A First Look into the New Sankey Chart Type in Tableau

As an enthusiastic user of Sankey charts, I am excited to learn that a Sankey chart type is being piloted in Tableau Public (Web Edit only). I wrote about Sankey chart design in multiple posts. Sankey chart may appear in different forms depending on applications. 

I played a little with it just to evaluate it. Here are my initial findings and comments.

1. The basic Sankey

I can quickly create a Sankey with 2 dimensions and 1 measure. This is great! 

I noticed that two new marks cards are being used: Level and Link. The two dimensions are placed in Level card and the one measure is placed in Link card.

Comments:

- The text labels are showing by default and not editable. I understand the design choice. More details can be put in the tooltips. Note that the measure is showing in percentage and not the measure itself. That's fine in Sankey. But I hope we can format the percentage. Currently we can't.

- The Label card is no longer the same as in other chart types. The labels have option to show on links/branches that are selected or highlighted or both.

- The Color card provides options to a number of color palettes. We as user can't assign color to each member of a dimension. It's pretty rigid. The coloring of the links follows that of the left level/dimension with a lower opacity. I wonder if we should have option to use the colors of either left or right level/dimension for those of the links.

2. Sankey with Level Padding

We can add vertical spaces between the members in sidebars. This is what we have been doing when creating Sankey charts. The option is in the Level card as shown below. This is being called Level Padding. The padding size can be adjusted appropriately. 

3. Sankey without Sidebars

In the Level card, we can minimize the sidebars by adjusting the Level Width.

Comment:

I would ask that we have the option to minimize/hide either of the sidebars. The need arises in the building of multi-level Sankey chart, where we cascade single Sankey's. Then one of the two sidebars in a single Sankey would be redundant. We need to be able to hide/minimize it. 

This way, we will expand the utility of the Sankey chart type to building multi-level Sankey chart.

4. Sankey Label Showing when Selected or Highlighted

In the Label Card, we have the option to only show labels when a branch is selected or highlighted. This is neat, saving some effort of creating action filters.

5. Further expectations

Funnel chart is an important chart. It can be derived from multi-level Sankey chart. This can be done with a few more hiding options and cascading. The hiding is for a subset of members in a sidebar level/dimension.

6. Summary

Overall, the new Sankey chart type is easy to use. I am very happy about its pilot trial.

With a few additional tweaks, I think it can be applied to a wider area of use cases such as multi-level Sankey chart and Funnel chart.

The above example charts can be viewed on Tableau Public and explored in Web Edit. But you can not download it because the pilot is in web edit only.

Follow up post: Multi-Level Sankey Chart via the New Chart Type in Tableau