The whole DS8 participated in this week’s #MakeOverMonday which dataset consisted in the exports in USD of pharmaceutical products by country from 2013 to 2017. While complex sets of data are generally challenging to work with, I do think that the very simple ones can also sometimes be difficult too. This is especially true during the #MakeOverMonday exercises where you would ideally want to create an original viz.
One way to go for example could be to drill down to a country that presents an interesting story in the data and focus the viz on it. Though I had already used this approach in last week’s makeover so I was keen on trying and learning something new. Because I wanted to see how the top exporting countries evolved over the years I quickly thought of trying to make a bump chart, I had seen it on the web before and had always wondered how to make it. Turns out it’s pretty easy, so here comes my bump chart how to!
The bump chart is actually an overlay of two different charts using the dual axis function, one outputs lines and another outputs circles. Both are generated from the ranking we choose to visualize, so the first step is to create that ranking. This is easily done with a calculated field:
RANK(SUM( [Exports (USD)] ), ‘desc’)
With this field, Tableau will rank the countries from the ones who exported the most descending to the ones who exported the least. After having filtered to the top 10 only, simply drag and drop the newly created field twice in the rows and create a dual axis. Important step, right click on the two fields, hover compute using and select the dimension you are ranking, here it was Exporter. Have the second chart using circles and do not forget to synchronize the axis!
Okay we are nearly there. It looks like Tableau has got the ranks alright but shows them upside down, the last step here is to reverse the axis in the edit axis menu.
Just add the labels and voila, our bump chart is completed!
You can check out my viz following this link. Feel free to ask me any question about it or provide me much appreciated feedback and critics.