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Appendix B. Site Data Tables and Figures

In this appendix are the data tables and figures for each site. Each curve has three tables and two figures representing the data collected during the "before" and "1 month after" periods. The first two tables are the speed statistics collected at the PC and CC. The statistics compare the before data to 1 month after, with a negative change representing a reduction. The fraction of vehicles exceeding the speed limit change shows a percentage change in the vehicles exceeding the speed limit between the data collection periods. Also in those tables are speed statistics using the tracking methodology described in the literature review. The third table contains the statistics collected from the tracking methodology and shows the speed reductions that occurred from upstream to the respective point in the curve.

The figures are graphical representations of the data shown in the tables. One figure shows the vehicles mean and 85th percentile speeds at the data collection points, while the other figure shows the change in vehicles exceeding the speed limit at the data collection points.

Iowa Highway 144

Table 8. Results for Iowa - Hwy 144 at PC.

  Before 1 Month Change

ADT

1435

1408

-27

Sample

717

708

Upstream Mean Speed

60.0

58.9

-1.1

Mean Speed

50.7

49.2

-1.5

Standard Deviation

5.2

5.8

85th Percentile Speed

56

55

-1

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.61

0.49

-19.7%

Percentage of Vehicles 10+ Over Limit

0.24

0.16

-33.3%

Percentage of Vehicles 15+ Over Limit

0.04

0.04

0.0%

Percentage of Vehicles 20+ Over Limit

0.00

0.01

0.0%

Tracking Data

Sample

705

700

Upstream Mean Speed

60.0

59.1

-0.9

Mean Speed

50.7

49.3

-1.4

Standard Deviation

5.2

5.5

85th Percentile Speed

56

55

-1

 

Table 9. Results for Iowa - Hwy 144 at CC.

  Before 1 Month Change

ADT

1468

1428

-40

Sample

718

713

 

Upstream Mean Speed

60.0

58.9

-1.1

Mean Speed

48

45.9

-2.1

Standard Deviation

6.2

6.3

85th Percentile Speed

53

51

-2

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.42

0.26

-38.1%

Percentage of Vehicles 10+ Over Limit

0.12

0.05

-58.3%

Percentage of Vehicles 15+ Over Limit

0.01

0.01

0.0%

Percentage of Vehicles 20+ Over Limit

0.00

0.00

0.0%

Tracking Data

Sample

705

700

Upstream Mean Speed

60.0

59.1

-0.9

Mean Speed

48.3

46.0

-2.3

Standard Deviation

5.6

6

 

85th Percentile Speed

53

51

-2

Table 10. Speed Reduction for Iowa - Hwy 144.

  Before 1 Month Change

Mean Speed Reduction Upstream to PC

9

9.7

0.5

Mean Speed Reduction Upstream to CC

11.7

13.0

1.3

Mean Speed Reduction PC to CC

2.5

3.3

0.8

85th Percentile Speed Reduction Upstream to PC

14

15

1

85th Percentile Speed Reduction Upstream to CC

17

18

1

85th Percentile Speed Reduction PC to CC

5

5

0

 

Iowa (Hwy 144)

an image that shows Iowa Highway 144 curve warning arrow with 45 mile per hour curve advisory speed Graph: Iowa Highway 144 impact on mean and 85th percentile speeds for upstream (55 mile per hour speed limit), point of curvature (45 mile per hour advisory speed), and center of curve before implementation and 1 month after
Figure 45. Graph. Impact on vehicle speed - Iowa Hwy 144.

 

Map: Location of sign for southbound traffic on Iowa Highway 144 Bar chart: Change in upstream percentile vehicle speeds on Iowa Highway 144 at 1 month Bar chart: Change in point of curvature percentile vehicle speeds on Iowa Highway 144 at 1 month Bar chart: Change in center of curvature percentile vehicle speeds on Iowa Highway 144 at 1 month
Figure 46. Map and graphs. Location and change in percentile vehicle speed - Iowa Hwy 144.

Missouri Highway 221

Table 11. Results for Missouri - Hwy 221 at PC

  Before 1 Month Change

ADT

5277

5158

-119

Sample

2566

2523

 

Upstream Mean Speed

52.2

52.8

0.6

Mean Speed

51.7

50.2

-1.5

Standard Deviation

4.7

4.8

 

85th Percentile Speed

56

55

-1

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.94

0.88

-6.4%

Percentage of Vehicles 10+ Over Limit

0.70

0.58

-17.1%

Percentage of Vehicles 15+ Over Limit

0.25

0.17

-32.0%

Percentage of Vehicles 20+ Over Limit

0.04

0.02

-50.0%

Tracking Data

Sample

2501

2459

 

Upstream Mean Speed

52.2

52.8

0.6

Mean Speed

51.7

50.2

-1.5

Standard Deviation

4.7

4.8

 

85th Percentile Speed

57

55

-2

 

Table 12. Results for Missouri - Hwy 221 at CC.

  Before 1 Month Change

ADT

5274

5169

-105

Sample

2559

2522

 

Upstream Mean Speed

52.2

52.8

0.6

Mean Speed

48.3

48.6

0.3

Standard Deviation

4.4

4.6

 

85th Percentile Speed

53

53

0

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.82

0.82

0.0%

Percentage of Vehicles 10+ Over Limit

0.38

0.42

10.5%

Percentage of Vehicles 15+ Over Limit

0.07

0.09

28.6%

Percentage of Vehicles 20+ Over Limit

0.01

0.01

0.0%

Tracking Data

Sample

2501

2459

 

Upstream Mean Speed

52.2

52.8

0.6

Mean Speed

48.3

48.6

0.3

Standard Deviation

4.4

4.6

 

85th Percentile Speed

53

53

0

Table 13. Speed reduction for Missouri - Hwy 221.

  Before 1 Month Change

Mean Speed Reduction Upstream to PC

0.6

2.6

2

Mean Speed Reduction Upstream to CC

3.9

4.3

0.4

Mean Speed Reduction PC to CC

3.4

1.7

-1.7

85th Percentile Speed Reduction Upstream to PC

3

6

3

85th Percentile Speed Reduction Upstream to CC

7

8

1

85th Percentile Speed Reduction PC to CC

5

3

-2

 

Missouri (Hwy 221)

Image -  Missouri Highway 221 curve site
Graph: Missouri Highway 221 impact on mean and 85th percentile speeds for upstream (55 mile per hour speed limit), point of curvature (40 mile per hour advisory speed), and center of curve before implementation and 1 month after
Figure 47. Graph. Impact on vehicle speed - Missouri Hwy 221.

 

Missouri (Hwy 221)

Map - Location of sign for northbound traffic on Missouri Highway 221 Bar chart: Change in upstream percentile vehicle speeds on Missouri Highway 221 at 1 month Bar chart: Change in point of curvature percentile vehicle speeds on Missouri Highway 221 at 1 month Bar chart: Change in center of curvature percentile vehicle speeds on Missouri Highway 221 at 1 month
Figure 48. Map and graphs. Location and change in percentile vehicle speed - Missouri Hwy 221.

 

Washington SR 7

Table 14. Results for Washington - SR 7 at PC.

  Before 1 Month Change

ADT

1408

1413

5

Sample

763

766

Upstream Mean Speed

42.5

40.5

-2.0

Mean Speed

33.1

30.3

-2.8

Standard Deviation

4.7

4.6

 

85th Percentile Speed

33

30

-3

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.96

0.89

-7.3%

Percentage of Vehicles 10+ Over Limit

0.80

0.56

-30.0%

Percentage of Vehicles 15+ Over Limit

0.37

0.18

-51.4%

Percentage of Vehicles 20+ Over Limit

0.09

0.02

-77.8%

Sample

716

733

 

Tracking Data

Upstream Mean Speed

42.6

40.8

-1.8

Mean Speed

33.3

30.5

-2.8

Standard Deviation

4.6

4.4

85th Percentile Speed

38

35

-3

 

Table 15. Results for Washington - SR 7 at CC.

  Before 1 Month Change

ADT

1420

1444

24

Sample

750

770

Upstream Mean Speed

42.5

40.5

-2.0

Mean Speed

27.2

25.8

-1.4

Standard Deviation

2.9

3.3

 

85th Percentile Speed

30

29

-1

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.84

0.68

-19.0%

Percentage of Vehicles 10+ Over Limit

0.20

0.11

-45.0%

Percentage of Vehicles 15+ Over Limit

0.01

0.01

0.0%

Percentage of Vehicles 20+ Over Limit

0.00

0.00

0.0%

Tracking Data

Sample

716

733

 

Upstream Mean Speed

42.6

40.8

-1.8

Mean Speed

27.2

26.0

-1.2

Standard Deviation

2.8

3.1

 

85th Percentile Speed

30

29

-1

 

Table 16. Speed reduction for Washington - SR 7.

  Before 1 Month Change

Mean Speed Reduction Upstream to PC

9.3

10.3

1

Mean Speed Reduction Upstream to CC

15.4

14.8

-0.6

Mean Speed Reduction PC to CC

6.1

4.5

-1.6

85th Percentile Speed Reduction Upstream to PC

14

15.2

1.2

85th Percentile Speed Reduction Upstream to CC

20

21

1

85th Percentile Speed Reduction PC to CC

9

7

-2

 

Washington (SR 7)

Graph - Washington State Route 7 impact on mean and 85th percentile speeds for upstream (50 mile per hour speed limit), point of curvature (20 mile per hour advisory speed), and center of curve before implementation and 1 month after
Figure 49. Graph. Impact on vehicle speed - Washington SR 7.

Washington (SR 7)

Map: Location of sign for southbound traffic on Washington State Route 7 Bar chart: Change in upstream percentile vehicle speeds on Washington State Route 7 at 1 month Bar chart: Change in point of curvature percentile vehicle speeds on Washington State Route 7 at 1 month Bar chart: Change in center of curvature percentile vehicle speeds on Washington State Route 7 at 1 month
Figure 50. Map and graphs. Location and change in percentile vehicle speed - Washington SR 7.

Washington SR 9

Table 17. Results for Washington - SR 9 at PC.

  Before 1 Month Change

ADT

5533

6212

679

Sample

2702

3062

Upstream Mean Speed

46.9

48.7

1.8

Mean Speed

41

39.6

-1.4

Standard Deviation

5.0

5.0

85th Percentile Speed

46

45.0

-1

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.23

0.16

-30.4%

Percentage of Vehicles 10+ Over Limit

0.04

0.02

-50.0%

Percentage of Vehicles 15+ Over Limit

0.01

0.00

-100.0%

Percentage of Vehicles 20+ Over Limit

0.00

0.00

0.0%

Tracking Data

Sample

2598

2957

Upstream Mean Speed

47.1

48.8

1.7

Mean Speed

41.1

39.7

-1.4

Standard Deviation

4.9

4.9

85th Percentile Speed

46

44

-2

 

Table 18. Results for Washington - SR 9 at CC.

  Before 1 Month Change

ADT

5523

6227

704

Sample

2688

3081

 

Upstream Mean Speed

46.9

48.7

1.8

Mean Speed

40.2

39.3

-0.9

Standard Deviation

5.0

5.0

 

85th Percentile Speed

45

44

-1

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.19

0.14

-26.3%

Percentage of Vehicles 10+ Over Limit

0.03

0.02

-33.3%

Percentage of Vehicles 15+ Over Limit

0.00

0.00

0.0%

Percentage of Vehicles 20+ Over Limit

0.00

0.00

0.0%

Tracking Data

Sample

2598

2957

 

Upstream Mean Speed

47.1

48.8

1.7

Mean Speed

40.3

39.3

-1

Standard Deviation

5.0

4.9

 

85th Percentile Speed

45

44

-1

Table 19. Speed reduction for Washington - SR 9

  Before 1 Month Change

Mean Speed Reduction Upstream to PC

6.0

9.1

3.1

Mean Speed Reduction Upstream to CC

6.8

9.5

2.7

Mean Speed Reduction PC to CC

0.8

0.4

-0.4

85th Percentile Speed Reduction Upstream to PC

9

13

4

85th Percentile Speed Reduction Upstream to CC

10

13

3

85th Percentile Speed Reduction PC to CC

2

1

-1

 

Washington (SR 9)

Image - Washington State Route 9 curve site
Graph: Washington State Route 9 impact on mean and 85th percentile speeds for upstream (55 mile per hour speed limit), point of curvature (40 mile per hour advisory speed), and center of curve before implementation and 1 month after
Figure 51. Graph. Impact on vehicle speed - Washington SR 9

Washington (SR 9)

Map: Location of sign for southbound traffic on Washington State Route 9 Bar chart: Change in upstream percentile vehicle speeds on Washington State Route 9 at 1 month Bar chart: Change in point of curvature percentile vehicle speeds on Washington State Route 9 at 1 month Bar chart: Change in center of curvature percentile vehicle speeds on Washington State Route 9 at 1 month
Figure 52. Map and graphs. Location and change in percentile vehicle speed - Washington SR 9.

Washington SR 203

Table 20. Results for Washington - SR 203 at PC

  Before 1 Month Change

ADT

10088

10761

673

Sample

4901

5190

Upstream Mean Speed

53.8

54.2

0.4

Mean Speed

53.5

51.5

-2.0

Standard Deviation

5.0

4.5

85th Percentile Speed

58

56

-2

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.96

0.94

-2.1%

Percentage of Vehicles 10+ Over Limit

0.83

0.71

-14.5%

Percentage of Vehicles 15+ Over Limit

0.43

0.23

-46.5%

Percentage of Vehicles 20+ Over Limit

0.08

0.03

-62.5%

Tracking Data

Sample

4637

4902

Upstream Mean Speed

54.1

54.4

0.3

Mean Speed

53.6

51.6

-2

Standard Deviation

4.7

4.5

85th Percentile Speed

58

56

-2

 

Table 21. Results for Washington - SR 203 at CC.

  Before 1 Month Change

ADT

10120

10756

636

Sample

4921

5148

Upstream Mean Speed

53.8

54.2

0.4

Mean Speed

51.6

51.5

-0.1

Standard Deviation

4.6

4.6

85th Percentile Speed

56

56

0

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.94

0.94

0.0%

Percentage of Vehicles 10+ Over Limit

0.72

0.70

-2.8%

Percentage of Vehicles 15+ Over Limit

0.25

0.24

-4.0%

Percentage of Vehicles 20+ Over Limit

0.03

0.03

0.0%

Tracking Data

Sample

4637

4902

Upstream Mean Speed

54.1

54.4

0.3

Mean Speed

51.8

51.6

-0.2

Standard Deviation

4.5

4.6

85th Percentile Speed

56

56

0

 

Table 22. Speed reduction for Washington - SR 203.

  Before 1 Month Change

Mean Speed Reduction Upstream to PC

0.5

2.8

2.3

Mean Speed Reduction Upstream to CC

2.4

2.8

0.4

Mean Speed Reduction PC to CC

1.8

0

-1.8

85th Percentile Speed Reduction Upstream to PC

3

6

3

85th Percentile Speed Reduction Upstream to CC

6

7

1

85th Percentile Speed Reduction PC to CC

3

2

-1

 

Washington (SR 203)

Image: Washington State Route 203 curve site Graph: Washington State Route 203 impact on mean and 85th percentile speeds for upstream (55 mile per hour speed limit), point of curvature (no curve advisory speed), and center of curve before implementation and 1 month after
Figure 53 Graph Impact on vehicle speed - Washington SR 203.

Washington (SR 203)

Map: Location of sign for southbound traffic on Washington State Route 203 Bar chart: Change in upstream percentile vehicle speeds on Washington State Route 203 at 1 month Bar chart: Change in point of curvature percentile vehicle speeds on Washington State Route 203 at 1 month Bar chart: Change in center of curvature percentile vehicle speeds on Washington State Route 203 at 1 month
Figure 54. Map and graphs. Location and change in percentile vehicle speed - Washington SR 203.

Wisconsin Highway 20

Table 23. Results for Wisconsin - Hwy 20 at PC

  Before 1 Month Change

ADT

3583

3250

-333

Sample

1692

1556

Upstream Mean Speed

53.7

55.2

1.5

Mean Speed

39.6

37.8

-1.8

Standard Deviation

7.6

7.1

85th Percentile Speed

47

45

-2

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.77

0.70

-9.1%

Percentage of Vehicles 10+ Over Limit

0.58

0.47

-19.0%

Percentage of Vehicles 15+ Over Limit

0.27

0.16

-40.7%

Percentage of Vehicles 20+ Over Limit

0.07

0.03

-57.1%

Tracking Data

Sample

1318

1251

Upstream Mean Speed

54.1

55.7

1.6

Mean Speed

42.1

40.1

-2

Standard Deviation

5.7

5.4

85th Percentile Speed

48

45

-3

Table 24. Results for Wisconsin - Hwy 20 at CC

 

Before

1 Month

Change

ADT

3128

2823

-305

Sample

1456

1350

Upstream Mean Speed

53.7

55.2

1.5

Mean Speed

37.4

35.6

-1.8

Standard Deviation

4.8

4.6

85th Percentile Speed

42

40

-2

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.77

0.63

-18.2%

Percentage of Vehicles 10+ Over Limit

0.33

0.18

-45.5%

Percentage of Vehicles 15+ Over Limit

0.06

0.02

-66.7%

Percentage of Vehicles 20+ Over Limit

0.01

0.00

-100.0%

Tracking Data

Sample

1318

1251

Upstream Mean Speed

54.1

55.7

1.6

Mean Speed

37.8

36.1

-1.7

Standard Deviation

4.4

4.1

85th Percentile Speed

42

40

-2

Table 25. Speed reduction for Wisconsin - Hwy 20

  Before 1 Month Change

Mean Speed Reduction Upstream to PC

12.0

15.6

3.6

Mean Speed Reduction Upstream to CC

16.2

19.5

3.3

Mean Speed Reduction PC to CC

4.3

4.0

-0.3

85th Percentile Speed Reduction Upstream to PC

18

20

2

85th Percentile Speed Reduction Upstream to CC

23

25

2

85th Percentile Speed Reduction PC to CC

8

7

-1

 

Wisconsin (Hwy 20)

Image: Wisconsin Highway 20 curve site Graph: Wisconsin Highway 20 impact on mean and 85th percentile speeds for upstream (55 mile per hour speed limit), point of curvature (30 mile per hour advisory speed), and center of curve before implementation and 1 month after
Figure 55. Graph. Impact on vehicle speed - Wisconsin Hwy 20.

Wisconsin (Hwy 20)

Map: Location of sign for eastbound traffic on Wisconsin Highway 20 Bar chart: Change in upstream percentile vehicle speeds on Wisconsin Highway 20 at 1 month Bar chart: Change in point of curvature percentile vehicle speeds on Wisconsin Highway 20 at 1 month Bar chart: Change in center of curvature percentile vehicle speeds on Wisconsin Highway 20 at 1 month
Figure 56. Map and graphs. Location and change in percentile vehicle speed - Wisconsin Hwy 20.

Wisconsin Highway 67

Table 26. Results for Wisconsini - Hwy 67 at PC.

  Before 1 Month Change

ADT

3494

4018

524

Sample

1726

1992

 

Upstream Mean Speed

50.0

48.9

-1.1

Mean Speed

46.1

44.5

-1.6

Standard Deviation

5.9

6

 

85th Percentile Speed

52

51

-1

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.99

0.99

0.0%

Percentage of Vehicles 10+ Over Limit

0.97

0.94

-3.1%

Percentage of Vehicles 15+ Over Limit

0.87

0.80

-8.0%

Percentage of Vehicles 20+ Over Limit

0.65

0.51

-21.5%

Tracking Data

Sample

1668

1931

 

Upstream Mean Speed

50.0

48.9

-1.1

Mean Speed

46.1

44.5

-1.6

Standard Deviation

5.8

6.0

 

85th Percentile Speed

52

51

-1

 

Table 27. Results for Wisconsin - Hwy 67 at CC.

  Before 1 Month Change

ADT

3496

4004

508

Sample

1713

1979

 

Upstream Mean Speed

50.0

48.9

-1.1

Mean Speed

39.7

37.9

-1.8

Standard Deviation

5.0

5.0

 

85th Percentile Speed

45

43

-2

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.97

0.95

-2.1%

Percentage of Vehicles 10+ Over Limit

0.86

0.76

-11.6%

Percentage of Vehicles 15+ Over Limit

0.53

0.38

-28.3%

Percentage of Vehicles 20+ Over Limit

0.15

0.08

-46.7%

Tracking Data

Sample

1668

1931

 

Upstream Mean Speed

50.0

48.9

-1.1

Mean Speed

39.7

37.9

-1.8

Standard Deviation

5.0

5.0

 

85th Percentile Speed

45

43

-2

Table 28. Speed Reduction for Wisconsin - Hwy 67.

  Before 1 Month Change

Mean Speed Reduction Upstream to PC

3.9

4.40

0.5

Mean Speed Reduction Upstream to CC

10.2

11.0

0.8

Mean Speed Reduction PC to CC

6.4

6.6

0.2

85th Percentile Speed Reduction Upstream to PC

11

13

2

85th Percentile Speed Reduction Upstream to CC

19

20

1

85th Percentile Speed Reduction PC to CC

9

9

0

 

Wisconsin (Hwy 67)

Image: Wisconsin Highway 67 curve site Graph: Wisconsin Highway 67 impact on mean and 85th percentile speeds for upstream (55 mile per hour speed limit), point of curvature (25 mile per hour advisory speed), and center of curve before implementation and 1 month after
Figure 57. Graph. Impact on vehicle speed - Wisconsin Hwy 67

Wisconsin (Hwy 67)

Map: Location of sign for southbound traffic on Wisconsin Highway 67 Bar chart: Change in upstream percentile vehicle speeds on Wisconsin Highway 67 at 1 month Bar chart: Change in point of curvature percentile vehicle speeds on Wisconsin Highway 67 at 1 month Bar chart: Change in center of curvature percentile vehicle speeds on Wisconsin Highway 67 at 1 month
Figure 58. Map and graphs. Location and change in percentile vehicle speed - Wisconsin

Wisconsin Highway 213

Table 29. Results for Wisconsin - Hwy 213 at PC.

  Before 1 Month Change

ADT

2369

2249

-120

Sample

1156

1119

 

Upstream Mean Speed

58.8

59.8

1.0

Mean Speed

55.3

54.6

-0.7

Standard Deviation

7

6.6

 

85th Percentile Speed

61

61

0

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.63

0.57

-9.5%

Percentage of Vehicles 10+ Over Limit

0.28

0.21

-25.0%

Percentage of Vehicles 15+ Over Limit

0.03

0.03

0.0%

Percentage of Vehicles 20+ Over Limit

0.00

0.00

0.0%

Tracking Data

Sample

1134

1098

 

Upstream Mean Speed

58.9

59.9

1

Mean Speed

55.5

54.8

-0.7

Standard Deviation

6.5

6.2

 

85th Percentile Speed

61

61

0

Table 30. Results for Wisconsin-Hwy 213 at CC.

  Before 1 Month Change

ADT

2552

2428

-124

Sample

1220

1193

 

Upstream Mean Speed

58.8

59.8

1.0

Mean Speed

53.2

52.2

-1.0

Standard Deviation

9.7

9.8

 

85th Percentile Speed

61

60

-1

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.59

0.52

-11.9%

Percentage of Vehicles 10+ Over Limit

0.25

0.20

-20.0%

Percentage of Vehicles 15+ Over Limit

0.02

0.03

50.0%

Percentage of Vehicles 20+ Over Limit

0.00

0.00

0.0%

Tracking Data

Sample

1134

1098

 

Upstream Mean Speed

58.9

59.9

1

Mean Speed

54.7

54.0

-0.7

Standard Deviation

7.7

7.5

 

85th Percentile Speed

61

61

0

Table 31. Speed reduction for Wisconsin - Hwy 213.

  Before 1 Month Change

Mean Speed Reduction Upstream to PC

3.4

5.1

1.7

Mean Speed Reduction Upstream to CC

4.2

5.9

1.7

Mean Speed Reduction PC to CC

0.8

0.8

0

85th Percentile Speed Reduction Upstream to PC

9

10

1

85th Percentile Speed Reduction Upstream to CC

10

11.5

1.5

85th Percentile Speed Reduction PC to CC

2

2

0

 

Wisconsin (Hwy 213)

Image - Wisconsin Highway 213 curve site
Graph: Wisconsin Highway 213 impact on mean and 85th percentile speeds for upstream (55 mile per hour speed limit), point of curvature (50 mile per hour advisory speed), and center of curve before implementation and 1 month after
Figure 59. Graph. Impact on vehicle speed - Wisconsin Hwy 213.

Wisconsin (Hwy 213)

Map: Location of sign for eastbound traffic on Wisconsin Highway 213 Bar chart: Change in upstream percentile vehicle speeds on Wisconsin Highway 213 at 1 month Bar chart: Change in point of curvature percentile vehicle speeds on Wisconsin Highway 213 at 1 month Bar chart: Change in center of curvature percentile vehicle speeds on Wisconsin Highway 213 at 1 month
Figure 60. Map and graphs. Location and change in percentile vehicle speed - Wisconsin Hwy 213.

Texas FM 109

Table 32. Results for Texas - FM 109 at PC.

  Before 1 Month Change

ADT

2187

2031

-156

Sample

1036

954

 

Upstream Mean Speed

58.2

59.6

1.4

Mean Speed

46.6

45.8

-0.8

Standard Deviation

5.7

5.4

 

85th Percentile Speed

52

51

-1

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.92

0.90

-2.2%

Percentage of Vehicles 10+ Over Limit

0.68

0.62

-8.8%

Percentage of Vehicles 15+ Over Limit

0.30

0.23

-23.3%

Percentage of Vehicles 20+ Over Limit

0.07

0.04

0.0%

Table 33. Results for Texas - FM 109 at CC.

  Before 1 Month Change

ADT

2129

 1991

-138

Sample

1017

 938

 

Upstream Mean Speed

58.2

59.6

1.4

Mean Speed

45.2

 43.8

-1.4

Standard Deviation

5.2

 4.7

 

85th Percentile Speed

50

 48

-2

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.90

 0.85

-5.7%

Percentage of Vehicles 10+ Over Limit

0.60

 0.43

-27.7%

Percentage of Vehicles 15+ Over Limit

0.18

 0.09

-51.4%

Percentage of Vehicles 20+ Over Limit

0.02

 0.01

0.0%

 

Texas (FM 109)

Graph: Texas FM 109 impact on mean and 85th percentile speeds for upstream (60 mile per hour speed limit), point of curvature (35 mile per hour advisory speed), and center of curve before implementation and 1 month after
Figure 61. Graph. Impact on vehicle speed - Texas FM 109

Texas (FM 109)

Map: Location of sign for northbound traffic on Texas FM 109 Bar chart: Change in upstream percentile vehicle speeds on Texas FM 109 at 1 month Bar chart: Change in point of curvature percentile vehicle speeds on Texas FM 109 at 1 month Bar chart: Change in center of curvature percentile vehicle speeds on Texas FM 109 at 1 month
Figure 62. Map and graphs. Location and change in percentile vehicle speed - Texas FM 109.

Texas FM 407

Table 34. Results for Texas - FM 407 at PC

  Before 1 Month Change

ADT

2480

2883

403

Sample

856

1443

 

Upstream Mean Speed

61.3

60.1

-1.2

Mean Speed

51.5

49.7

-1.8

Standard Deviation

5.6

5.3

 

85th Percentile Speed

57

55

-2

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.89

0.83

-6.7%

Percentage of Vehicles 10+ Over Limit

0.67

0.53

-20.9%

Percentage of Vehicles 15+ Over Limit

0.31

0.18

-41.9%

Percentage of Vehicles 20+ Over Limit

0.06

0.03

0.0%

*Note: Only 18 hours of data collected because of puncture in the tube

 

Table 35. Results for Texas - FM 407 at CC.

  Before 1 Month Change

ADT

2238

2885

647

Sample

579

1446

 

Upstream Mean Speed

61.3

60.1

-1.2

Mean Speed

47.3

46.2

-1.1

Standard Deviation

6.3

5.6

 

85th Percentile Speed

53

51

-2

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.73

0.67

-8.2%

Percentage of Vehicles 10+ Over Limit

0.37

0.26

-29.7%

Percentage of Vehicles 15+ Over Limit

0.10

0.04

-60.0%

Percentage of Vehicles 20+ Over Limit

0.01

0.01

0.0%

*Note: Only 16 hours of data collected because of puncture in the tube

 

Texas (FM 407)

Graph: Texas FM 407 impact on mean and 85th percentile speeds for upstream (55 mile per hour speed limit), point of curvature (40 mile per hour advisory speed), and center of curve before implementation and 1 month after
Figure 63. Graph. Impact on vehicle speed - Texas FM 407.

 

Texas (FM 407)

Map - Location of sign for eastbound traffic on Texas FM 407. Bar chart - Change in upstream percentile vehicle speeds on Texas FM 407at 1 month Bar chart: Change in point of curvature percentile vehicle speeds on Texas FM 407at 1 month Bar chart: Change in center of curvature percentile vehicle speeds on Texas FM 407at 1 month
Figure 64. Map and graphs. Location and change in percentile vehicle speed - Texas FM 407.

Texas FM 530

Table 36. Results for Texas - FM 530 at PC.

  Before 1 Month Change

ADT

675

418

-257

Sample

71

200

 

Upstream Mean Speed

62.1

60.0

-2.1

Mean Speed

47.1

46.2

-0.9

Standard Deviation

9.3

6.3

 

85th Percentile Speed

55

53

-2

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.86

0.88

2.3%

Percentage of Vehicles 10+ Over Limit

0.77

0.62

-19.5%

Percentage of Vehicles 15+ Over Limit

0.38

0.33

-13.2%

Percentage of Vehicles 20+ Over Limit

0.20

0.09

0.0%

*Note: The “before” count had many unknown counts, leading to fewer counts for the 24-hour period

 

Table 37. Results for Texas - FM 530 at CC.

  Before 1 Month Change

ADT

488

430

-58

Sample

237

204

 

Upstream Mean Speed

62.1

60.0

-2.1

Mean Speed

43.2

41.2

-2.0

Standard Deviation

6.1

5.2

 

85th Percentile Speed

48.6

46

-2.6

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.79

0.63

-20.3%

Percentage of Vehicles 10+ Over Limit

0.44

0.28

-36.4%

Percentage of Vehicles 15+ Over Limit

0.11

0.04

-63.6%

Percentage of Vehicles 20+ Over Limit

0.02

0.00

0.0%

 

Texas (FM 530)

Graph: Texas FM 530 impact on mean and 85th percentile speeds for upstream (60 mile per hour speed limit), point of curvature (35 mile per hour advisory speed), and center of curve before implementation and 1 month after
Figure 65. Graph. Impact on vehicle speed - Texas FM 530

 

Texas (FM 530)

Map: Location of sign for westbound traffic on Texas FM 530 Bar chart: Change in upstream percentile vehicle speeds on Texas FM 530 at 1 month Bar chart: Change in point of curvature percentile vehicle speeds on Texas FM 530 at 1 month. Bar chart: Change in center of curvature percentile vehicle speeds on Texas FM 530 at 1 month
Figure 66. Map and graphs. Location and change in percentile vehicle speed - Texas FM 530.

Texas FM 1148

Table 38. Results for Texas - FM 1148 at PC.

  Before 1 Month Change

ADT

3549

3742

193

Sample

1746

1832

 

Upstream Mean Speed

59.3

58.9

-0.4

Mean Speed

51.9

49.5

-2.4

Standard Deviation

5

4.8

 

85th Percentile Speed

57

54

-3

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.94

0.86

-8.5%

Percentage of Vehicles 10+ Over Limit

0.70

0.51

-27.1%

Percentage of Vehicles 15+ Over Limit

0.28

0.13

-53.6%

Percentage of Vehicles 20+ Over Limit

0.06

0.02

0.0%

 

Table 39. Results for Texas - FM 1148 at CC.

  Before 1 Month Change

ADT

3538

3708

170

Sample

1748

1831

 

Upstream Mean Speed

59.3

58.9

-0.4

Mean Speed

48.5

48.4

-0.1

Standard Deviation

4.5

4.9

 

85th Percentile Speed

53

53

0

fraction of vehicles exceeding advisory speed

Percentage of Vehicles 5+ Over Limit

0.83

0.79

-4.8%

Percentage of Vehicles 10+ Over Limit

0.40

0.41

2.5%

Percentage of Vehicles 15+ Over Limit

0.08

0.08

0.0%

Percentage of Vehicles 20+ Over Limit

0.01

0.01

0.0%

 

Texas (FM 1148)

Graph: Texas FM 1148 impact on mean and 85th percentile speeds for upstream (55 mile per hour speed limit), point of curvature (40 mile per hour advisory speed), and center of curve before implementation and 1 month after
Figure 67. Graph. Impact on vehicle speed - Texas FM 1148

Texas (FM 1148)

Map: Location of sign for northbound traffic on Texas FM 1148
Bar chart: Change in upstream percentile vehicle speeds on Texas FM 1148 at 1 month Bar chart: Change in point of curvature percentile vehicle speeds on Texas FM 1148 at 1 month Bar chart: Change in center of curvature percentile vehicle speeds on Texas FM 1148 at 1 month
Figure 68. Map and graphs. Location and change in percentile vehicle speed - Texas FM 1148

Page last modified on July 17, 2013.
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