Some charts try to make you an April fool all the time (or why 3d pie charts are evil)

Recently I saw a big screaming ad that said “the chartbuster rules”. Of course, I know that chartbusters rule. Not just because I was one of them 🙂

So I got curious and read on. And I realized the ‘chartbuster’ is actually a car, not some cool, spreadsheet waving, goatee sporting dude like Jon Peltier. What a bummer!

And then to my horror of horrors, I saw the exploding 3d pie chart, with reflection effects & glossy colors. And the sole purpose of the chart is to create an impression that Verna sells better than any car in India.

First take a look at the chart:

Now for criticism

Obviously there is no denying that Verna sells better. If you look at the number of units sold, Verna’s 56,486 is better than any other numbers.

But is that the impression the chart gives?

If you just look at slicers and colors (which is what you would do), you feel that Verna has 40-45% market share.

What is the reality? It is 31.4%

Why such a distortion in our perception?!?

This is because, the ad uses a mildly evil magic called 3d pie charts, to distort what you perceive.

Then the chart maker sprinkled this 3d pie chart with assorted poisonous sprouts called as ‘customized rotation of slices’ and ‘exploding the pie for Verna, to make it look big’.

Now, the chart means one thing, but says another. Its like my wife when she wants new shoes.

Can chart rotation impact your perception – here is the proof!

Now, you might be wondering, “Oh Chandoo, come on my man. Why would I be dumb enough to fall for this.”.

So I have made a proof. I made a similar 3d pie chart from these exact numbers. Then I rotated it from 0 to 360 degrees. And you can see how the slices of pie play with your eye.

So what is a better alternative for this chart?

In this case a column chart is better. It clearly shows the leadership position of Verna without resorting to sneaky tricks.

What more, you can format the column chart so that it has all the bling! (not that I recommend such over formatting)

PS: A newer version of this ad features column chart, albeit with convoluted staircase representation.

What do you think about rotated, exploded 3d pie charts

The only time I want to rotate a pie is when it is too big and the portion I want to eat is on the other side.

What about you? do you make 3d pies? Are they tasty or sneaky (like the Verna pie)?

Share your thoughts using comments.

Take our 3d pie pledge

As a fun exercise, why don’t you take our 3d Pie pledge. Here it is.

I promise to never make a 3d pie chart. If I ever see one, I promise to not rotate or explode it. I also promise to create alternative charts (usually column, bar, line or scatter plots) so that my audience can see the truth better.

And oh yeah, I promise to bake & eat pies whenever possible. Apart from cakes, pastries, ice creams, biscuits and other assorted fun foods that is.

signed…

Go ahead and take the pledge

PS: Chartbuster series of articles & more charting principles.