Controlling Project Schedules

Another input to project schedule control is the project schedule. Project schedules are a set of planned dates for performing activities and meeting project milestones.

Project schedules are not considered complete until they have been approved. The approved schedule is known as the schedule baseline. A schedule baseline is a fixed project schedule that is the standard by which project performance is measured.

The schedule baseline is only adjusted when the project's scope has been significantly altered as, for example, when the project scope has changed.

When baselining a schedule, you need to consider project activities, dependencies, estimates, constraints, assigned resources, and resource availability.

• Activities - Before baselining a schedule, it must be as complete as possible with regard to identifying all of the project's activities. If you overlook an activity, the schedule may need to be altered in order to add the activity later.
• Dependencies - Network logic must be included in the schedule. Dependencies from other projects should also be considered. If, for example, you plan to start Project C on March 1st, but the resources will not be available until Project B is complete, this dependency must be built into the schedule.
• Estimates - Estimates for activity duration and work effort must be reasonable. If you allot only 60 hours for a 100-hour activity in an attempt to cut costs, you are setting an unreasonable estimate which will affect the effectiveness of your entire schedule.
• Constraints - All known constraints must be accounted for. If an employee needed to complete the project is only available for three months, you must account for this constraint in the schedule and make every effort to utilize this resource within the time he is available.
• Assigned resources - Resources must be assigned to activities in a realistic manner, for example allowing for vacations and down-time. Resource requirements must be reviewed and compared to known capacity.
• Resource availability - The scheduled dates must take resource availability into account, which means the schedule must be leveled manually or automatically. If you know that a supplier can only deliver its resources at the end of phase one, you should not schedule the activity until then.

The schedule can be baselined and used to measure project progress once you have carefully considered these project schedule inputs. Then with a baselined schedule in hand, you can begin the process of deciding which method to use to present the project schedule data.
Tom, the new project manager for Askme Consulting, is beginning his first project: constructing a new office complex in Manhattan. He is reviewing the work breakdown structure developed in the initial planning and estimating stage of the project proposal. Tom and his management team meet to determine the most appropriate method of presenting the schedule for this extensive project. The team needs to determine the types of information required when reporting the project's progress and predicting its future.

The methods they are considering are: the milestone chart, project network diagram (PND), time-scaled network diagram, and Gantt chart. The method they choose will depend on the variables they need to monitor and control as the project progresses.

• A milestone chart is a summary-level schedule identifying the major activities or deliverables of the project. It can become the skeleton for the master schedule. A milestone typically marks the end of an event or the completion of an activity. For example, the first milestone activity for the Askme Consulting project is architecture/design. The second milestone activity is the foundation work.
• A project network diagram (PND) is a schematic display of the project's activities and the logical relationship between them.
• A time-scaled network diagram is a variation of the PND. The positioning and length of the activity represent its duration.
• A Gantt chart is a graphic display of schedule-related information. A typical Gantt chart displays activities, dates, and durations. Gantt charts are the most convenient, commonly used, and easily understandable method of data presentation for project planning, resource scheduling, and status reporting.

Once you are familiar with the various methods of displaying project schedule data, you can use the information for conducting performance analysis. The Critical Path Method (CPM) plays a vital role in this analysis process. Critical Path (CP) is a series of activities that determines the earliest possible completion date for the project.
CP is the longest full path in the project. CP activities have little or no float. As activities are completed, the critical path may be altered. The CP can be determined for the entire project, a milestone activity or a sub-project.

The CPM is used to predict project duration by analyzing which sequence of activities or path has the least amount of scheduling flexibility or float. The early start and finish dates for each activity appear above the node on a Project Network Diagram. The late start and finish dates for each activity are below the node.

Early dates are calculated by means of a forward pass using a specified start date. Late dates are calculated by doing a backward pass, starting from a specified completion date. The most effective way to ascertain the critical path is to perform a forward and then a backward pass through the project.

To perform a forward pass, look at the first activity and determine its earliest possible start date. This is called early start. Continue this process for every activity.

To perform a backward pass, start at the last activity and determine the latest each activity can start without affecting subsequent activity. This is called late start.

Once you have completed the forward and backward passes, you must examine the results. If early and late start dates for an activity are the same, the activity is on the critical path. If there is a difference between the dates, the activity has float time and can be placed on the non-critical path.

Project schedules help you plan dates for performing activities and meeting project milestones. Schedule baselines and critical paths are important aspects of the schedule because they help in project schedule control. Together, these project scheduling tools and methods help project managers to monitor and measure project progress.

Compressing Project Duration

Have you ever heard the saying, "You may delay, but time will not," by Benjamin Franklin? As a project manager, don't you sometimes wish that you could just stop the clock? This is especially true when a project's schedule needs to be shortened so it will be finished before its scheduled date.

You could use duration compression to shorten the project schedule. PMBOK defines duration compression as, "shortening the project schedule without reducing the project scope."

There are two duration compression techniques commonly used by project managers to meet imposed dates or other schedule objectives. These techniques are: crashing and fast tracking.

Crashing
Crashing a project schedule involves analysis of cost and schedule trade-offs to obtain the maximum duration compression (shortening of the project schedule without changing the scope), with the least amount of cost. This technique is usually the last choice for project managers.

Crashing the schedule may not always be the most feasible option for your project. It often results in increased project costs and the addition of extra resources. The rules of thumb for crashing a schedule are always crash or shorten tasks on the critical path and choose to crash tasks that will have the least impact on the project's budget.

Consider this example. Palmcom Computers has just reviewed its draft schedule for a new computer design project. It has discovered that the original plan has to be crashed to complete the project sooner than initially anticipated. Palmcom realizes that the objective of crashing its planned schedule is to come up with the best project end date.

Since crashing involves building a plan without regard to resources, Palmcom has restructured its schedule to include additional resources.

Fast tracking
Fast tracking involves looking at a project plan and assessing when it is practical to do work in parallel instead of sequentially. It works best where there are activities that are somewhat independent of each other. Fast tracking the schedule compresses the project schedule by overlapping activities that would normally be done in sequence, such as design and construction.

Consider this example. Sol-car, an automobile manufacturer, is designing a new solar-powered vehicle. Sol-car has just been notified by a major supplier that the panels it has ordered will not be available until May 15. The company has recently announced that it will unveil this new automobile on June 21. Therefore, this delay in shipment may cause a delay in the project's completion date.

Based on this information, Sol-car reviews its project schedule. It has decided that the last phase of the project will have to be adjusted to compensate for the previous delay. The last phase of this project would include the body assembly, the frame construction, the painting, and the final testing and marketing. The network diagram on the left is the original schedule, and the diagram on the right is the fast tracked schedule.

Looking at this schedule you can see that the activities are sequential in nature, with a finish to start dependency. This means that the preceding activity must be completed before the next activity can start.

Sol-car has fast tracked this schedule by moving activity D, which is somewhat independent of the other activities. Activity D will run concurrent to activities B and C. However, this can only occur if activity D's required resources are available.

Although these methods of project duration compression may seem like the answer to a project manager's prayer, there are disadvantages that should be taken into consideration. Can you think of what these disadvantages might be?

Fast tracking often results in rework and increases risk of a project being over budget. For example, there is an increased risk that the activity will not be performed properly when activities are overlapped. If this does occur, the activity will have to be redone.

Crashing often increases a project's cost. For example, if additional resources are added to crash a project activity, the labor costs on the project will be more than originally anticipated.

Although there are risks involved with duration compression, the ultimate goal is to bring a project back on track and end up with an improved, shorter duration. Either crashing or fast tracking will help you achieve that goal.

Evaluating an IT Project

To ensure your IT project is on track, and to prevent serious performance issues, you should evaluate the project at the end of each of the six project stages. Usually, the end of a stage is identified by the completion of a project deliverable. An evaluation process can help your team determine whether changes need to be made to the process or plan before moving to the next stage.

After working diligently to reach the end of each stage of the project, it is important for all team members to meet to discuss the negative and positive aspects encountered up to this point. The focus of this meeting is to evaluate the activities and variables for each particular stage in the current project's development.

For example, during the evaluation, the team may determine that the project scope has changed, the team has not been as productive as planned, or necessary tasks have been left out. These are all variables that can lead to missed deadlines.

During the evaluation of an IT project's development, it is essential to consider two main business activities. The two business activities that should be the focus of the project evaluation are described below.

1. Estimate schedule performance.
Processes that should work harmoniously together sometimes do not. Your team may find that these unforeseen circumstances can dramatically slow down development. You then have to stop and reevaluate the process. This can sometimes be very time consuming.

Your team can estimate schedule performance by comparing the schedule estimates with the actual work completed. A formula for measuring schedule efficiency is the schedule performance index (SPI).

SPI is the schedule efficiency ratio of earned value (EV) accomplished against planned value (PV). The formula is SPI = EV ÷ PV x 100. In this formula, EV answers the question, "How much work has actually been completed at this point?" PV answers the question, "How much work was scheduled to be completed by now?" To round the SPI, look at the digit to the right of the place to which you are rounding. If that digit is less than 5, round down (6.45 = 6). If that digit is equal to or more than 5, round up (6.51 = 7).

When analyzing SPI for a project, you must consider the results from the calculation. A result equal to 100 indicates that the project is performing as estimated. A result that is greater than 100 indicates that the project is performing ahead of estimates. A result of less than 100 indicates the project is behind estimates.

Managers prefer to see the schedule hit within an acceptable range, where 85 or 90 out of 100 is considered acceptable. When the result varies significantly below 100, risk analysis will be necessary.

2. Evaluate team member performance.
Another business activity to evaluate is team member performance. The wrap-up at each stage of the project is an ideal time to evaluate whether the team has met the goals of the project plan.
It's important to evaluate the performance of team members to ensure they meet completion dates for each task, as documented in the project plan. Valuable time can be lost when even one member of the team does not meet individual goals. With each task set up to flow smoothly into another, a deviance from the established plan can cause major problems.

How can you determine whether team members have met project goals? You can establish a performance expectation for each task prior to beginning the project. The completion time for each task is normally estimated using an average work week of an eight-hour day and 40 hours. The equation you can use to determine completion time for a task is: number of estimated hours for completion ÷ 8-hour day = time allowance in days.

For example, if the task is estimated at 20 hours, then it should be completed in 2.5 days (20 ÷ 8 = 2.5) to be on schedule. If a task is estimated to take 2.5 days and it actually takes three days to complete, then the task has missed the deadline. If the task is completed in less than 2.5 days, it is ahead of schedule.

Do not underestimate the importance of evaluating your project's development. An evaluation at the end of each stage of your project can prevent serious performance issues as the project progresses.