Briefle words · Data & charts
Categorical axis
An axis that treats each label as an unordered or evenly spaced category, which is wrong for dates with uneven gaps.
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: A spreads 2019, 2020, 2024 and 2026 at equal intervals as if they were four product names.
Related words
Room 3 · Axes & scales
Learn “Categorical axis” in a five-minute lesson