To effectively convey information from data, a table must accentuate the important features in the data (signal) and minimise the impact of other distractions (noise). This noise may be unimportant aspects of the data (data noise) or unnecessary ink used to draw it and a table should be formatted to avoid both.

Avoiding noise

Use white space and grouping to minimise the number of lines and never use gridlines to box all values.

Usually round values to 2 or 3 significant digits.

Formatting to accentuate the signal

Consider swapping rows and columns to make the most meaningful comparisons down columns.

Avoid alphabetic ordering of rows or columns — there is usually a more meaningful way to order them.