New in Tableau 8: Treemap Bar Charts

Treemaps aren’t new – they’ve been around for a few decades, and yet they remain a powerful and compact way to visualize hierarchical and part-to-whole relationships. Tableau 8.0 has them, too.

What isn’t so common, however, is a way to create multiple interactive treemaps and easily arrange them into a bar chart for comparative purposes. Say hello to treemaps in Tableau 8.0!

But why not just embed everything into one treemap? Why put separate treemaps side-by-side in a bar chart? Let’s consider the following example of cash and debt carried by the Top 50 US Companies by market cap:

Now, of course, cash and debt are two very different things. Furthermore, they don’t sum up to anything particularly meaningful in this context because companies have other line items on the balance sheet such as inventory and assets. Comparing the overall amount of cash and the overall amount of debt is interesting, though. And what more accurate way to compare two values than to use a bar chart?

This way of visualizing the data allows the following questions to be answered with accuracy and speed:

1. Do the top companies put together have more cash or more debt? By how much?
2. Of the top companies, which industries have the lion’s share of the cash (and separately, the debt?)
3. Within each industry, what are the top cash (and debt) holding companies?

It’s slightly more difficult to examine one particular company – whether it has more cash or more debt – because the rectangles are embedded in separate treemaps and have different lengths AND widths. A tornado chart similar to the original version of this visualization would facilitate a single company comparison, so for this reason the overlapping data table appears when a company box is selected.