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# Portfolios and Costs

13 replies [Last post]
Bogdan Leonte
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Joined: 18 Aug 2012
Posts: 284

Vladimir,

how does spider handle different costs of the same material/resource in portfolios. Let's take a concrete of class 8/10 (C8/10). If for one project the cost of pouring the concrete are 53.8 euro/m3 and for another the cost is 68.99 euro/m3, how does spider handle this when I create a portfolio using the 2 previous mentioned projects. To be more precise do I have to create 2 materials (with different codes)?

Best Regards,

Bogdan

## Replies

Bogdan Leonte
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Joined: 18 Aug 2012
Posts: 284

I took a closer look at the RoundTo() function in cost components formulas and it seems it works' a little different then when used in Formulas. In order to obtain the same result as the one using a User Field and Formula I have to consider an extra 2 decimals when entering the RoundTo(Field, no. of decimals).

For example:

RoundTo(Field, 5) [in cost components formula] = RoundTo(Field, 3) [when using User Field and Formula]

RoundTo(Field, 4) [in cost components formula] = RoundTo(Field, 2) [when using User Field and Formula]

RoundTo(Field, 2) [in cost components formula] = RoundTo(Field, 0) [when using User Field and Formula]

Also,

RoundTo(Field, 1) [in cost components formula] rounds the value before de decimal point.

RoundTo(Field, 0) [in cost components formula] yelds = 0 (more correctlly no value)

Regards,

Bogdan

Bogdan Leonte
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Joined: 18 Aug 2012
Posts: 284

The reason I am asking is because when I tried introducing the RoundTo function directly into the cost component formula I get a different result than the one using a User Field and a Formula and the result is not rounded to 2 decimals.

If it has any importance to the question I assigned the cost per unit of volume.

Vladimir Liberzon
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Joined: 5 Feb 2001
Posts: 2748

Bogdan,

Spider Project shows the number of digits that is defined for the project as default but permits to select another number of digits for each field. But it remembers the value and if you will change the number of digits for the field then the value will be rounded to new number of digits.

There is also formula like RoundTo(Field,2) if you want to round up to the second digit.

Bogdan Leonte
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Joined: 18 Aug 2012
Posts: 284

Vladimir,

is it possible to calculate cost component with a certain number of decimals using the RoundTo (formula, nr of decimals) or any other way?

Here are my result:

1-3.png

2-3.png

3-3.png

Bogdan Leonte
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Joined: 18 Aug 2012
Posts: 284

"We recommend to group portfolio activities in a separate dummy project to avoid entering actual data after the portfolio is consolidated."

I think this procedure will solve my problem. The basic ideea of my problem was that I didn't know how to update activities that belonged only to the portfolio, because syncronizing the 3 scenarios in the portolio doesn't work as in projects because of the different codes.

Example:

REMAT_TRGSV_A1-opt_RM_TRGSV - optimistic portolio scenario

REMAT_TRGSV_A1-cmp_RM_TRGSV - expected portfolio scenario

REMAT_TRGSV_A1-pes_RM_TRGSV - pessimistic portfolio scenario

If I try to syncronize optimistic portfolio it will not be possible because of the different codes, which makes sence. I was asking how to update activities that belong only to the portfolio. Your answer was very helpful

Best Regards,

Bogdan

Vladimir Liberzon
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Joined: 5 Feb 2001
Posts: 2748

Bogdan,

Some things in your post I did not understand.

Performance archive is the same for all project and portfolio versions. All uncertainties are in future.

We recommend to group portfolio activities in a separate dummy project to avoid entering actual data after the portfolio is consolidated.

I will try to follow your procedures to understand the problems that you met. The same performance archive does not prevent trend analysis.

Besides in consolidated portfolio you can select entering actual data and updating portfolio not by projects but by distributing and consolidating subprojects in responsibility structure (the same as in projects).

Regards,

Vladimir

Bogdan Leonte
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Joined: 18 Aug 2012
Posts: 284

Greetings Vladimir,

I have some questions regarding actual data input in portfolios, combined with 3 scenarios risk analysis. After entering the actual data input in each project, syncronizing and recalculating them I consolidate each scenario of the portfolio to a new version. My problem is that in the portfolio I have activities that do not belong to any of the projects in the portfolio, these activities need to be entered in the actual data input so I do it like in any project except I don't increase the portfolio version again.

Now for my question, at this stage do I syncronize the 3 versions of the portfolio? because if I do, after constrained scheduling in the pessimistic and expected scenarios I get the message that all the activities from my optimistic scenario have been added, event which also overwrites the performance archive of the expected and pessimistic scenarios, making it imposible to analyse any trend or perform risk simulation.

I suspect I'm doing somethig wrong, working whith portolios is pretty much the same as working with projects, yet a little different.

Thank you,

Best Regards,

Bogdan

Vladimir Liberzon
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Joined: 5 Feb 2001
Posts: 2748

Bogdan,

download new version. This problem was solved.

Regards,

Vladimir

Bogdan Leonte
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Joined: 18 Aug 2012
Posts: 284

I belive it works for any project, my problem is that I can't manage to see it, if you could follow my steps and tell me where I'm going wrong.

1. Create 3 scenarios for all my projects,

2. Create 3 scenarios for my portfolio each coresponding to the optimist, expected and pesimist projects scenarios,

3. Consolidate, schedule and cost calculate for each scenario,

4. In optimist scenario run risk anlysis (set each scenario, select the parametes, ex.: finsh, duration, excences cost center, etc., set optimistic/probable schedule, click apply to all versions, then hit ok)

5. After the risk analysis finishes, in the activity gantt, right click on any project wbs and select probability distributions->3 scenario method

P.S.: I managed to see the distributions for any phase/activity using the MC analysis. Surely I'm missing something.

Thank you,

Best Regards,

Bogdan

Vladimir Liberzon
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Joined: 5 Feb 2001
Posts: 2748

Bogdan,

updaing means looking for changes in the project files and implementing these changes into portfolio model.

You may notice that when the portfolio is created (just adding projects into portfolio) you can immediately get portfolio reports like portfolio budget, etc. without opening and calculating portfolio schedule and budget. These reports just summarize project data. Updating you renew these data can be achieved by updating.

Consolidating means opening portfolio model based on the latest versions of project portfolios. Projects in the portfolio are replaced by their new versions. This may cause priority changes if previous portfolio model was not distributed (new versions of project models sent from the portfolio model).

Three scenarios method shows probability distributions for any project and any phase of portfolio model. I checked it and in my portfolios it works as expected. But remember that for portfolios there are Project and Activity Gantt Charts. Risk analysis may be applied when you will open portfolio Activity Gantt Chart.

Bogdan Leonte
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Joined: 18 Aug 2012
Posts: 284

Greetings Vladimir,

again, thank you for clarifying the MC analysis for me, at leat I hope it's clear. I have some questions regarding portfolios:

1. What is the difference between updating the portfolio and consolidating the portfolio - I know that after inserting projects you have to consolidate them but I don't know when to use update vs consolidate,

2. When consolidating  I noticed that priorities are changed, this somewhat is related to the first question,

3. When performing a risk analysis (3 scenarios) I managed to see the probability distribution for the whole portfolio but not for any of it's projects, is there something I'm missing?

Thank you,

Best Regards,

Bogdan

Stephen Devaux
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Joined: 23 Mar 2005
Posts: 666

Hi, Bogdan.

This is not quite what your question -- but since you are asking about Spider Project and Cost Calculation, I'll point out that Spider is the only s/w package that, out-of-the-box, has the capability of computing the True Cost of Work (TCW).  That is because Spider is the only package that computes critical path drag (the Sumatra.com Project Optimizer add-on to MS Project is currently the only other product that does it) and, from what Vladimir tells me, can also compute drag cost.  Without that computation, the cost of doing any critical path activity can be hugely distorted.

Let us assume three tasks, X, Y and Z, on various parts of a time-sensitive project where the cost of every day of duration is estimated to be \$40,000.

X has a budget of \$100,000, a duration of 15D and total float of 12 days.

Y has a budget of \$80,000, a duration of 20D and drag of 2 days.

Z has a budget of \$30,000, a duration of 12D and drag of 10 days.

Measuring only the cost of resources leaves the impression that Z is by far the least expensive work. But:

• The TCW of X = \$100,000.
• The TCW of Y = \$80,000 + 2 * (\$40,000) = \$160,000.
• The TCW of Z = \$30,000 + 10 * (\$40,000) = \$430,000.

The implications of this are:

1. The impact of any increase in the cost of resources for X (more trucks, more labourers) will just be to increase its True Cost and the True Cost of the project.
2. The impact of an increase in the cost of resources for Y is in the balance -- a doubling of resources that reduces its duration by two or more days and thus removes its drag will result in exactly the same True Cost: 2 * \$80,000 + 0 = \$160,000.
3. The impact of an increase in the cost of resources for Z is probably to reduce its True Cost and the True Cost of the project: a quadrupling of its resources that reduces its duration to, say, four days (if it's not perfectly resource elastic) reduces its drag from 10D to 2D and the True Cost will be: (4 * \$30,000) + (2 * \$40,000) = \$200,000, or a saving of \$230,000.

The inability to compute drag and drag cost is a huge shortcoming in Primavera, Open Plan, Asta, and all other software that is not programmed for the calculation and therefore does not point the planner to where spending more money is hugely justified. No knowledgable planner would use a package that didn't compute total float, yet the inability to compute drag (which is always on the CP and therefore costing you time and lots of money!) is a much bigger drawback. So you are lucky you have Spider.

Fraternally in project management,

Steve the Bajan

Vladimir Liberzon
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Joined: 5 Feb 2001
Posts: 2748

Yes, create materials with different codes and Material Center "Concrete" where both materials will be included to get overall reports.

It is necessary not only when costs are different but also when you model material supply. If projects are performed at different areas materials are supplied separately and cannot be moved from one project to another.

Projects at different areas may use different reference-books that define different norms (crews, productivities, materials, costs, etc.). It is usual practice in large construction companies that have branches at different areas.

Best Regards,

Vladimir