Too many digits can distract from a useful difference and imply more certainty than the information supports. Too few can hide the change the reader is trying to understand.
Choose a display rule that fits the quantity and the purpose. Keep the underlying values available where exact detail matters, and explain any formatting that turns a value into a range or an abbreviated label.
Check totals and small values after rounding. Displayed parts may not add exactly to a displayed total, and a small positive value may appear as zero. A brief note can resolve that confusion without filling the page with unnecessary decimals.
Picture this situation.
Imagine adding rounded values that no longer match the rounded total exactly. A short explanation can preserve the reader’s understanding of the difference.
A second way to look.
A column name can hide an assumption. Check units, missing values, and the counting rule before combining observations that only appear to be alike.
- Match precision to the reader’s task.
- Keep exact values available when needed.
- Check the effect on totals and small values.
Follow a related question
Notice one preselected setting.
The quiet work of a defaultDistinguish acceptance from completion.
A queue makes room for laterKeep learning
Related background to continue exploring this subject.
NIST: statistical engineering W3C: accessibility, usability, and inclusion
