WBS Summary | Primavera Scheduling

Jul

The Rookie Resource Mistake

Categories: Level of Effort, P6 Professional, P6 Tricks, Primavera P6 Baselines, Resources, Uncategorized, WBS Summary

Tags: Baselines, Earned Value, Primavera P6, Resources

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by Bill Pepoon

In one of my favorite Gene Hackman films, Heist, there is a scene where his character is explaining how he solved a problem. His client (actually, a mobster he is planning to rip off) says, "you're a pretty smart guy." When Hackman's character declines the compliment, the mobster replies, "then how did you figure it out?" Hackman's response:

"I said to myself, 'what would a smart guy do?'"

I love that line. Unfortunately, I recently forgot that lesson. Let's set the stage. I am updating a new Primavera P6 schedule for the first time. I have a change order modification that has been added, and there is also progress on this new activity.

The client told me he is 40 percent complete with the modification. So I type in that percentage. And I move on with the update. But while checking my customized earnings report I realize there is no Earned Value for the new activity. But the activity is in fact showing 40% complete.

Okay...

Now, perhaps you are thinking I forgot to apply an actual start date. Well, no, it would not be possible to show a percent complete without first entering an actual start date. I should also mention that I am using the Physical % Complete type so that I can enter whatever percentage I want.

Hmm. Perhaps there is something wrong with the way I cost-loaded the activity. Nope, it has a budgeted total value. And I am using the same resource that all other cost-loaded activities have been assigned in this particular schedule.

What about my Earned Value settings? I almost never change them, but I verified that Performance Percent Complete = Activity % Complete (Admin > Admin Preferences > Earned Value). In the construction industry that is pretty much the setting that everyone uses. The point being that the activity percent complete determines Earned Value.

Yet here I am, still looking at zero dollars earned and 40% complete.

Aha, must be the activity type! We know that certain activity types like Level of Effort and WBS Summary behave differently than other types of activities.

Sorry - the new activity is Task Dependent. Nothing to see here folks. And if you were thinking it was a milestone, keep in mind that milestones cannot be assigned resources due to their zero durations.

What would Gene Hackman do?

He'd probably say something like, "hey buddy, if Earned Value is working on EVERY other activity in the schedule then there has to be something different about this one."

But it's not different, it's just new.

Oops...

Yes, it is a new activity! And where does Earned Value come from?

The baseline to the current schedule!

Under the Settings tab in the Project Details window there are two options for calculating Earned Value: Project baseline or User's primary baseline.

My schedule was set to Project baseline, and my Project baseline is the original plan. The new activity doesn't exist in the original plan so Earned Value is automatically zero.

I knew this, of course, but it is easy to forget when you are in a hurry. And it seems rather odd that users who never create baselines for the current project are immune to this potential problem. Because when there are no baselines the current schedule IS the baseline!

This is in my mind one of the most counter-intuitive aspects of Primavera P6. Earned Value is not always based on the current schedule. Why would I want to base my earnings on something other than the current schedule? If the budget has changed it seems logical to pay off the new budget.

Now, I prefer not to change the value of an existing activity for pretty much the same reason I don't change the original durations. I want to preserve the old values for future reference. If the duration or budget is changed by a modification I will add a new activity for that purpose.

I have had a few projects, however, where we re-balanced the activity budgets. Assigning any baseline other than the current schedule would clearly cause problems. Which brings up another concern: the Earned Value for a project can be okay one day and off the next if a different baseline is assigned. Fun!

When I mention this during training sessions I often hear someone with a little Primavera P6 experience say something like, "never happens to me". Yes, that could be true. If you don't typically create baselines then by default your baseline is the current schedule. Lucky you!

Those of us who utilize baselines on a regular basis have to be more careful. And it gets rather complicated when there is more than one baseline attached to the current schedule. Re-assigning a baseline can change Earned Value. Oh well. I'll just keep channeling Gene Hackman.

Apr

My Least Favorite Activity Type

Categories: Activity Types, Level of Effort, P6 EPPM, P6 Professional, WBS Summary

Tags: Activity Types, Level of Effort, Primavera P6, WBS Summary

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by Bill Pepoon

While I consider my self pretty adventurous when it comes to Primavera P6, I admittedly have little use for one particular activity type, the WBS Summary. To review, the WBS Summary calculates its Start and Finish date (and therefore, duration) from all other activities that have the same WBS code. On the surface, this seems like a great idea because logic is not required. The WBS Summary is the only activity type in Primavera P6 that works sans logic. And this is what I do not like about it.

I always check the Schedule Log before I publish a schedule. As you should know, the Schedule Log has a topic called “Warnings” that discusses, among other concerns, the number of activities that are missing predecessors or successors. The correct number of “open ends” would of course be two; the first activity will not have a predecessor and the last one will not have a successor. No other answer is acceptable. Owners will also be checking the Schedule Logs during their reviews. Open ends are an easy way to get a schedule rejected.

Because the WBS Summary does not want or need logic, it creates what appears to be a de facto mistake in the schedule. If the person reviewing the schedule figures out that the open ends are due to this particular activity type, then perhaps they would accept the schedule regardless. But it has been my experience that owners do not want to hear any excuses as to why some activities have logic and others do not. Open ends are an unnecessary distraction from other items (sequences, durations, coding, etc.) that need to be checked.

It is possible to add relationships to a WBS Summary to make the open ends disappear, but this basically defeats the purpose of having them in the schedule in the first place. Why not use the Level of Effort instead? The Level of Effort also calculates its dates and duration automatically, but requires logic. Therefore, the Level of Effort does not create any concerns in the Schedule Log. Both of these activity types can also have resources assigned, so nothing is lost by switching to the Level of Effort.

Logic can be added to a WBS Summary without affecting the way it calculates its dates and duration, but again, why not use the Level of Effort instead? While they may seem interchangeable, the Level of Effort demands logic, and therefore forces us to add proper relationships. The WBS Summary is a little too accommodating. I want my activity types to enforce good habits!

Better still, the Level of Effort can transcend more than one WBS code which makes it far more flexible than the WBS summary. If I really need to see the dates and durations for WBS codes I can Group by WBS and choose to Show Group Totals. This saves me the trouble of adding a bunch of WBS Summary activities to my schedule for no other purpose than seeing summary dates and durations.

In the screenshot below, the WBS Summary activity is purple. Yes, this activity tells me the Foundations start on May 17 and finish on June 28, 2016 and have an overall duration of 30 days. Yet the same information appears in the Group Totals:

So there is no additional benefit to adding the WBS Summary activity if the only information being provided are the summary dates and duration.

I know some users are adding WBS Summary activities as a simplified way of cost loading a schedule from the top down. They put all of the costs in the WBS Summary activities rather than the actual work tasks. But Primavera P6 has a tool called Top Down Estimation that is better suited for that purpose. While it is possible to specify a non-linear distribution curve for resources, the reality is that you are still treating every day as having the same value. That is simply unrealistic.

A Primavera P6 compatriot did mention to me a reason why he uses the WBS Summary activity on a temporary basis. When Microsoft Project schedules are imported into Primavera P6, the summary bars are imported as activities. He uses the Microsoft Project summaries as temporary placeholders for checking logic and durations. Similarly, I will use the descriptions of the Microsoft Project summary activities to build my WBS codes before deleting these superfluous tasks,

All posts in WBS Summary

The Rookie Resource Mistake

My Least Favorite Activity Type