Pies fail to deliver
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Failed university education

016_017_THE_ranksThe Times Higher Education magazine fancied itself an arbiter of good universities and yet they appeared not to have heard of Tufte, or know why we should not use 3-D pie charts, ever.

Reader Cedric K. sent in this chart, with a note of dismay. Quick, which is most important: the pink, the blue or the green?


Something like the stacked bar chart shown below delivers the information more effectively. The section showing sub-categories can be omitted.


If, in fact, it is crucial for the readers to know each weight to the second decimal, then why not just print a data table? The beauty of just using a data table is that it can accommodate long text strings, which are needed in this case to explain clearly what the subcategories actually mean.

If one wants bells and whistles, one can add little bars to the right of the proportions to visualize the weights.




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Naomi B. Robbins

Nice job. However, both the pie chart legend and the table could be improved by lining up the decimal points so that the weights were easier to add. Of course, you already did the most important addition for the readers. Also, the weights would be easier to read if they were not cluttered by so many percent signs; I'd prefer the % in the column label or the first row only.


In tables I've taken to eliminating vertical borders and grid lines altogether. With aligned text and numbers they turn out to be redundant, or to actively inhibit reading the columns properly.

(when I do this, I also align the labels on the top in whatever way the data is aligned-- in other words left aligned labels for text, right aligned labels for numbers, even though the label isn't a number)


Let's just have a moratorium on 3D pie chart posts, huh?


John: Huh? When was the last time I posted about a 3D pie chart?


Naomi and Derek: Is there an easy way to do this right alignment in Excel? I don't want to give up the right indent though. I need it to be aligned on the right with white space between the % and the column border.

Tom West

Derek: "In tables I've taken to eliminating vertical borders and grid lines altogether"
I've gone the opposyite route - it's horizontal lines which are redundent. Our eyes are good at tracking across horizontally, from years of reading stuff.


Kaiser, I don't have the border, so that's not a problem for me. But if you want white space between the right hand edge of a cell and the text and number alignments, and you don't want to use right align, then a custom number format that uses the underscore will do it. Underscore creates a white space the size of whatever character comes immediately after the underscore, so


will produce a percent format with a space the size of a capital M on the right.

@_M will do the same for text, and I think you can combine the two into one:


Obviously you don't need that fancy "none" format, but you need something for when the value is the number zero.

If you want a format that will lack the percent sign, yet line up with numbers that have the percent sign, as Naomi proposes, you can use the underscore and a percent, like so


That makes an "invisible" percentage sign.



Aug 10, but the previous post was also on pies.

Huge fan, so don't take it the wrong way, but pies and esp. 3D pies are just too easy. Fish in a barrel.


Sweet Excel tip. Thanks!

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