Guidelines
Suggest edit

Keep the footnote to essential interpretation details

For explanatory reading of a chart based on a complex prediction, use the footnote on the chart for only the source and assumptions needed to understand the display to improve trust and mitigate overloaded notes for readers checking how to interpret the result.

  • purpose:refine
  • basis:heuristic
  • quality:trust
  • lever:text-annotation
  • component:caption:use
  • communication:credibility

advice

Footnote as essentials only

Use the footnote for only the source and the assumptions needed to read the chart. For example, keep one brief caveat about what the measure does not include and a source line, and cut side explanations or extra links that are not necessary to understand the display.

reason

Why a shorter footnote works

A short footnote makes the important caveat visible without turning the note into a second article. Readers can verify the source and grasp the key assumption more quickly.

Mechanism: Concentrating the note on essential interpretation details preserves transparency while reducing distraction from information that does not change how the chart should be read.

Evidence: The post says complex predictions hide assumptions and inputs, values linking to the data source for transparency, and then recommends cutting the footnote down to the basics needed to understand the map in front of the reader (Mintzer-Sweeney, 2024).

context

Use when the note is carrying too much background detail

  • User Goal: Preserve transparency while keeping the chart readable.
  • Data: The chart shows a forecast or other assumption-heavy result.
  • Chart Setting: The chart includes a source link, and the footnote currently contains multiple explanatory details.
  • Success Criterion: A reader can quickly identify the source and the key caveat that affects interpretation.

exceptions

Do not use when the missing details are necessary to interpret the chart

Break it when: The chart has no source link, or the details you plan to cut are necessary to understand the display. Why: The source shortens the footnote only because transparency is already supported by a linked source and only the basics are needed on-chart.

costs

Tradeoffs of a shorter footnote

Sacrifice: You show less methodological detail inside the chart itself.
Risk: Readers can miss an important nuance if you cut a caveat that changes interpretation.
Mitigation: Keep the one caveat that materially affects reading and move the rest to the linked source.

mistakes

Common footnote failure

Mistake: Fill the footnote with ranking criteria, alternative measures, and extra references. Why it fails: Readers cannot tell which note actually matters for interpreting the encoded values.

check

Check whether the footnote is doing too much

Failure Sign: The footnote mixes many concepts instead of surfacing one key caveat and the source.
Quick Check: Read each clause and ask whether a reader needs it either to understand the current chart or to verify the source.
Stronger Test: After one read, a reviewer should be able to name the source and the main interpretive caveat.

fix

Fix the footnote

  • Keep a source line in the footnote.
  • Keep only the caveat that changes how readers should interpret the values.
  • Remove side explanations and extra links that are not needed to understand the chart.

References

Mintzer-Sweeney, R. (2024). Fix my chart \textraquo Using text elements. https://www.datawrapper.de/blog/fix-my-chart-text-elements