In Depth Article on Lexington Avenue Line

The nation’s most crowded subway line is jammed every morning with a crush of people waiting to board trains. Angry riders often have to let a train or two pass before they can wedge themselves inside.

It turns out that the route — the Lexington Avenue line in New York City — is regularly failing to meet its train schedule, especially during rush hour, leading to dozens of trains being canceled every day and reducing the system’s capacity by tens of thousands of riders, according to an analysis by The New York Times.

On the Lexington Avenue line, which carries the No. 4, 5 and 6 trains, just 77 of 90 scheduled trains routinely run through the busy Grand Central Station stop from 8 to 9 a.m. The rest, 14 percent of trains, are effectively canceled, at a time when the system needs them most.

Again in the evening, from 5 to 6 p.m., only 76 of 88 scheduled trains stop at the station, on average. Each canceled train accounts for roughly 1,000 passengers who could be accommodated if the system met its published schedule.
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