How often trains left this station on time.

On time means leaving no more than 5 minutes after the timetable, and never before it. At the last stop, we go by the arrival.

Why every stop? Timetables build in spare time near the end of a line. On a long line a train can run late through the middle, make it up over the last few stations and still finish on time. Checking only the end of the line would call that a good trip, but most people don't ride the whole way. If you got on or off in the middle, your train was late. Checking every stop shows where it actually was.

How we measure