#IronVizLearning - Simplifying Your Date Axis

For the last 4 weeks the #Datafam has been busy! Busy creating 370 diverse and inspiring #IronViz visualisations as part of the 2020 global health and wellbeing feeder. It would be wrong of me to start an #IronViz blog post without recognising this and saying a massive congratulations to everyone who participated.

If the other 369 participants are anything like me, they would have learnt numerous new techniques along their #IronViz journey; some complex, some simple. For me continuous learning and pushing my boundaries is one of the key reasons I participate in #IronViz, a 4 week feeder allows me to go into detail when it comes to design and storytelling and try techniques which I may not normally consider in a ‘quicker’ viz.

And so we come to this blog, part of a small, short series of posts to share my #IronVizLearning.

I have deliberately chosen to write multiple, shorter blogs on my #IronVizLearning, in the hope this will make the content more accessible to people; and hopefully it might inspire some of you to share your own #IronVizLearning!

The common theme I attempted to apply throughout my ‘Human Development Index’ visualisation was one of maximising the data to ink ratio and eliminating clutter. This theme was heavily influenced by two of my data viz heroes, Ryan Sleeper and Cole Nussbaumer Knaflic, they articulate in their blog posts and books practical ways to reduce ink from your charts and I would thoroughly encourage you to check out their words of wisdom - they say it far better than I ever could!

Simplifying your date axis

My first #IronVizLearning relates to eliminating clutter from your axis. Throughout my #IronViz entry were trend charts, comparing dimensions of the Human Development Index over years. All of the data within my trend charts started at 2000 and ended at 2018. Given this date range would be repeated over multiple charts I made the conscious decision to remove all but the start and end of my date ranges on the axis, resulting in just 2 date labels being visible, those of the years 2000 and 2018.

So that’s the design choice covered, but how did I achieve this in Tableau? I did it through a ‘Tick Marks’ trick that I rarely used prior to this viz.

1. First up I chose to create some white space at the start and end of the viz, ensuring the trend lines didn’t go all the way to the y axis, thus giving the lines room to breathe. This was achieved by giving the date axis a fixed start of 1998 and 2020, i.e. a gap of 2 years at the start and end of the lines.

2. Now time for the Tableau trick. By choosing to start the date axis at 1998 I needed to find a way of labelling only 2000 and 2018. To do this I went to Tick Marks and fixed the Tick Origin to 2 and the Tick Interval to 18. This resulted in Tableau starting the ticks 2 years into the date axis, i.e. 2000 and then displaying the next tick 18 years later, i.e. 2018.

3. Finally, I decided to remove any axis lines from the date axis, resulting in just the year labels being visible.

Here is what this looked like for one of the trend lines in my viz, analysing the trends of the Human Development Index by country within a given region.

The final trend line, alongside the country rank chart (which will be the subject of my next #IronVizLearning post)

If you would like to check out my full #IronViz creation you can do so here.

I hope you have found this first #IronVizLearning helpful, I am planning on sharing a few more over the coming week or two. In the meantime, why don’t you share your #IronVizLearning and inspire the #DataFam with your tips, tricks and design reflections.