Dataviz in camouflage

This subway timetable in Tokyo caught my eye:

It lists the departure times of all trains going toward Shibuya on Saturdays and holidays.

It's a "stem and leaf" plot.

The stem-and-leaf plot is a crude histogram. In this version, the stem is the hour of the day (24-hour clock) and the leaf is the minute (between 0 and 59). The longer the leaf, the higher the frequency of trains.

We can see that there isn't one peak but rather a plateau between hours 9 and 18.

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Contrast this with the weekday schedule in blue:

We can clearly see two rush hours, one peak at hour 8 and a second one at hours 17-18.

Love seeing dataviz in camouflage!