Briefle words · Data & charts
Time axis
Also called proportional spacing
A horizontal axis where distance is proportional to elapsed time, rather than one slot per data point, so slopes reflect real rates of change.
Say it to an AI
Line chart of bike commute share for the survey waves 2019, 2020, 2024 and 2026 with a takeaway title. Use a time axis (proportional spacing), not a categorical axis: place points by year so the 2020 to 2024 gap is four times wider than 2019 to 2020, with each value labelled.
How an expert would brief the stronger version of “Cycling share over years”.
See it
Try it as a puzzle →Trend chart on a city's open-data transport page, built from a survey that skipped three years.
Why: In B the 2020 and 2024 points are four times farther apart than 2019 and 2020; in A all neighbours are the same distance apart.
Related words
Room 3 · Axes & scales
Learn “Time axis” in a five-minute lesson