# Let’s build a Marrimeko Chart!

Sean set the challenge this week and went retro, revisiting a challenge from 2017 originally set by Emma Whyte to build a Marrimeko chart.

Hang on… a what chart? Marrimeko…???

A good place to understand what a Marrimeko chart actually is, is this blog post by Tableau Visionary & Ambassador, Jonathan Drummey. This leads onto this post which explains the steps to help build.

The main concept of this type of chart is to show part-to-whole relationships across two variables at once.  In the above for each job title, we have a split vertically based on proportion by gender; but the proportion of people with each job title is also being represented horizontally by the width of the ‘bars’. Both the x and the y axis are up to 100%.

I was actually around when the original challenge was set, so have my solution from then already on my Tableau Public profile. But it was a long time ago, with an older version of Tableau, so I built this from scratch (using the referenced blogs as a quick refresher). This blog will take you through the steps I took (which actually didn’t end up that different from the last time).

The data

The data set isn’t very large and contains all the information we will need, but not quite in the structure we might expect

The Sub-Type = Total field contains the % we will need to define how the width of the bars should be split (all the Total values add up to 100% or just about).

Whereas the combination of the Sub Types of Male and Female define how the height of the bars should be split (Male + Female = 100% for each Job Type).

So when we come to build, we ideally want to ‘filter out’ the Sub-Type = Total field, but we still need to retain this information to build the viz.

We need to get the % values associated to each Total row to be reflected against the Male/Female rows.

We’ll create an LoD for this

Job Type Percentage

{FIXED [Job Type]: SUM(IF [Sub-Type] = ‘Total’ THEN [Percentage]END )}

format this to % with 0 dp

If we pop the data out into a tabular format as below and add Sub-Type to the Filter shelf so it excludes the Total row, we can see we have essentially transposed the values which were stored against the Total row into it’s own column.

Building the Marrimeko chart

As stated above, the Job Type Percentage field defines the width of the bars we’ll be displaying. But before we can get to the point, we also need to define where on the x-axis each mark should be positioned. This too is based on Job Type Percentage, but is the cumulative value.

On a new sheet add Job Type to Rows, Filter by Sub-Type to exclude Total, and add Job Type Percentage to text. Sort by Job Type Percentage descending.

Now add a Running Total Quick Table Calculation to the Job Type Percentage field, and the cumulative values will display.

It is these values we need to plot on the x-axis.

Duplicate the sheet.

Edit the table calculation against the Job Type Percentage field, so that it is explicitly set to compute using Job Type. This is important to ensure the calculation is retained regardless as to where we put the pill on the canvas.

Now move this pill from the Text shelf to Columns, and change the mark type to Gantt Bar. Move Job Type from Rows to the Detail shelf. Reapply the Sort to the Job Type field so its sorting by Job Type Percentage descending

The markers for the Gantt should all be positioned at the correct position.

Now add Percentage to Rows and change the mark type to Bar.

Add Job Type Percentage to the Size shelf, then click on the shelf, and change to be Fixed and aligned Right.

Now add Sub-Type to Colour. Manually drag the values in the COlour legend to re-order (so Male is listed first) and adjust colours to suit.

Ta dah! The crux of the chart.

Now to add the ‘bells and whistles’.

The chart is labelled, but only for the Entry Job Type. We need a calculated field to manage this.

Label: Sub Type

IF [Job Type] = ‘Entry’ THEN [Sub-Type] END

Add this to the Label shelf, and set to Show Mark labels. If it doesn’t show (like it didn’t on mine), change the field to be an attribute (I need to do a dig on why this is required… I think it’s something to do with the table calcs….).

I tried to use the alignment setting of the label to set to ‘top left’, but while they would left align they wouldn’t move to the top. I manually moved them instead – simply click on the label and when the cursor changes to a cross, drag the label to the desired position.

Do this for both labels, and adjust the formatting of the label too (I set it to 12pt bold).

Remove all gridlines, axis lines, zero lines etc.

Add a 50% reference line on the y-axis. Right click on the Percentage axis ->Add Reference Line. Add a table level constant of 0.5 which is a thin dotted grey line that is almost invisible (due to the colour selected).

Hide the axes (uncheck show header).

The tooltip has a minor nuance in that it refers to ‘Women’ & Men rather than Male & Female, so we need a field for this

Gender

CASE [Sub-Type]
WHEN ‘Female’ THEN ‘Women’
WHEN ‘Male’ THEN ‘Men’
END

Labelling the axes

The final viz has labels on both the x and y axis, but these are all managed by text/image objects positioned ‘cleverly’ on the dashboard. It’s a bit of trial and error to get everything aligned as required.

To label the Job Type, I used a horizontal container, positioned beneath the chart, with several text objects, some of which had the text rotated.

The Equal Proportions and Less Equality text are both floating text objects. I saved an ‘arrow’ image from the internet and added a floating image object too.

My published viz is here.

Happy vizzin’!

Donna