Workload equity in vehicle routing: The impact of alternative workload resources

•The cost of balance depends primarily on the workload resource, and less on the equity function.•More complex equity functions, and balancing tour lengths, yield the most compromise solutions.•For the same workload resource, most solutions can be found with multiple equity functions.•Solutions optimized for one resource are usually poorly balanced in terms of another.•Solutions with similar cost and balance values tend to share many common arcs.