Gantt Chart (Gantt Chart) - one of the most popular tools for illustrating the schedule in project management.
What it is?
The Gantt chart is intended to illustrate the different stages of work in the field of small and medium-sized businesses. Visually, it is a simple set of strips consisting of two main axes: affairs and time. Each time period is assigned a specific task that must be completed.
On the diagram, in addition to the main blocks, there may be a special additional column showing the percentage of work completed. Special marks - milestones - are used to highlight two or more tasks and demonstrate the sequence of their implementation.
The Gantt chart is a kind of standard in the field of project management, because it is with its help that it becomes possible to show the structure of the implementation of all stages of the project clearly.
What is a Gantt chart for?
Given that most people are visuals, the diagram makes it possible to solve one of the main tasks and show the staff what to work on, what resources to use in the process and how fast to perform certain tasks. All information is presented in a compressed form, without the use of confusing tables and a huge amount of text. Moreover, the essence is clear and understandable to all, without exception, the project participants.
Using a chart greatly simplifies the management of small-scale projects and makes it possible to always keep employee activities under control.
The history of the first chart
The first chart format was developed and tested by Henry L. Gant at the beginning of the twentieth century. The scientist was hired to manage the construction of ships for use in the First World War. A special schedule allowed him to coordinate the work of several engineers, monitoring the implementation of tasks on time. Gant began directly by listing all the required tasks and planning them in accordance with available resources.
An important stage was the demonstration of the dependence of some tasks on others. In addition, Gant allocated for each person a period of time during which he had to complete a certain type of activity, indicated who and what task would be carried out taking into account the time allotted for the project.
The construction of the Gantt chart is carried out using a vertical axis representing various tasks, as well as a horizontal representing time.
Gantt chart in the modern world
This planning method does not lose relevance today, because it allows you to provide a graphical display of the production plan, simplifies monitoring of progress in the implementation of tasks. The Gantt chart has become such a powerful analytical tool that it has not undergone any changes for almost 100 years. Only in the 90s of the last century, with the aim of a more detailed description of the relationships, lines of communication between various tasks were introduced into it:
- “Finish-start” - action B cannot begin until the completion of action A;
- “Start-finish” - action B cannot begin until action A begins;
- “Start-start” - action B will begin no earlier than action A;
- “Finish-finish” - action B should end no earlier than action A.
There are facts that the Gantt chart was used in the construction of such gigantic engineering structures as the Hoover Dam (Las Vegas, 1939) and the Eisenhower Highway system (unites most of the major US cities).
Instructions: how to build a Gantt chart in 5 steps?
Next, we will consider the rules for constructing a Gantt chart and try to create it ourselves in the Microsoft Excel spreadsheet processor.
Step 1. Data collection
In order to build a graph, we need the following data:
- coordinates of all data sets (where each of the columns should start from);
- name of each stage;
- the duration of each stage.
For convenience, we enter them immediately into the corresponding fields of the table. After we have entered all the required information, we can proceed to creating the diagram itself.
Important: make sure that all data formats are specified correctly: in particular, dates.
Step 2. Formation of the layout
So, we know the purpose of planning and the key data on the basis of which we will build the schedule. Now, in the tabular processor window, we need to go to the "Insert -> Chart" section, and then click on the "Ruled" item. We need not ordinary, but with accumulation, since only it provides for the second row of data, which in our case will be the main.
Step 3. Erase all unnecessary
In order to do this, the program provides special tools. In the diagram that appears on the screen, you need to move the mouse cursor over the blue bar, right-click on it and select “Data series format” in the menu that appears. A window will be displayed in which we need to go to the "Fill" item and select the "No fill" item. After that, the diagram will look like this:
Step 4. The finishing touches
Since by default all the data in our chart is arranged in the order from bottom to top, we will have to modify it somewhat. To do this, we right-click on the category axis (the one near which we have a list of tasks), go to the "Axis format" window. The tab we need immediately opens - “Axis Parameters”. Check the box “Reverse Category Order”. In fact, the Gantt chart is already ready, only a couple of useful little things remain.
Step 5. Formatting
So, we continue to work on the schedule. As you can see, it still looks ugly, and now we will fix it using the table processor itself:
- Stretch the chart to the desired size using the arrow in the upper right corner.
- Select all the dates in the plate, click on the selection area with the right mouse button and go to "Cell Format-> Number". This section presents the main number formats that we work with. So that the labels do not overlap each other, we recommend choosing a shorter recording option. Then, again, right-click on the axis with the dates on the chart, select "Axis Format -> Number" and put a check mark next to "Link to Source".
- Select the legend (the notation “Date” and “Duration” on the right) and press the Delete button on the keyboard.
- Open “Axis format -> Parameters” and set the minimum and maximum values (we set December 15, since it is Monday, and January 3). Here we can set the price of the main divisions (this is convenient in cases where, for example, work on the project will last several weeks or months). In our case, it is more convenient to leave the default value (2.0).
A few more experiments with formatting - and this is what beauty we get in the end. In front of you is a finished Gantt chart. The example that we have given is, of course, very simple - however, this is enough to understand the essence of such a planning method and to demonstrate the process of performing certain tasks.
Other graphing software
Of course, there are many other, more advanced programs that facilitate project management. Gantt chart of any complexity can be easily built using applications such as:
- Sched roll
- Gantt Designer
- Mindjet JCVGantt Pro;
- Microsoft Project and many others.
In addition, there are a number of online services that provide their users with the opportunity to not only plan their affairs, but also receive regular reports, notifications of the current status of tasks by e-mail. However, one cannot deny the fact that the confidentiality of data stored on the network is at risk, and stationary software installed directly on the user's computer, as a rule, has much wider functionality and is more reliable in operation.
Advantages and disadvantages of the method
Finally, it is worth considering in detail the main advantages and disadvantages of the described method of planning and management.
The main advantage, of course, is the graphical presentation of the material. As a rule, it is convenient for businessmen to work with Gantt charts - they like the ability to clearly identify and outline the stages of work on a project. By presenting tasks in the form of different colored stripes, all team members can literally at first glance determine their tasks.
It should also be noted that Gantt charts are an excellent presentation tool that can demonstrate key project priorities. That is, as soon as executives allocate and distribute each of the available resources, the team instantly finds out about this and follows further instructions. This feature of the Gantt chart is extremely useful for senior managers - using it, it is much easier to prepare a detailed, comprehensive report on the status of various projects.
However, like any other planning method, the Gantt chart has its drawbacks. One of them is the dependence of tasks. Quite often, in the process of presenting projects , managers need to show which of these tasks are related to each other. But, unfortunately, the chart format itself does not allow this. In order to get around this limitation, managers resort to various tricks: for example, they add special vertical lines to the chart that demonstrate key dependencies. However, this is only a temporary solution, not able to transmit information in full.
Another disadvantage of Gantt charts is their inflexibility. Nowadays, projects are not static - they are constantly undergoing some changes, shifts, which are simply impossible to take into account in the diagram. Before starting to build a schedule, managers have to calculate everything to the smallest detail, because with the slightest change in the assessment, you need to redraw the entire chart from scratch. And this is not to mention the fact that the ability to illustrate several different planning methods at a time is also absent.
Regardless of why you need a Gantt chart, a program (even the most “advanced” one) will not be able to display the significance and resource intensity of certain works, their essence. And therefore, for especially large-scale projects, it is used extremely rarely.
Nevertheless, it is impossible to deny that in the practice of project management this method is extremely widespread - for more than a century of history of its use, people have had the opportunity to be convinced of its performance and high efficiency.