A pie graph would be used for percents (anything that adds up to 100%)
It is used for showing statistics
A pie graph is used when representing portions of a whole.
if your trying to show percentage and not change in percentage u use a pie graph
For any data that can be best expressed as percentages of a whole, a pie chart or pie graph is appropriate.
pie graph
A pie graph is useful for showing percentages. It is great for showing percentages in a survey.
When dealing with percentages %
Line graph
A pie graph is more effective that other types of graphs for showing shares of a total.
In statistics when comparing data
On a pie graph
A pie graph does not have an axis.
I use a bar graph to represent my favorite pies, and a pie graph to represent my favorite bars.