A treemap is a data visualization diagram that configures a chart using hierarchical data in rectangles of different sizes. This technique is also called Nesting. A treemap chart uses colored and nested rectangles, which you can consider as branches.

Below, you will find some reasons why you should use this descriptive type of chart to understand some statistics of your business.

• Treemap charts are fundamental to your company or project when you compare data in two quantitative values. This way, each rectangle represents the quantity of a specific item and it’s easily comparable with the rectangles next to it.
• Using a treemap chart is an excellent method to understand how your business progresses.  
• Your business has a wide area size and a large amount of hierarchical data to improve processes and statistics. 
• A treemap chart provides a high-level summary of the similarities and anomalies inside each category, sub-branch, and between multiple categories.
• You can organize all the data of your organization at several levels.

Treemap charts are characterized by specific elements and nodes, which we will describe below:

• Treemap charts display hierarchical data using nested rectangles.
• Each rectangle represents two numerical values.
• The size and the plot colors of the rectangles are strictly related to the quantitative variables of the measure.
• The data can be multi-layered through a series of nested rectangles where “child elements” are tiled along with “parent elements.”
• The section of each rectangle is proportional to the percentage of the rectangle compared to others. 
• A branch is made up of a sum of subcategories.
• Rectangles are organized in decreasing order, with bigger ones in the top left corner and small ones in the bottom right corner. 

As a treemap chart is a hierarchical visual representation of a data tree and specific data points, it’s best to begin with the most relevant information or category. Then, it would help if you used the first column – column A – to insert the main categories. Then use the subsequent columns to insert the subcategories or corresponding numerical values.

To create your treemap chart, select your data. Then, go to Insert tab > Insert Hierarchy Chart > Treemap. 

By default, the name of the chart is Chart Title. Right-click that text box and enter the name of your preference. Now, you can select a style, a different layout, or a color scheme for the treemap. 

Select the treemap chart and head to the Chart Design tab that displays. You can use various tools in the ribbon to personalize and customize your treemap.

You can configure a different color for top levels and use the layout of the data labels between the categories by right-clicking on the rectangles on the chart. 

Note. Another way to create your treemap chart is to use Recommended Charts. Go to Insert > Recommended Charts > All Charts.

• Thanks to treemap charts, you can identify data values and patterns and discern relationships between different components through hierarchically organized data. 
• It is easy to display hierarchies, even when showing dozens of parent categories and hundreds of data points or sub-branches. 
• Treemap charts accurately display elements and spot patterns. For example, how many units sold correspond to a determined period.

• All the values in a specific variable representing the size of the rectangle must be positive.
• Treemap charts do not show the hierarchical levels as clearly as other charts, such as the Sunburst Diagram or the Tree Diagram. 
• Readability can be challenging to understand, like many other tree maps. Linear data plots are easier to read than large and wide ones.