Separate added context from the plot area
For explanatory reading of charts with simple core data plus extra background, prefer text hierarchy around the chart to improve readability and address competition between main and secondary information for readers who scan first and read details later.
- purpose:refine
- basis:heuristic
- quality:readability
- lever:text-annotation
- communication:context
- polish:hierarchy
advice
Move secondary context away from the plot
Separate added context from the chart’s core restatement. For example, keep interpretation-shaping background in the subtitle and move wait-until-later details to a footnote instead of letting both compete inside or right next to the plot.
reason
Why text hierarchy helps
Not all chart text needs the same proximity to the marks. When supporting facts are placed by importance, the chart can lead with its main message while still preserving extra context for later reading.
Mechanism: Subtitle placement keeps context that should shape interpretation visible early, while footnote placement holds details that readers can pick up after they understand the main chart.
Evidence: The post recommends distinguishing restatements of the core data from added information, then moving the added information farther away—into the subtitle if it should still influence interpretation, or into the footnote if it can wait until later (Mintzer-Sweeney, 2024).
context
Use when some text is supportive rather than core
- User Goal: Preserve useful background without crowding a simple main message.
- Data: Some facts discussed near the chart are not directly encoded in the marks.
- Chart Setting: The chart includes surrounding text areas such as a subtitle and footnote.
- Audience: Readers are expected to scan the main message first and pick up extra context second.
- Success Criterion: The main message stays immediate, and supporting information remains available without competing for first attention.
exceptions
Do not use for core restatements
Break it when: The text is a direct restatement of the chart’s main result. Why: That text should be moved closer to the marks as an on-chart annotation instead of being pushed outward.
costs
What this hierarchy trades off
Sacrifice: Supporting facts become less prominent than the main takeaway. Risk: If interpretation-setting context is pushed too far away, readers may miss it before reading the chart. Mitigation: Keep interpretation-setting context in the subtitle, and reserve the footnote for information that can wait.
mistakes
Common hierarchy failure
Mistake: Keep secondary facts in the same visual zone as the chart’s main summary. Why it fails: Added context and the core message compete for attention, so the simple message no longer leads.
check
How to review the text hierarchy
Failure Sign: Plot-adjacent text mixes the main takeaway with side facts and later-reading details. Quick Check: Mark each text item as either a core restatement or added information. If added information still sits in the plot area or next to the main annotation, the hierarchy is off. Stronger Test: Check whether a reader can understand the main message before reading the last supporting note.
fix
Edits to make
- Keep only core-data restatements in or on the chart.
- Move interpretation-shaping background into the subtitle.
- Move details that can wait until later into the footnote.