Page 59 - The Six Sigma Project Planner

Gantt Charts
A Gantt chart shows the relationships among the project tasks, along with time
estimates. The horizontal axis of a Gantt chart shows units of time (days, weeks,
months, etc.). The vertical axis shows the activities to be completed. Bars show the
estimated start time and duration of the various activities. Figure 9 illustrates a simple
Gantt chart that can be created by hand. There are many types of Gantt charts, limited
only by the needs of the project. The Gantt chart should show activity dependencies.

Figure 9. Gantt Chart of Schedule

Activity Week 1 Week 2 Week 3 Week 4
1
2
3

4
5

6

Milestone Charts
Gantt charts are often modified in various ways to provide additional information. One
common variation is shown below. The milestone symbol (♦) represents an event (a point
in time) rather than an activity (an interval of time). Unlike activities, milestones do not
consume time or resources. When Gantt charts are modified in this way, they are
sometimes called milestone charts. In the milestone chart below, uncompleted activity
durations are shown as unfilled boxes. As activities are completed, the boxes are filled in.
Figure 10. Gantt/Milestone Chart of Actual vs. Scheduled Performance

Activity Week 1 Week 2 Week 3 Week 4
1 (100%)
Today
2 (50%)
3 (50%)
4 (milestone) ♦

5 (not started)
6 (not started)
7 (not started)

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