Module 03 Summary

What this module established

Bars encode length and must start at zero; lines encode position and may be truncated with a labelled axis. The default in most tools is truncated, so the misleading chart is the one you get by not deciding.

Carry forward

• Every label needs the measure, the unit, and the scope and period. Charts travel without their surrounding document.
• Log axes turn equal distances into equal ratios. An unlabelled log axis understates growth to any reader who does not check.
• One annotation carries the takeaway. Annotation works by contrast, so a dozen carry none.

Before moving on

Move on when every bar chart starts at zero, every label is self-describing, and a screenshotted chart still explains itself.

Mark complete