The pie chart faces a tremendous amount of criticism for attempts to show part to the whole relations. Of course – it is easily the single most misused chart! However more and more data visualizations practitioners are writing articles to defend it with Robert Kosara being the most thorough and methodical in my opinion.

Here I will offer an alternative which is something like a mix of square pie chart, marimekko and packed bars. Let me introduce the Cake Chart:

It’s features:

• Always a regular square, total area = 100%.
• Each segment is a bar for easy comparison, but its area represents the percentage.
• The height of the chart is distributed evenly among bars.
• Only the selected number of largest categories are shown separately.
• All other categories are aggregated into the irregular steppy gray area.
• If there are 5 categories shown separately, then the largest cannot be larger than 100% / 5 = 20%. For X categories to be shown – the maximum value cannot be larger than 100% / X.

Weaknesses:

• Aggregated other categories are difficult to compare to bars.
• There are limitations how long the longest bar can be without destroying the squariness of the square.
• Square is not as intuitive to be 100% as circle.

Strengths:

• Bars are super easy to compare.
• It’s still a regular shape.

It’s quite obvious how to make it – make the panel square, make its background grey. However, making the Others category selectable in Tableau is a challenge and here is the result: