Creating a PERT chart, bar graph, flowchart, Gantt chart, or process control chart are some ways project managers take control of simple and complex projects. These charts visually represent data in an easily understandable format to ensure complex project management concepts become simpler.
These charts also help evaluate the time, resources, interdependencies, and critical paths in a project. While there are multiple graphs and charts used, this article takes a closer look at the PERT chart and Gantt chart.
Gant charts are one of the commonly used variants of the bar chart. The vertical axis represents the project tasks and the horizontal axis denotes the timeline. Developed by an American engineer, Henry Gantt, the chart depicts many elements of the project including milestones, resources, timeline, and dependencies.
Several industries and projects right from bridge or highway construction to software development make use of Gantt charts to plan projects.
It is suggested that one follows these steps:
- Collect inputs from all teams on the scope of the project and the work breakdown structure (WBS)
- Break down each WBS into activities
- Identify milestones and deadlines for activities and the entire project
- Place the activities in the appropriate order to show their dependencies
- Estimate resources
- Schedule the tasks.
The key advantages of a Gantt chart include:
- All stakeholders are able to view the schedule information, which helps establish common expectations and drive collective effort
- It is an easy visual timeline that denotes the start and end of activities
- It identifies the critical path (any delay in the critical pathway will lead to delays in other tasks).
The disadvantages of a Gantt chart to consider include:
- Creating and managing a Gantt chart takes quite a bit of effort
- Updating the chart is time-consuming
- Lack of a single-view of all the tasks – scrolling and clicking on additional buttons to see remaining items is required
- Realigning the tasks between sections is not easy
- Stacks represent only the time and not the number of hours.
When you are looking for a single-view of all tasks and to conduct a feasibility study at the project planning stage, a PERT chart may be a better choice.
PERT stands for Program Evaluation Review Technique and is a powerful project management tool. Project managers use the PERT chart to graphically and visually represent a project’s timeline.
PERT charts were created by the Special Projects Office of the U.S. Navy in 1957 to simplify the planning of complex projects such as the Polaris nuclear submarine missile program. A PERT chart is drawn by using circles or rectangles (called nodes) to denote the project milestones or events. Arrows or lines that symbolize tasks are used to link the nodes.
- The rectangles or circles contain the event or milestone that has to be achieved in a specific timeline
- The directional arrows show the sequence of dependent tasks to be performed for project completion
- Parallel or divergent arrows show concurrent tasks that can be either sequentially or simultaneously performed
- Dotted lines are used to show dependent activities that need no resources.
A clear overview: Apart from showing the length of time it will take to complete each milestone and the entire project, a PERT chart shows who in the organization is responsible for those tasks and the task dependencies.
Resource and time planning: A PERT chart enables project managers to assess the resources and time required to manage a project. The chart helps managers track the assets they need at any stage of the project.
Encourages ownership: With information and data input used from multiple departments to draw up a PERT chart, it encourages each team to take responsibility while identifying responsible departments across the organization.
Promotes communication: By identifying dependent tasks, it fosters inter-department communication. The PERT chart helps the organization prioritize projects aligned with its strategic objectives.
Boost efficiency: PERT charts are designed to be used during the planning phase of the project to understand the process as well as to conduct a feasibility study. The chart can also be used to analyze different possibilities that help identify the most cost-effective and efficient project path.
Milestones are the goals and the tasks are action steps that help you achieve these goals.
While determining the sequence of tasks, identify task dependencies.
One way to define task and milestone timelines is to use the critical path method (CPM). According to this technique, each task has three possible timelines – pessimistic (the maximum time estimate for completion), optimistic (earliest date/time), and the most likely timeline.
Ensure you have all of the information from all of the departments before you begin creating your PERT chart. You can use these downloadable templates to remove the hassles of creating a PERT chart from scratch and optimize project management.
While you progress, you can easily update the chart using the PERT chart template.
The primary objective of charts and graphs is to graphically present information which makes it easy to grasp for all stakeholders. Apart from ensuring the efficiency and efficacy of the project, these charts allow the manager to get an overview of the tasks and the project, while spotting issues at an early stage. With timely delivery of tasks, the project is well on its way to becoming successful.