**3. Results**

#### *3.1. Descriptive Statistics*

A sample size of 9135 speed cases was achieved across the survey periods of before, after, and two years after, with similar proportions recorded under each scenario. The recordings were found to approximate a normal distribution with no significant skewness or kurtosis by visual check. There was some evidence to suggest that the distributions could be slightly bimodal, which is likely to be due to the different speed limits between cars and heavy goods vehicles. However, as individual vehicle-type data had not been collected during the speed surveys, it was not possible to refine the data any further. On this basis, the datasets were retained for further analysis unchanged. The descriptive statistics for the total number of cases under the three scenarios are shown in Table 1.

**Table 1.** Descriptive statistics by scenario and light conditions for route.

