I know everyone has told you not to use a pie chart. I agree. But I think we should explain why. They are usually ok if there are two to three colours and there is only one of them AND you are speaking to people who only require a broad-strokes impression of the dominance of one area. If there are multiple sections one simply cannot make out the relative proprotions of the chart and it becomes meaningless. So if you must use such a chart, I suggest you group it into three: 1-Biggest group, 2-Second biggest group, 3-All the other groups.

This will at least be readable. The other terrible, criminal (aarghh!, my eyes!) mistake to make is to use multiple pie charts with multiple colors. Most people's visual working memory is very poor, in contrast to their auditory working memory. Try closing your eyes and visualising the room around you in detail. Now try reciting a random nine digit number. You'll always have more success with the number (for all sorts of reasons). Using multiple pie charts means the viewer has to remember what the chart 2 slides ago looked like, or at the very least try and make a spatial comparison between 2 circular areas. Our brains are pretty bad at that too. If you want to compare changes across time, it is a much better idea to have TIME on at least one of your axes, with lines or blocks of color representing change. In this way a stacked bar chart can represent changing proportions much more naturally and sensibly than any pie.

In answer to the original question. No. Everybody else is being very nice. Think about it. If you could divide a pie up, and then put it back together again and have there be more than you started with, that would be a really useful party trick. There's a book about a guy who used to do stuff like that. Its name eludes me now.

• " You will eat, bye and bye, In that glorious land above the sky; Work and pray, live on hay, You'll get pie in the sky when you die" - The preacher and the slave, American folk song

I know everyone has told you not to use a pie chart. I agree. But I think we should explain why. They are usually ok if there are two to three colours and there is only one of them AND you are speaking to people who only require a broad-strokes impression of the dominance of one area. If there are multiple sections one simply cannot make out the relative proportions of the chart and it becomes meaningless. So if you must use such a chart, I suggest you group it into three: 1-Biggest group, 2-Second biggest group, 3-All the other groups.

This will at least be readable. The other terrible, criminal (aarghh!, my eyes!) mistake to make is to use multiple pie charts with multiple colors. Most people's visual working memory is very poor, in contrast to their auditory working memory. Try closing your eyes and visualising the room around you in detail. Now try reciting a random nine digit number. You'll always have more success with the number (for all sorts of reasons). Using multiple pie charts means the viewer has to remember what the chart 2 slides ago looked like, or at the very least try and make a spatial comparison between 2 circular areas. Our brains are pretty bad at that too. If you want to compare changes across time, it is a much better idea to have TIME on at least one of your axes, with lines or blocks of color representing change. In this way a stacked bar chart can represent changing proportions much more naturally and sensibly than any pie.

In answer to the original question. No. Everybody else is being very nice. Think about it. If you could divide a pie up, and then put it back together again and have there be more than you started with, that would be a really useful party trick. There's a book about a guy who used to do stuff like that. Its name eludes me now.

• " You will eat, bye and bye, In that glorious land above the sky; Work and pray, live on hay, You'll get pie in the sky when you die" - The preacher and the slave, American folk song