A Gantt chart is a type of bar chart used for project management and is named after its inventor, Henry Gantt. The chart outlines the tasks to be performed on the vertical axis and time on the horizontal axis. It is used to keep a record of actual and estimated completion dates of tasks in a project plan. The difference between the actual and the planned dates highlights the deviation in the delivery of the assigned task in each project phase.
In this guide, you will learn how to build a Gantt Chart in Tableau. This is easy to do, and requires the following basic components:
Mark type as Automatic or Gantt Bar
Mandatory date variable, which will be in Columns shelf
One or more dimensions in the Rows shelf, highlighting the phases or project activities
In this guide, we will be using fictitious project data consisting of six variables, as described below.
Project: The major project area, such as Revenue, Expense, etc.
Tasks: This variable includes four activities: Requirement Gathering, Wireframing, Development, and UAT.
Assigned: Name of the person to whom the task is assigned.
Start Date: Indicates the start date of the task
Duration: Indicates the duration of the task
Status: Indicates whether the task is Completed, In Progress, or Not Started
We'll follow the steps below to build the Gantt Chart.
Start Dateto the Columns shelf and select the date aggregation at the day level, as shown in the chart below.
Assignedin the Rows shelf. This provides the information about the project, its tasks, and the individuals assigned to complete them. It also provides the start dates of the various tasks.
Durationvariable into the Size property of the Marks shelf. The size of the bar will vary in accordance with the time taken or the time it will take to complete that task. Please refer to the below chart.
Developmenttask seems to be of higher duration, while the
Wireframingis a shorter duration task. We can also observe that the tasks are not properly sorted because
Developmentcomes first, followed by
Wireframing. The correct sequence for this project is
To correct the sequence, we need to sort the task field in the Rows shelf. To do this, the first step is to right click on
Tasks and select Manual sorting from the pop-up display list, as shown in the chart below.
When you click on the labels, the arrows on the right-hand side are enabled, after which we can simply sort by clicking on that label. Alternatively, we can drag the labels directly into the desired sorting order, after which the project tasks will be displayed in the desired sequence, as shown in the chart below.
The next step is to use the DATEADD function in Tableau to calculate the end date. To do this, we start by naming this calculation
End Date and then pass in the argument
DATEADD(‘day’, [Duration], [Start Date]) in the calculation box. We are passing the day argument in the above function as we want the aggregation to happen at a daily level. The function will simply add the days to the start date and will provide us with the end date.
Statusvariable in the Color property of the Marks shelf. Then we will edit the colors and assign green to Completed, orange to In progress, and red to Not Started, resulting in the following chart.
End Dateinto the Label property of the Marks shelf. This will produce the following chart.
Todayby calling the function Today() and then dragging it to the Detail property of the Marks shelf. This is illustrated in the chart below.
a. Select value
DAY(Today()) from the drop-down
b. Select label
c. Format the reference line by selecting the desired way to show reference line
This can be seen in the chart below, which creates a reference line that acts as a baseline. It also helps in tracking how many and which tasks have been completed, are in-progress, or have not yet been started.
The final chart after completing all the steps discussed so far is displayed below.
In this guide, you have learned the steps to build a Gantt Chart in Tableau. You also learned about its philosophy and application in the project management context. The knowledge you have acquired will help you track the progress of project tasks, plan mitigation strategies, and realign resources to ensure projects get completed on time.
To learn more about visualization and data analysis using Tableau, please refer to the following guides: