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.

平均故障距离报告了由于列车机械问题导致的延误频次，按月份和地铁车辆类别划分。该指标是纽约地铁公司（NYCT）评估地铁车辆可靠性的主要指标，用于对比不同时间跨度和不同地铁车辆类型之间的性能表现。仅有极少数的地铁延误是由列车故障引起的。