The PM Procedure

Example 3.3: Saving and Comparing Baseline Schedules

This example shows you how to save a baseline schedule and use it for comparing new schedules. Recall that in Example 3.2 the Schedule data are saved in the data set SOFTOUT1. Thus, the following invocation of PROC PM displays the Software project in its last saved state (as in Output 3.2.2, but with the WBS codes filled in). At the end of the editing session, the schedule is saved in the data set SOFTOUT3.

  
    proc pm data=softout1 project=softattr 
            date='1mar04'd interval=weekday 
            projname='Software Project' 
            out=softout3; 
       act actid; 
       succ succid; 
       project pntid; 
       duration duration; 
       id activity; 
       run;
 

Use the Edit -> Set Baseline pull-down menu (Figure 3.27) to save the current Early Schedule as a Baseline Schedule. The resulting display is shown in Output 3.3.1. Note that the Gantt View now shows the Baseline Schedule in addition to the Early Schedule. Also, the activities have been numbered to be sequential in the current view (see the section "Renumbering the Activities").

Output 3.3.1: Using Baseline Schedules

The baseline schedule is useful in determining the effect of changes to the project on the schedule. For example, suppose there is a directive from the director of your division that all the developers are required to attend a User Interface Standards Meeting before starting the development of Module 2. This meeting has been scheduled to start on March 15, 2004, and is expected to take 3 days. What is the effect of this directive on your project schedule?

To see the effect, you can make the following changes in the PM window:

1. Add a new task to the project by selecting New Task from the Edit pull-down menu.
2. To edit the newly entered task, you may need to scroll down.
3. Type in the name of the task: 'UI Meeting.' Set its duration to 3.
4. In the Gantt View, draw a link from this new task to Task 6 ('Module 2' under 'Develop.')
5. Also in the Gantt View, drag the task, 'UI Meeting,' to the tick mark corresponding to 15Mar04.

The resulting view is shown in Output 3.3.2. Note that the view may differ depending on the display parameters of your device. It is easy to see that, due to the 3-day meeting that is mandated, there is a delay in the project schedule (the project duration is now 26 days).

Output 3.3.2: Effect of UI Meeting on Schedule

You can get a complete picture of the effect on the schedule by examining all the Schedule columns that are shown in the Table View. Output 3.3.3 shows the Schedule columns, the Baseline columns, and the Target Date and Type columns in the Table View. To obtain this view, some of the columns have been moved and the Baseline Schedule bars (in the Gantt View) have been hidden from the display.

Output 3.3.3: Table View Showing All Schedules

If the project delay resulting from the UI Meeting is of concern, you may want to schedule the meeting on an earlier date. Suppose the revised start date of the meeting is March 10, 2004. To see the effect of the change, you can do the following:

1. Revert to the saved project preferences so that both the Table and the Gantt Views are visible.
2. Use the View menu to move the Target Date column to the left in the Table View.
3. Scroll down, if necessary, to bring the task 'UI Meeting' into view.
4. Change the Target Date column for this task to '10Mar04.'

The resulting view is displayed in Output 3.3.4. Note that, as a result of this change, all the activities are back on schedule as the new schedule coincides with the saved baseline schedule. The last activity was defined after the baseline schedule had been saved in Example 3.2; hence, there is no baseline schedule bar for this activity. You can use the Fill Missing Baseline selection from the menu shown in Figure 3.26 to set the baseline schedule for the 'UI Meeting' to be the current early schedule.

Output 3.3.4: Editing Target Date