Time orientation is crucial for the modern world to understand events and draw the correct conclusions.
The pre-industrial culture had not been so tided to time, and most often people perceived time in cycles as day-cycle or season-cycle. However, industrialization forced on us to create precise time systems and changed circularity to the linear phenomenon.
Currently, the majority of people live within time, and this time has for most of us one orientation from left to right and can not be reversible. It is one of human heuristics – mental shortcut, which helps us understand the world.
Data visualizations best practices tell us to display time on the x-axis with left-right orientation (most of the culture except, e.g. Middle Eastern) and do not play with it especially when charts are going to be short displayed. In the end of August in Polish Public TV, a chart for unemployment rates was presented (see image below) with all possible misleading characteristics. I can not tell if it was intentional or not and politics are not the topic of this post, but let’s have a closer look at how this chart is designed and why it is designed wrong.
I have mentioned above that the human mind craves for mental shortcuts. A quite possible scenario, in this case, can be that receiver reads only the first label for first bar from the left side on the x-axis and understands and remembers that on x-axis there are months of 2020 start from July (Lipiec 2020). The automated interpretation would be that two next bars represent data for two upcoming months, so August 2020 and September 2020. Of course, someone can raise a question in here “We don’t have data for September yet”, but my question is what a level of general data literacy and competency within society is? I am going even further and asking is it ethical to show data visualization for short time without a proper explanation of the graph? But it is a topic for another post. Going back to our example, the conclusion which can be seen is that the unemployment rate has decreased. Where is totally opposite.
However, let’s put ourselves in devil’s advocate shoes and consider, can we approach creatively presenting timeline or not? As I mentioned above, human eyes are used to interpret the timeline from left to right side. Due to that, it is good to keep that order. Sometimes we have a temptation to change it because for example, we would like to compare year over year change and we use last year data as a benchmark. However, that way of presenting data will not be intuitive for receivers. We must be very careful, when we are dealing with data associated with time.
How to fix it?
So how we can fix this visualisation?
First of all, let’s break years into two separate columns and give the time a proper order. Adding columns with years, we clearly indicate that we are dealing in here with two different time stamps. A title or a subtitle itself can help us emphasise that we are presenting a comparison between time points(July 2019 to July – June 2020), so don’t hesitate to include it. Also, I decluttered visualisation by removing background colour and 3d effects, which helps receivers focus only on data. To highlight the most current bar, I changed colour to orange.
All those changes enabled to present data story professionally and properly. Apart from all aesthetic aspects, data visualisation designers need to remember about ethics. The same as in other professions, data visualisation designers have their code of conduct.