One of my favourite ways to learn Tableau is to find visualisations I like and recreate them (or try to) in Tableau. I have an ever expanding ‘viz library’ which I use as inspiration.
My latest purchase ‘Infographica’ by Martin and Simon Toseland inspired my latest visualisation which I created today: ‘A penny for your thoughts‘.
I saw it and immediately wanted to replicate it. It’s beautiful, the use of colours are excellent, and most important it tells the story extremely well (and quickly). There was also the challenge that this was something I have yet to make in Tableau.
In this blog i’m going to teach you how I made these ‘circles in circles’ charts.
So here’s a copy of the data set for those that want to join in.
This data set has salary data for the UK by region. For each region we have two measures, we have the average (median) salary for that region, and we also have the median UK salary.
This is what I did…
- Drag my dimension, [Region], onto columns (or rows, It doesn’t matter!)
- Create a calculated field, simply with the value 0, and drag this calculated field onto the rows shelf.
- Drag one of my measures, [Median gross annual earnings (£) by region], onto size
- Drag the calculated field  onto rows for a second time (creating a second pane).
- Amend the marks card of this second axis by replacing our first measure [Median gross annual earnings (£) by region], with our second measure [Median gross annual earnings (£) UK-Wide], again on the size card on the marks shelf.
- Change the mark type to ‘Shape’, and if it hasn’t already, change the ‘Shape’ to the circle outline (theoretically you could just leave this as a circle and you would get a true ‘circle in circle’ chart.
- Now, for the circles to be relative to each other we must ensure they are on the same scale. To do this navigate to the size card for each of your charts, select ‘Edit Sizes…’ and make the ‘Start value in legend’ and ‘End value for range’ identical for both.
In my example I will use the range of the ‘Median gross annual earnings (£) by region’ as these start and end values, this is because the ‘Median gross annual earnings (£) UK-wide’ is the average of these values and therefor lies within that range.
This then means that the size of the gross annual earnings by region will be relative to my UK-wide data.
*An added complication…be wary of the distribution of your data and you may have to alter the start and end values accordingly*
- Make your chart a dual axis, synchronize this, and alter the colours of each chart as appropriate 🙂
You may note in my published viz that the regions are actually not in a single line. I did this by replacing the 0 values with plotted X and Y points and creating my axis from these instead. My ‘Shape mapping in Tableau’ blog may provide you with an idea on how I did this. Or you can download the workbook from my Tableau Public profile and this should also give clues.
I hope this is was a fun trick to learn! I certainly had great fun making this viz today!
Infographica is a beautiful book so I’m sure there will be a few more ideas I steal (#StealLikeAnArtist) from this book.