Aoi KONNO

Research on the Contraction of Route Bus Services in Depopulated Areas and the Associated Subsidy Systems

Teppei KATO

Route buses are a critical infrastructure not only for the mobility-impoverished but also for reducing private car dependency; however, many operators are currently trapped in a negative spiral of rising deficits and severe driver shortages. This study focuses on Nagaoka City from 1995 to 2025, revealing that while some routes have expanded, others face contraction due to a mismatch between actual ridership and revenue-based subsidies. A significant issue is that high student demand, though beneficial for physical occupancy, lowers the "average riding density" used for national subsidy benchmarks because of mandated fare discounts. Consequently, routes with high social value are often subjected to "density-based service cuts" without external compensation for these discounts. Model analysis of 35 routes in Nagaoka demonstrates that the necessary compensation rate, denoted as $\theta^*$, varies by route and serves as a vital benchmark for predicting future contractions. Furthermore, the analysis indicates that municipalities with smaller fiscal scales experience greater social welfare losses when providing subsidies, leading to a disparity in decision-making between national and local authorities. These results suggest that to sustain local bus networks, it is essential to establish a system that compensates for fare discounts and mitigates the impact of municipal fiscal disparities, thereby improving driver treatment and ensuring service stability.