A tree map chart gives you a vision of the size of your data by area. The more then area is big, the more the data is important.
With a tree map chart you can see at a glance which element has the biggest size, percentage, value. You can have and example with the New York Stock Exchange on this website.
Source of the data
To create a tree map, you need to have
- A list of data (file name, product name, …)
- The quantity for each item
- Possibility to have a hierarchy between your data
To illustrate this article, we are going to use the export of files from a folder.
Insert a tree map chart
To insert a tree map chart with Excel 2013 or Excel 2016, you just have to follow these steps
- Select your data
- Go in the tab Insert
- In the section Chart, select the hierarchy charts
- Select the Tree Map chart
And you get this chart
Understand a tree map chart
Read a tree map chart is something very easy.
- Each file is representing by a rectangle
- The sizeeof each rectangle is linked to the size of each file. So, when you see a large rectangle, you know that this file is a very large file in your computer.
More, in our example we have using hierarchy data. Each color represents the contained of a folder. So, the organisation of the rectangle is :
- Each color area represents the first folder level of the hierarchy. The name of the folder is visible on the upper left corner of the area.
- The organisation of the different hierarchy area is function of the size. The biggest is always on the upper left position and then it goes down
Inside one area
When you look at the contained of one area, you can see that the items are not sorted by size.
In fact, this is because all the files in this folder + the sub-folders are displayed in the same area. The files are sorted by size and by level but the levels of hierarchy are not visible with this chart.
If you want to visualise the deep of a hierarchy more than the size, it’s better to create a Sunburst chart.