Make all text horizontal, practical and readable Aim to show trends , not detail Use a consistent format when showing groups of graphs. If you need to show specific numbers, a table is probably best. When emphasizing something, make sure you are not distorting it. Notes Most of the time you can replace pie charts with tables in a report. When making presentations, however, pie charts may communicate your data better.
Pie charts show portions of a whole.
If you need to show multiple pies you should use a stacked bar graph instead. Be careful with 3-D effects which can distort the data. More than 6-10 bars is too many. Continuous data is where you may not have sampled at intermediate points, but you could have. For example, time is the most common x-axis on a line graph.