To test the methodology, a series of experiments were conducted using data provided by a leading
shipping carrier for the Pittsburgh area. Currently, the region is divided into 73 VRZs, compared to 64
indicated by the clustering procedure. The simulation results showed that a redesign would yield approximately
$334,360 in annual savings without any noticeable deterioration in service. In addition, when the
heuristic TSP model was solved in place of the exact model, the average gap in tour duration increased by
only 0.16 hours and 0.2 hours for the cases of 73 clusters and 64 clusters, respectively, indicating a small
upward bias. However, runtimes decreased by almost 70%.