Sensitivity Analysis of Unit Transportation Costs for Trucks and Buses: A Multi-Source Kuwait Case Study

Accurate unit transportation cost estimates are important for pricing, budgeting, and fleet planning, but conclusions based on a single representative vehicle may be misleading when operating conditions vary across fleets, routes, operators, and years. This study develops a multi-source Kuwait framework that combines deterministic vehicle-level sensitivity analysis with independent truck, route, operator, and fleet evidence. One-at-a-time perturbations, sensitivity-index ranking, local elasticity, factorial stress tests, and fuel-price scenarios are applied to published freight-truck and passenger-bus cost cases. The principal contribution is a cross-resolution framework that links equation-level cost sensitivity with independently observed operational heterogeneity while preserving the analytical resolution of each dataset and avoiding inappropriate pooling of incompatible sources. In the vehicle-level sensitivity core, annual kilometers is the leading truck parameter (SI = 16.54%), followed by maintenance cost (6.18%) and driver/worker salary (5.67%), whereas bus occupancy rate (20.79%) and annual kilometers (16.45%) are dominant. As independent contextual evidence, historical Kuwait truck observations show mean transported loads of 2.0–5.0 t/truck, while KPTC route offered-capacity utilization ranges from 13.3% to 99.7%. The results show that productive activity and utilization strongly influence unit transportation cost, but their effects are context dependent. The framework therefore improves the practical interpretation and transferability of deterministic vehicle-level sensitivity results without overstating cross-source validation.