 0.02 0.01 0.01 0.00 0.02 0.01 0.01 Proportion of Young 0.06 0.34 0.16 0.05 0.00 0.24 0.16 0.06 Proportion of Middle 0.63 0.87 0.78 0.05 0.00 0.84 0.72 0.20 Proportion of Senior 0.02 0.16 0.06 0.03 0.00 0.10 0.04 0.03 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 1 0.1 0.2 0 0 0 - A 0 8 0.5 1.2 0 1 0.1 - B 0 13 2.8 3.5 0 3 0.4 0.9 C 0 39 4 6 0 15 3.2 4.4 PDO 0 163 24.3 28.9 0 28 5.9 7.8

Table A-16. Three-leg stop-controlled intersections on urban and suburban arterials. Variable Estimation Dataset (CT/798 counts) Validation Dataset (MN/794 counts) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Number of approaches with exclusive left-turn lanes 0: 93.7% 1:5.0% 2:1.1% 3:0.1% 0: 74.3% 1: 17.9% 2: 7.2% 3: 0.6% Number of approaches with exclusive right-turn lanes 0: 95.7% 1:3.3% 2:1.0% 3:0.0% 0: 53.6% 1:43.8% 2:2.5% 3: 0.0% Intersection Median No med: 87.8%, Partial med: 11.6%, all med: 0.5% N/A Presence of Light 68.2% 62.2% Driveway type Major 0.4%, Minor 44.1%, None 55.5% N/A AADT1 550 34,400 9,708.5 5,248.1 1,350 6,0421 14,887.9 9,988.3 AADT2 50 12,900 2,532.5 2,182 50 19,076 1,097.8 1,640.6 Speed Limit (mph) 10–25: 13.8% 26–40: 71.5% 41–55: 15.6% >55: 0% 10–25: 0% 26–40: 44.1% 41–55: 50.7% >55: 5.2% Proportion of Male 0.00 1.00 0.54 0.14 0.23 1.00 0.55 0.13 Proportion of Female 0.00 0.82 0.46 0.14 0.00 0.77 0.45 0.13 Proportion of PC 0.00 1.00 0.96 0.04 0.00 1.00 0.94 0.05 Proportion of HV 0.00 0.33 0.03 0.02 0.00 1.00 0.05 0.05 Proportion of MCO 0.00 0.15 0.01 0.02 0.00 0.08 0.01 0.02 Proportion of Young 0.00 0.50 0.15 0.06 0.00 1.00 0.16 0.06 Proportion of Middle 0.00 1.00 0.76 0.08 0.00 1.00 0.78 0.06 Proportion of Senior 0.00 0.80 0.08 0.06 0.00 0.19 0.06 0.03 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 1 0 - 0 1 0 - A 0 2 0 0.2 0 2 0 0.1 B 0 14 0.6 1.3 0 7 0.1 0.5 C 0 23 1.0 2.1 0 6 0.3 0.7 PDO 0 117 5.4 11.3 0 15 0.8 1.6

Table A-17. Three-leg signalized intersections on urban and suburban arterials. Variable Estimation Dataset (CT/498 counts) Validation Dataset (MN/67 counts) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Number of approaches with exclusive left-turn lanes 0: 34.7% 1: 33.7% 2: 27.9% 3: 3.6% 0: 13.4% 1: 34.3% 2: 44.8% 3: 7.5% Left-turn signal phasing Permissive only: 23.9% Protected and Permissive: 73.7% Protected only: 2.4% N/A Number of approaches with exclusive right-turn lanes 0: 43.6% 1: 37.5% 2: 18.9% 3: 0% 0: 25.4% 1: 59.7% 2: 14.9% 3: 0% Number of approaches with no right turn on red 0: 78.3% 1: 16.7% 2: 4.8% 3: 0.2% N/A Intersection Median No med: 62.1%, Partial med: 34.9%, all med: 3.0% N/A Presence of Light 85.5% Yes 97% Driveway type Major 1.6%, Minor 51.6%, None 46.8% N/A AADT1 3,900 68,200 16,366.9 7,128.5 6,355 58,881 20,662.8 10,766 AADT2 300 43,300 7,009.3 5,703.8 99 17,700 4,864.3 4,105.9 Speed Limit (mph) 10–25: 13.9% 26–40: 70.9% 41–55: 14.8% >55: 0.4% 10–25: 0% 26–40: 47.8% 41–55: 50.7% >55: 1.5% Proportion of Male 0.13 0.84 0.53 0.12 0.28 0.84 0.53 0.12 Proportion of Female 0.16 0.87 0.47 0.12 0.16 0.72 0.47 0.12 Proportion of PC 0.84 1.00 0.96 0.02 0.85 0.99 0.94 0.04 Proportion of HV 0.00 0.14 0.03 0.02 0.00 0.14 0.05 0.03 Proportion of MCO 0.00 0.11 0.01 0.01 0.00 0.05 0.01 0.01 Proportion of Young 0.00 0.48 0.14 0.06 0.08 0.31 0.15 0.04 Proportion of Middle 0.44 0.94 0.78 0.07 0.61 0.88 0.79 0.06 Proportion of Senior 0.00 0.29 0.08 0.04 0.00 0.20 0.06 0.03 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 1 0 - 0 1 0 - A 0 3 0.1 0.3 0 1 0.1 - B 0 11 0.7 1.4 0 3 0.5 0.9 C 0 35 1.3 2.9 0 9 1.6 1.9 PDO 0 90 6.1 11.5 0 14 3.7 3.8

Table A-18. Four-leg stop-controlled intersections on urban and suburban arterials. Variable Estimation Dataset (CT/262 counts) Validation Dataset (MN/528 counts) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Number of approaches with left-turn lanes 0: 93.5% 1: 4.2% 2: 2.3% 3: 0% 4: 0% 0: 62.3% 1: 4.5% 2: 30.7% 3: 1.1% 4: 1.3% Number of approaches with right-turn lanes 0: 93.1% 1: 5.7% 2:1.1% 3: 0% 4: 0% 0: 72.5% 1: 13.8% 2: 12.3% 3: 0.8% 4: 0.6% Intersection Median No med: 85.5% Partial med: 13.0% All med: 1.5% N/A Presence of Light 79.8% 78.8% Driveway type Major 7.6% Minor 21.4% None 71.0% N/A AADT1 1,300 27,000 8,622.9 5,078.1 910 53,212 14,024.4 9,378.5 AADT2 60 18,000 2,753.6 2,620.4 55 14,000 1,427.8 1,496.5 Speed Limit (mph) 10–25: 14.9% 26–40: 62.7% 41–55: 22.5% >55: 0% 10–25: 0% 26–40: 58.8% 41–55: 35.2% >55: 6.1% Proportion of Male 0.17 1.00 0.54 0.14 0.24 1.00 0.55 0.13 Proportion of Female 0.00 0.83 0.46 0.14 0.00 0.76 0.45 0.13 Proportion of PC 0.79 1.00 0.96 0.04 0.00 1.00 0.92 0.07 Proportion of HV 0.00 0.20 0.03 0.03 0.00 1.00 0.06 0.07 Proportion of MCO 0.00 0.20 0.01 0.02 0.00 0.08 0.01 0.01 Proportion of Young 0.00 0.41 0.15 0.06 0.00 0.37 0.17 0.06 Proportion of Middle 0.17 1.00 0.76 0.08 0.51 1.00 0.76 0.07 Proportion of Senior 0.00 0.67 0.09 0.06 0.00 0.22 0.06 0.03 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 1 0 - 0 1 0 - A 0 3 0 0.2 0 2 0 0.2 B 0 12 0.7 1.5 0 5 0.3 0.7 C 0 16 1 2.1 0 7 0.7 1.1 PDO 0 56 4.3 8.9 0 19 1.6 2.5

Table A-19. Four-leg signalized intersections on urban and suburban arterials. Variable Estimation Dataset (CT/986 counts) Validation Dataset (MN/632 counts) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Number of approaches with exclusive left-turn lanes 0: 33.9% 1: 14.4% 2: 20.6% 3: 14.8% 4: 16.3% 0: 16% 1: 1.9% 2: 32.6% 3: 7.3% 4: 42.2% Left-turn signal phasing Permissive only: 26.8% Protected and Permissive: 69.8% Protected only: 3.4% N/A Number of approaches with exclusive right-turn lanes 0: 51.3% 1: 30.9% 2: 13.1% 3: 3.8% 4: 0.8% 0: 76.7% 1: 12.8% 2: 9.8% 3: 0.5% 4: 0.2% Number of approaches with no right turn on red 0: 55.6% 1: 18.4% 2: 12.6% 3: 6.5% 4: 7.0% N/A Intersection Median No med: 75.2% Partial med: 23.5% all med: 1.2% N/A Presence of Light 87.9% 98.3% Driveway type Major 16.5% Minor 19.5% None 64.0% N/A AADT1 2,300 41,100 15,886.2 6,657.8 2,135 63,000 21,142.4 10,690.3 AADT2 200 34,700 7,435.6 4,946.2 70 31,500 6,943.3 5,355.6 Speed Limit (mph) 10–25: 18.4% 26–40: 68.8% 41–55: 12.7% >55: 0.1% 10–25: 0% 26–40: 53% 41–55: 42.4% >55: 4.6% Proportion of Male 0.21 1.00 0.53 0.11 0.21 0.81 0.55 0.11 Proportion of Female 0.00 0.79 0.47 0.11 0.19 0.79 0.45 0.11 Proportion of PC 0.64 1.00 0.96 0.03 0.76 1.00 0.94 0.04 Proportion of HV 0.00 0.36 0.03 0.03 0.00 0.24 0.05 0.03 Proportion of MCO 0.00 0.11 0.01 0.01 0.00 0.07 0.01 0.01 Proportion of Young 0.00 0.48 0.14 0.05 0.00 0.50 0.16 0.06 Proportion of Middle 0.47 1.00 0.79 0.06 0.47 1.00 0.77 0.07 Proportion of Senior 0.00 0.26 0.08 0.04 0.00 0.27 0.06 0.03 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 2 0 0.1 0 2 0 0.2 A 0 2 0.1 0.3 0 3 0.1 0.4 B 0 15 0.9 1.6 0 6 0.8 1.1 C 0 45 1.9 3.8 0 24 2.6 3 PDO 0 123 6 11.6 0 51 6.4 6.9

Table A-20. Rural four-lane freeways. Variable Estimation Dataset (CA/1286 counts/1187.37 miles) Validation Dataset (OH/391 counts/431.71 miles) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Lane Width (<12 ft) 0.2% N/A Inside Shoulder Width (paved) 0 29 5.8 2.1 1 16 4.5 1.7 Outside Shoulder Width (paved) 0 36 9.9 2.2 1 14 4.5 1.5 Median Width 6 99 66.7 27.2 4 99 63.1 18.4 AADT 200 93,000 26,579.3 14,628.2 4,870 54,180 31,005.4 9,362.3 Speed Limit (<= 65 mph) 10.8% 14.8% Proportion of Male 0.00 1.00 0.72 0.13 0.43 0.90 0.70 0.10 Proportion of Female 0.00 1.00 0.27 0.12 0.10 0.57 0.30 0.10 Proportion of PC 0.00 1.00 0.69 0.18 0.17 0.97 0.71 0.12 Proportion of HV 0.00 0.81 0.29 0.17 0.03 0.83 0.29 0.12 Proportion of MCO 0.00 0.23 0.02 0.03 0.00 0.08 0.01 0.01 Proportion of Young 0.00 1.00 0.13 0.08 0.04 0.24 0.11 0.04 Proportion of Middle 0.00 1.00 0.82 0.10 0.73 0.93 0.84 0.04 Proportion of Senior 0.00 0.40 0.05 0.04 0.02 0.09 0.04 0.02 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 8 0.3 0.7 0 5 0.2 0.6 A 0 13 0.5 1.1 0 13 0.9 1.6 B 0 55 2.1 3.5 0 33 3.7 5.3 C 0 69 2.5 4.1 0 27 2.6 3.7 PDO 0 225 9.7 14.2 0 241 30 39.7

Table A-21. Rural six-lane freeways. Variable Estimation Dataset (CA/197 counts/109.34 miles) Validation Dataset (OH/174 counts/200.52 miles) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Lane Width (<12 ft) 0.5% N/A Inside Shoulder Width (paved) 0 17 8.3 3.1 4 15 11.5 2.9 Outside Shoulder Width (paved) 0 18 9.9 1.8 10 13 10.6 0.9 Median Width 10 99 49.4 22.6 3 99 26.7 26 AADT 13,000 178,000 69,658.3 35,389.1 31,820 75,040 44,204.7 8,782.9 Speed Limit (<= 65 mph) 14.2% 1.7% Proportion of Male 0.33 0.87 0.68 0.11 0.35 0.85 0.71 0.09 Proportion of Female 0.13 0.67 0.32 0.11 0.15 0.65 0.29 0.09 Proportion of PC 0.45 1.00 0.80 0.13 0.44 0.94 0.70 0.11 Proportion of HV 0.00 0.50 0.18 0.13 0.06 0.55 0.29 0.11 Proportion of MCO 0.00 0.10 0.02 0.02 0.00 0.10 0.01 0.02 Proportion of Young 0.00 0.23 0.13 0.04 0.04 0.24 0.13 0.04 Proportion of Middle 0.67 1.00 0.83 0.05 0.73 0.91 0.84 0.04 Proportion of Senior 0.00 0.15 0.04 0.03 0.02 0.09 0.04 0.02 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 5 0.3 0.7 0 3 0.2 0.6 A 0 6 0.7 1.1 0 9 1.2 1.8 B 0 31 3.3 4.4 0 69 6.5 8.7 C 0 59 5.7 8 0 34 4.5 5.3 PDO 0 147 18.2 21.9 0 321 49.7 56.8

Appendix 57   Table A-22, Rural eight-lane freeways. Variable Estimation Dataset (CA/144 counts/96.26 miles) Roadway. Var. Min. Max. Mean Std. Dev. Lane Width (<12 ft) 0% Inside Shoulder Width (paved) 0 17 8.2 1.5 Outside Shoulder Width (paved) 0 13 9.9 1.2 Median Width 18 99 54.2 21.9 AADT 40,281 178,000 105,086.1 31,787.3 Speed Limit (<= 65 mph) 4.9% Proportion of Male 0.00 0.83 0.68 0.12 Proportion of Female 0.00 0.64 0.31 0.10 Proportion of PC 0.00 0.95 0.77 0.15 Proportion of HV 0.00 0.58 0.21 0.14 Proportion of MCO 0.00 0.10 0.02 0.02 Proportion of Young 0.00 0.22 0.12 0.04 Proportion of Middle 0.00 0.91 0.83 0.08 Proportion of Senior 0.00 0.07 0.03 0.01 Crash Counts Min. Max. Mean Std. Dev. K 0 7 0.6 1.2 A 0 7 1.2 1.6 B 0 48 5.8 6.7 C 0 100 9.4 12.2 PDO 0 198 33.8 34.6 Note: No data available for validation.

Table A-23. Urban four-lane freeways. Variable Estimation Dataset (CA/1393 counts/612.636 miles) Validation Dataset (OH/1612 counts/776.77 miles) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Lane Width (<12 ft) 0.3% N/A Inside Shoulder Width (paved) 0 23 5.5 2.5 0 26 4.4 2.2 Outside Shoulder Width (paved) 0 30 9 2 0 26 4.4 2.2 Median Width 6 99 50.1 23.9 1 99 42.6 27.7 AADT 200 308,000 50,382 32,401.2 4,870 124,240 32,632.1 19,908.5 Speed Limit (<= 65 mph) 16.6% 73.6% Proportion of Male 0.00 1.00 0.60 0.12 0.00 1.00 0.60 0.12 Proportion of Female 0.00 1.00 0.40 0.12 0.00 1.00 0.40 0.12 Proportion of PC 0.26 1.00 0.88 0.11 0.19 1.00 0.87 0.10 Proportion of HV 0.00 0.64 0.10 0.11 0.00 0.81 0.12 0.10 Proportion of MCO 0.00 0.17 0.02 0.02 0.00 0.08 0.01 0.01 Proportion of Young 0.00 0.10 0.01 0.01 0.00 0.27 0.14 0.04 Proportion of Middle 0.00 0.07 0.01 0.01 0.59 1.00 0.81 0.05 Proportion of Senior 0.00 0.41 0.16 0.06 0.00 0.18 0.05 0.02 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 3 0.2 0.5 0 3 0.1 0.3 A 0 8 0.6 0.9 0 13 0.7 1.3 B 0 30 2.9 3.5 0 98 2.8 5 C 0 97 6.1 8.8 0 81 2.7 5.1 PDO 0 223 18.7 22.9 0 358 20.4 27.4

Table A-24. Urban six-lane freeways. Variable Estimation Dataset (CA/1191 counts/504.34 miles) Validation Dataset (OH/781 counts/438.03 miles) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Lane Width (<12 ft) 1.8% N/A Inside Shoulder Width (paved) 0 37 7.2 4 0 24 9.1 4 Outside Shoulder Width (paved) 0 22 9.3 2.8 0 20 10 1.7 Median Width 4 99 44.7 24.5 0 24 9.1 4 AADT 5,300 345,000 103,282.5 47,853.7 12,770 157,070 73,241.2 28,074.7 Speed Limit (<= 65 mph) 7.5% 83.2% Proportion of Male 0.21 1.00 0.60 0.10 0.26 0.89 0.60 0.11 Proportion of Female 0.00 0.79 0.40 0.10 0.11 0.74 0.40 0.11 Proportion of PC 0.44 1.00 0.89 0.08 0.35 0.99 0.87 0.11 Proportion of HV 0.00 0.56 0.09 0.08 0.01 0.65 0.12 0.11 Proportion of MCO 0.00 0.13 0.02 0.02 0.00 0.07 0.01 0.01 Proportion of Young 0.00 0.33 0.16 0.04 0.04 0.29 0.14 0.04 Proportion of Middle 0.56 1.00 0.81 0.05 0.67 0.93 0.83 0.04 Proportion of Senior 0.00 0.15 0.03 0.02 0.01 0.12 0.03 0.02 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 8 0.4 0.7 0 3 0.2 0.5 A 0 11 1 1.4 0 19 1.5 2.1 B 0 76 5.6 6.2 0 64 7.1 8.1 C 0 193 14 15.9 0 75 7.8 9.8 PDO 0 501 41.9 46.2 0 432 52 54.3

Table A-25. Urban eight-lane freeways. Variable Estimation Dataset (CA/1519 counts/513.48 miles) Validation Dataset (OH/245 counts/112.34 miles) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Lane Width (<12 ft) 1.8% N/A Inside Shoulder Width (paved) 0 26 8.4 3.8 3 25 10.7 4.2 Outside Shoulder Width (paved) 0 17 9.6 1.8 0 20 10.3 2.1 Median Width 6 99 33.6 20.4 2 99 17.2 28.6 AADT 3,200 362,778 159,967.8 53,914.4 35,292 181,830 109,461.6 25,482.5 Speed Limit (<= 65 mph) 2.4% 100% Proportion of Male 0.22 0.88 0.60 0.09 0.29 0.80 0.57 0.09 Proportion of Female 0.12 0.78 0.40 0.09 0.20 0.71 0.43 0.09 Proportion of PC 0.58 1.00 0.91 0.05 0.55 0.99 0.92 0.06 Proportion of HV 0.00 0.41 0.07 0.05 0.01 0.45 0.07 0.06 Proportion of MCO 0.00 0.11 0.02 0.02 0.00 0.03 0.01 0.01 Proportion of Young 0.05 0.28 0.15 0.04 0.07 0.21 0.14 0.03 Proportion of Middle 0.68 0.93 0.83 0.04 0.76 0.89 0.84 0.03 Proportion of Senior 0.00 0.13 0.03 0.01 0.01 0.08 0.03 0.01 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 7 0.3 0.7 0 5 0.3 0.6 A 0 11 1.1 1.4 0 17 2.2 2.8 B 0 64 6.8 6.6 0 128 10 14.2 C 0 241 18.3 19.9 0 127 14.8 19.6 PDO 0 646 55.4 62.7 1 824 72.2 95

Table A-26. Urban ten-lane freeways. Variable Estimation Dataset (CA/889 counts/253.73 miles) Validation Dataset (OH/25 counts/11.94 miles) Roadway. Var. Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. Lane Width (<12 ft) 24.1% N/A Inside Shoulder Width (paved) 0 28 6.5 4.2 3 25 17.7 7.4 Outside Shoulder Width (paved) 0 13 9.6 1.3 10 20 15.6 4.96 Median Width 6 99 22.4 18.6 3 70 15.2 20.9 AADT 18,408 365,000 20,8313.9 52,344.6 71,570 197,701 123,737.6 32,700.8 Speed Limit (<= 65 mph) 1.7% 100% Proportion of Male 0.30 0.82 0.60 0.07 0.38 0.62 0.49 0.07 Proportion of Female 0.18 0.70 0.40 0.07 0.38 0.63 0.51 0.07 Proportion of PC 0.68 0.98 0.91 0.04 0.87 0.97 0.93 0.03 Proportion of HV 0.01 0.28 0.06 0.04 0.03 0.13 0.07 0.03 Proportion of MCO 0.00 0.09 0.02 0.02 0.00 0.03 0.00 0.01 Proportion of Young 0.06 0.27 0.15 0.03 0.10 0.18 0.13 0.02 Proportion of Middle 0.70 0.91 0.82 0.03 0.77 0.87 0.82 0.03 Proportion of Senior 0.01 0.09 0.03 0.01 0.02 0.08 0.05 0.02 Crash Counts Min. Max. Mean Std. Dev. Min. Max. Mean Std. Dev. K 0 5 0.3 0.7 0 1 0.2 0.4 A 0 10 1.2 1.5 0 14 2.5 3.1 B 0 58 7.9 7.1 1 46 9 10.1 C 0 267 23.8 24.6 1 95 14.4 20 PDO 1 711 73.3 73.3 8 273 58.4 55.2

Abbreviations and acronyms used without denitions in TRB publications: A4A Airlines for America AAAE American Association of Airport Executives AASHO American Association of State Highway Officials AASHTO American Association of State Highway and Transportation Officials ACI–NA Airports Council International–North America ACRP Airport Cooperative Research Program ADA Americans with Disabilities Act APTA American Public Transportation Association ASCE American Society of Civil Engineers ASME American Society of Mechanical Engineers ASTM American Society for Testing and Materials ATA American Trucking Associations CTAA Community Transportation Association of America CTBSSP Commercial Truck and Bus Safety Synthesis Program DHS Department of Homeland Security DOE Department of Energy EPA Environmental Protection Agency FAA Federal Aviation Administration FAST Fixing America’s Surface Transportation Act (2015) FHWA Federal Highway Administration FMCSA Federal Motor Carrier Safety Administration FRA Federal Railroad Administration FTA Federal Transit Administration GHSA Governors Highway Safety Association HMCRP Hazardous Materials Cooperative Research Program IEEE Institute of Electrical and Electronics Engineers ISTEA Intermodal Surface Transportation Efficiency Act of 1991 ITE Institute of Transportation Engineers MAP-21 Moving Ahead for Progress in the 21st Century Act (2012) NASA National Aeronautics and Space Administration NASAO National Association of State Aviation Officials NCFRP National Cooperative Freight Research Program NCHRP National Cooperative Highway Research Program NHTSA National Highway Traffic Safety Administration NTSB National Transportation Safety Board PHMSA Pipeline and Hazardous Materials Safety Administration RITA Research and Innovative Technology Administration SAE Society of Automotive Engineers SAFETEA-LU Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (2005) TCRP Transit Cooperative Research Program TEA-21 Transportation Equity Act for the 21st Century (1998) TRB Transportation Research Board TSA Transportation Security Administration U.S. DOT United States Department of Transportation

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