Concept: Early investments in time, money, and political influence make it difficult to call out the need for project recovery. And, it’s even more difficult to take action. That’s one reason failures happen so often: the time to act has long-since passed.
When hesitation results from uncertainty, facts matter. Quantitative measurements combat the uncertainty. In such situations, Earned Schedule can help.
Practice: ES recovery metrics offer multiple perspectives on project recovery. Thresholds mark the boundaries for recovery. Once a threshold is breached, the project can be considered unrecoverable. Before that, trends help you assess the need for recovery.
In posts over the past few months, Pros and Cons were cited for each of the recovery metrics. Here is a summary of the Pros and Cons. It is followed by the example that was used throughout the posts. Links to details on each metric are highlighted.
Overall Pro:
- Quantitative metrics resist cognitive bias (unconscious mistakes). They can also combat strategic misrepresentation (deliberate lies), but sometimes, facts matter little in the face of deceit.
- TSPI is the foundation for all the metrics, and it is supported theoretically and empirically.
Overall Con:
- Complexity of the underlying math and some of the calculations challenge adoption. (Note: it’s not necessary to understand details of the math in order to use the metrics successfully. And, tools are available for all of the calculations. But, the initial perceptions intimidate users.)
Individual Pro and Con:
TSPI gives the level of performance required to recover the target date. Once the threshold of 1.1 is breached, the project can be considered unrecoverable. Trends toward the 1.1 threshold trigger recovery.
Window of Opportunity tells what room (percentage) is left to recover the project. Once there’s no room left (percentage = 0), the project can be considered unrecoverable. Trends toward the 0 threshold trigger recovery.
Improvement Profile shows what level of performance is required in each of the recovery periods. Comparison to the maximum SPIt achieved previously guides recovery. If the performance level required is within the maximum, proceed with recovery. If the performance level required exceeds the maximum achieved, the project can be considered unrecoverable.
Probability of Recovery gives the likelihood that the project will recover. Once the threshold of 50% is breached, recovery is still possible, but action must be taken quickly. Trends toward the threshold can signal the need for recovery before a breach actually occurs. Calculation of the probability is complex, but automation helps.
Example
Say that at month 6 in a 10 month project, the To Complete Schedule Performance Index looks like this.
The late start and nil SPIt throw off the first measurement. The other measurements seem to be hovering below the 1.10 threshold. There’s no clear signal to start recovery.
So, what do you do?
Don’t ignore the situation and hope for the best. Don’t flip a coin. Get more information.
Another measurement from Earned Schedule helps: the Window of Opportunity.
Based on current performance, the Window of Opportunity for recovery is .132.
To put that into perspective, if all the remaining time were available, the Window would be 1.000. If no remaining time were available, it would be 0.000. So, it’s possible, but the Window looks small.
You might think, “Wait, the project is only 60% complete. Surely, recovery is possible with a full four months to go!”
Dream on.
Walt Lipke’s research has shown that once the TSPI hits 1.10, recovery is very unlikely. The math behind the Window of Opportunity is tied directly to that break point. The Window measures the time available before the threshold is breached.
So, it’s not four months of runway. It’s less than 15% of the remaining timeline, or about 16 days. Not four months; instead, about one month. At the current level of performance, the project will be unrecoverable in a month.
The percentage is informative, but a picture is better.
The graph highlights the difference between the time left in the Planned Duration and the time left before 1.1 is breached. After period 3 (March), the proportion gets smaller and smaller. It’s no surprise that the clock will run out by the next month.
With just a month to recover, it would be prudent to take action now. But, it’s possible that you might still hold off the decision. Recovery is a dramatic step, and a Window remains open.
Fortunately, there’s other information that helps us decide: the Improvement Profile, for one. (See below: the dotted line and four rightmost columns in the table). The Profile identifies the efficiencies required in each period of the Window.
Look at the required efficiencies and see if the project achieved similar efficiencies in the past. Also, you can check whether or not the required rate of change is similar to the rate achieved earlier in the project.
The answers tell you whether recovery is realistic for your project. If so, there is good reason to start down the road to recovery.
In the graph and the table, the previous efficiencies are followed by the recovery efficiencies.
The recovery efficiencies are striking. Almost all of them exceed the maximum efficiency attained thus far.
Furthermore, after a sharp initial increase, previous efficiency leveled off--well below the needed level.
That’s more reason to start recovery.
And, yet, it might be argued that the desired recovery rate appears to be lower than the rate achieved through the first three periods--the slope of the first increase appears to be sharper that of the second.
It might be that the project is capable of attaining a rate as high as the one required.
That’s a thin thread, but it’s a reason to hold the decision in abeyance.
The final recovery metric, Probability of Recovery, decides the case.
Suppose that, in the example, another month has elapsed, and it’s now the end of July. Efficiency remains essentially unchanged at .958. Consequently, the SPIt and EACt remain much the same (and are not shown).
With the shortening of available schedule, however, the TSPI and Window of Opportunity are significantly altered. TSPI rises to 1.097, slightly below the threshold. The Window of Opportunity shrinks to .006, slightly open.
Strictly speaking, neither measurement breaks a threshold value, and so, neither is shown. Recovery is still possible, although intuitively it seems unlikely.
The final recovery metric decides the issue.
The probability of successful recovery peaks in April. [1] Then, from April through June, its decline is unremittent. That’s bad enough, but in July it gets worse.
The decline not only continues; it reaches 50.82. And, that’s a threshold.
At 50%, successful recovery becomes a matter of chance. Recovery should depend on more than a roll of the dice. It demands action, and so, delay is no longer an option. It’s time to recover the project. [2]
[1] Although there is Planned Value for January and February, there is no Earned Value for January. To calculate probability, you need at least a couple of periods of EV. So, probability can’t be calculated until March.
[2] Starting recovery a month earlier would have been appropriate. At that point, there were already three periods in which the window of opportunity narrowed, requisite efficiencies climbed, and probability of success dropped. The trends make it reasonable to take action without waiting to hit the threshold. |
