How to Read a Basic Chart

Every chart encodes choices: what is measured, how it is grouped, and what scale emphasizes or hides. Begin with the title and subtitle, then read axis labels before interpreting shapes.

Confirm whether the vertical axis starts at zero for bar charts comparing magnitudes. For line charts of rates, check whether the rate uses a sensible baseline population. Cross-link definitions like distribution when you see histograms or density curves.

When charts split data by category, verify that categories are mutually exclusive and that aggregations match the question—for example, monthly totals versus per-capita views.

Dual axes with unrelated units, truncated baselines without annotation, and crowded category labels often obscure meaning. Pair skeptical reading with our visualization topic hub.

Open the resource library and filter for public-sector sources, then pick an indicator page and walk this checklist aloud with a colleague.