Where this data comes from
The MTA publishes monthly performance data as open data. This page reads four of those datasets, keeps the last 59 months, and computes the rankings, trailing averages and year-over-year changes above.
- Customer Journey Time Performance — the headline number, and what the ranking is built on. The share of rider trips that finish within five minutes of the scheduled time, by line and month.
- Terminal On-Time Performance — the share of trips arriving on schedule at the terminal.
- Wait Assessment— the share of platform waits that fall within the scheduled headway, which catches the "train is running but you waited twelve minutes" problem.
- Trains Delayed by Cause — the six cause categories behind the delay bars above.
Known limits, stated plainly
- The MTA publishes monthly, about two months behind. The latest month here is August 2026, and it will not move until the MTA publishes the next one. Nothing on this page is real-time.
- J and Z are reported jointly. The MTA measures them as one series because they share a track and a service pattern, so both line pages show the same figures rather than an invented split.
- SIR isn't covered.The Staten Island Railway is not part of the subway metrics datasets, so it gets no ranking here. We'd rather leave it out than estimate.
- The shuttles are combined. The MTA reports the three shuttle services separately; this page combines them into the single S the map shows, weighted by riders.
- Monthly averages hide bad days. A line at 85% for the month still had individual trips that were far worse, and the figure says nothing about crowding — the MTA does not publish per-car crowding data at all.
Data source: MTA open data on data.ny.gov. Snapshot generated 2026-10-05; latest published month August 2026.