Pizza Pie
by Jon Peltier
Thursday, February 19th, 2009
Peltier Technical Services, Inc., Copyright © 2010.
Licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported License.
A reader wanted a pie chart to help track weight loss. She acknowledged that pie charts aren’t the best way to show data, and in fact a timeline shows progress over time well.
But there is a certain charm in, say, a pizza pie chart, which shows the current progress by eating away at the pizza. To compare two values, I pie chart is not totally terrible, so I’ve put together a simple protocol here.
The data is simple. Cell B1 contains the weight loss goal, cell B2 holds the current weight lost, and cell B3 has a formula that shows the difference, =B1-B2.
Select A2:B3 and create a pie chart. It looks like this. For illustration purposes I’ve shaded the plot area of this chart light yellow, and the chart area light gray. We will use a special fill for the plot area in a moment.
First, remove the colored fills from the chart. The two wedges should have no fill at all. I’ve left black borders on the chart, or it would vanish completely.
Now find a nice picture of a pizza pie (or a chocolate cake or lemon meringue pie). This picture came via Google Images from Taste Test: Pizza Slimdown in Chicago Magazine, who judged this beauty from Spacca Napoli to be the best Margherita pizza in Chicago.
Right click on the plot area (not the chart area or either of the pie sections), choose Format, and where appropriate for your version of Excel, use the picture as the fill pattern for the plot area. In Excel 2003 and earlier, go to the Patterns tab of the Format Plot Area dialog, click the Fill Effects button at the bottom of the Area section, select the Picture tab, click on the Select Picture button, and browse to your image.
The pie fills up the whole image. Add labels to the center of the pie wedges, using a white background instead of transparent, so it shows up among the pizza toppings, and change the fill of the Already Loat segment to a solid color (white in this case).
You may even want to remove the black borders.
As you lose more weight and change the value in cell B2, the “eaten” portion of the pie increases in size.
You could probably use an image editing program to get rid of the very light gray packground in the original picture. For this demonstration I left it unchanged.
Related Posts:
- Why You Should Use PNG and not JPEG
- Split Data Range into Multiple Chart Series without VBA
- Image File Type Comparison of Exported Charts
- Display One Chart Dynamically and Interactively
- Box and Whisker Chart Median Options
- Comparison of Search Share, September and October 2009
- LOESS Smoothing in Excel
- Climate Change Survey Results
- Stacked Area Chart Challenge
- Draw an Axis With Tick Marks But No Line
Posted: Thursday, February 19th, 2009 under General.
Comments: 10
Comments
Comment from Glen Turpin
Time: Thursday, February 19, 2009, 9:13 am
I used this kind of pie chart in a presentation about restaurant loyalty marketing. I wanted to show what percentage of the market has loyalty programs, and free desserts are often used as rewards in such programs, so a literal pie chart seemed appropriate. (Mine was apple.)
I can only think of limited uses for this, but it can be a lighthearted way to show a simple relationship between two values. A playful chart can be a welcome break in a chart-heavy presentation, as long as it’s done tastefully (sorry for the pun) and doesn’t obscure the meaning of the data.
Comment from Andy Pope
Time: Thursday, February 19, 2009, 11:05 am
So the more pizza you eat the thinner you get, cool :)
This diet sounds even better than JW’s patented eHAM® diet.
Comment from Jon Peltier
Time: Thursday, February 19, 2009, 11:14 am
Andy -
It’s virtual pizza. Eat all you want, guilt-free.
Comment from Angie
Time: Thursday, February 19, 2009, 12:38 pm
Wow, you rock!! I’d share my pizza with you any day. Thank you so much. A.
Comment from teylyn
Time: Thursday, February 19, 2009, 4:02 pm
@Andy: It’s more like: you can eat this much pizza if you want to maintain your current weight. So, the thinner you get, the less pizza you’re allowed. ;-)
Comment from JP
Time: Thursday, February 19, 2009, 7:17 pm
Wouldn’t you want a legend next to the pie, showing the totals for each section? My first thought when I looked at it was that the pie was 100%, and someone was trying to starve to death :)
Comment from Gabriela Cerra
Time: Friday, February 20, 2009, 3:09 pm
I would do a salad pie, the more you eat the more thinner you get.
For a pizza, the slice of pizza will get bigger the more weight you lose, so it is the slice you are allowed to eat. If the target is met, you can go and eat a whole pizza.
Comment from Angie
Time: Friday, February 20, 2009, 4:35 pm
Hi all – it’s me, pizza girl again. I’ve got the basic concept down, but am having some problems with the final step. A couple of questions:
1. Is it possible to resize the chart to fit the picture, rather than the other way round? When I try resizing in by dragging, and then re-fill with the picture, it does everything proportionally, so I still get the same amount of deadspace within the borders of my pie chart (pizza pic a little too small – am having problems finding large enough pictures). Is there an easy way to do this or do I have to resize the pizza image, say in photoshop?
2. When I copied the chart plus pizza filling and pasted into photoshop, to get rid of the unwanted bits as you suggested above, the pizza did not travel well – I just got the pie chart with a greyscale filling. Any ideas?
Thanks guys,
Angie
Comment from Jon Peltier
Time: Friday, February 20, 2009, 5:18 pm
Angie -
I’ve never used PhotoShop, so I can’t help with #2.
To make the chart fit the pie, you have to crop the pie. This is easy enough in a program like IrfanView, which is a great free image editor. When you apply the picture as the fill, it will then fill the whole object (the whole plot area).
Comment from Hui…
Time: Friday, April 17, 2009, 11:48 am
I like Donut Charts
The hole offsets the calories of the donut – I think!
Write a comment
I welcome comments from my readers. If you have an opinion on this post, if you have a question or if there is anything to add, I want to hear from you. Whether you agree or disagree, please join the discussion.
If you want to include an image in your comment, post it on your own site or on one of the many free image sharing sites, and include a link in your comment. I'll download your image and insert the necessary html to display the image inline.
Read the PTS Blog Comment Policy.