Delays caused by what TfL calls “customers and public action” include commuters taking ill, items dropped on the track and people jumping in front of trains. Documents published by TfL reveal that more than 20 people a year kill themselves on the Underground.
Transport for London measures delays in what it calls Lost Customer Hours (LCH). These are calculated by multiplying the delays in minutes by the number of passengers. TfL records all delays over 2 minutes. It uses the financial year from April to March and splits the year in 13 equal periods for performance measurement.
Data in the London Underground Performance Almanac for the last full year shows there was an average of 129,010 Lost Customer Hours per period on the Victoria Line. This makes it one of the better performers.
The Victoria Line was the first to introduce automated operations where the train is controlled by computer overseen by a driver. These types of automated systems are also in use on the Central and Jubilee lines but only on the Victoria Line do they feature as a significant cause of Lost Customer Hours. They were blamed for 13% of the delays last year on this line.