Almost fare free: Impact of a cheap public transport ticket on mobility patterns and train delays
Journal of Public Economics · 2026 · Mario Liebensteiner、Jakob Losert、Sarah Necker、Florian Neumeier、Jörg Paetzold、Sebastian Wichert
中文摘要
2022年6月至8月，德国暂时将全国范围内不限次数乘坐的地方和区域公共交通月票价格降至每月9欧元。我们研究了这一“9欧元票”引发的出行行为变化及铁路拥堵效应。我们采用双重差分和事件研究设计，分析了来自移动网络设备的出行数据、道路监测站的行政交通流量数据以及列车到达数据。我们发现铁路出行大幅增加，而对汽车出行的替代较为有限。列车出行量增加约35%，汽车交通量下降1%—5%，其中通勤时段的交通降幅最小，周末休闲出行及前往旅游目的地的铁路出行增幅最大。此外，列车需求激增通过加剧列车延误显著恶化了服务质量，这种影响甚至外溢至长途列车。福利分析表明，该政策主要发挥了生活成本转移支付的作用，减排收益有限，意味着政府隐含的二氧化碳减排成本较高。总体而言，我们的研究结果表明，大幅折价、全国通用的“任意通行”车票能够显著增加铁路出行，但在没有配套运力扩张的情况下实施，其带来的汽车向铁路的替代作用有限，并会损害服务可靠性。
Abstract
During June–August 2022, Germany temporarily reduced the fare of unlimited local and regional public transport nationwide to €9 per month. We study changes in mobility behavior and rail congestion effects induced by this 9-Euro Ticket. We employ difference-in-differences and event-study designs to analyze data from mobile-network devices, administrative traffic counts from road monitoring stations, and train arrival data. We find a strong increase in rail travel with modest substitution away from cars. Train trips rise by around 35%, while car traffic falls by 1–5%, with the smallest traffic reductions during commuting times and the largest increases in rail travel for leisure purposes on weekends and to touristic destinations. Moreover, the train demand surge materially worsens service quality via elevated train delays, which even spill over to long-distance trains. A welfare analysis suggests that the policy mostly acted as a cost-of-living transfer with limited emissions benefits, implying high implicit CO2 government abatement costs. Overall, our findings indicate that deeply discounted, nationwide “go-anywhere” tickets can substantially increase railway travel, yet generate limited car-to-rail substitution and strain service reliability when implemented without accompanying capacity extensions.