MTA Subway Mean Distance Between Failures: Beginning 2015

Mean Distance Between Failures reports how frequently train mechanical problems cause delays by month and subway car class. It is the main indicator for subway car reliability used at NYCT and is used to compare performance over time and across different subway car types. Only a small proportion of subway delays are due to malfunctioning trains.

故障平均距离（Mean Distance Between Failures）旨在报告由列车机械故障导致的延误发生频率，并按月份及地铁车厢类别进行划分。该指标是纽约地铁公司（NYCT）评估地铁车厢可靠性的主要参考，并用于对比不同地铁车厢类型随时间的变化性能。地铁延误中仅有小部分是由于列车故障所致。