Countdown accuracy is how close the countdown was to the timetable.

The number the site used to call on time

This is the old headline, renamed and kept for comparison. It says how close the countdown was to the timetable. It does not say whether the bus came.

Why it reads higher

Cancelled trips and trips that never came have no prediction, so this number never saw them. That is why it reads higher than observed on time.

Where it comes from

It is built from the last prediction before each stop. It is shown beside observed on time during the one month side by side.

Why the time we show leans early

Times we show are the earliest the bus is likely to arrive, so you are at the stop before it is.

A bus that often runs late never pushes the time later.

How often the bus came before the time we showed will be measured once we have enough history.

Where the numbers come from

• OC Transpo trip updates (predictions)
• Published timetables, dated

Method version and change log

A published month never changes. If a method is revised, past months keep the method they were worked out with.

• Version 1 · October 25, 2026. Renamed. This is the number the site used to call on time. It is now called countdown accuracy and sits beside observed on time during the one month side by side.