Forcing Earned Values

[RobV]

I'm using MS Project to do research on Earned Value and need to have specific
EVs in specific time periods for each task in the test schedule. The
schedule needs to be dynamic, i.e., no constraints on tasks. I've been able
to get the Planned Values (BCWS) set up, but I'm having trouble getting MSP
to assign the required Earned Values (BCWP) within the target time period for
each task. I'd appreciate any ideas on how to make this work.

 

[Gérard Ducouret]

Hello Rob,

I don't really understand what you mean by "forcing" EV.
By default Project calculates the BCWS and BCWP while you or your resource
enter actual work (after you set the Baseline and the Status date)
You can display the BCWP in the Earned Value table, and also in the Task
Usage view (with a timescale)

Gérard Ducouret

 

[Andrew Lavinsky]

Just to add to Gerard's comments, is the issue the fact that the work in your
simulation is not being performed according to the schedule? Are you using %
Complete or Physical % Complete to calculate costs? If the first, I would
wonder if there's an issue with the update calculations and the Status Date
that is driving the issue.

Either switch to Physical % Complete or review the update options in Tools >
Options > Calculations (or is it Schedule - I don't have Project open in
front of me) and see if that perhaps is causing the work to be spread
inaccurately.

 

[RobV]

Thanks to both of you for the comments. Let me explain the challenge a bit
more. The test schedule needs to produce specific earned value by task in a
specific time period without introducing task constraints. I have included a
sample below. I have been able to manipulate (a better word than "force")
MSP so that it calculates the PV as required, but when it calculates the EV,
the costs in the target time periods are not exactly what they need to be.
What I'm trying to figure out is how to manipulate MSP so that it calculates
the EV in the pattern I require.

Here is a sample pattern of Planned Value, Earned Value, and Actual Cost.
By manipulating work and resource utilization %, I can get MSP to match the
PV. I can enter the AC manually. But, how do I get MSP to calculate the EV
in this pattern?
Jan Feb Mar Apr May
Task1 PV 5 5 5
EV 4 5 6
AC 5 5 7

 

[Andrew Lavinsky]

Let's say that you baselined with one resource having a standard rate of
$1/hr. For the task in question, you baselined at 15 hours over a duration
of 3 months.

Then, to get the numbers you seek, I would go to the Resource Usage view,
add the Actual Work row (right click on the chart), and zoom out so that
I see each cell representing a single month.

Then input your desired EV numbers in each of the cells. (i.e. 0, 4, 5, etc.).

Based on your AC, you run a cost variance of $2 at some point in the project.
To model this, you'll need to modify the overall Work for the task from
15 to 17.

That should get you close to what you need.


- Andrew Lavinsky
Blog: http://blogs.catapultsystems.com/epm

 

[Steve P]

Rob,

I believe I understand what you are looking to do. Let me restate: you want
to store the actual EV (BCWP) for every time period for each task.

EV is usually is calculated based on cumulative or ITD (inception to date).
data not period by period. Period by period data for Work Packages are
usually tracked in a separate cost tool the produces CPR reports. This is
usually not at the task level. The period by period EV is calculated from the
previous period cumulative value: Month 3 Cum - Month 2 Cum = Month 3 Period.

If you have MSP 2007, You might be able to use the Baseline1 thru 10 for
this purpose. You would need to save last period's cum EV value in a field
and subtract this period's cum EV valve and save it in this period's
Baseline1 field.

I don't have MS Project 2007 at home so I cannot verify. One of the MVPs
should be able to verify.

Steve P

 

[RobV]

Thanks, again, everyone. I appreciate the help. I have been using an
approach almost identical to the one suggested in Andrew's last post. The
only difference is that in manually entering the Actual Work I used the Task
Usage view, and I broke the view into days within weeks. I then entered the
actual values in the middle weeks of each month to ensure I did not overlap
with adjacent months. For some reason, when MSP calculates the EV for the
month, it does not come up with the expected EV. Rather than the expected
value of 4 for Feb in my example, it calculates $3.30. To do my experiments,
I need the exact earned value.

 

[Michael.Tarnowski]

Rob,

I believe I understand what you are looking to do. Let me restate: you want
to store the actual EV (BCWP) for every time period for each task.

EV is usually is calculated based on cumulative or ITD (inception to date).
data not period by period. Period by period data for Work Packages are
usually tracked in a separate cost tool the produces CPR reports. This is
usually not at the task level. The period by period EV is calculated fromthe
previous period cumulative value:  Month 3 Cum - Month 2 Cum = Month 3 Period.

If you have MSP 2007, You might be able to use the Baseline1 thru 10 for
this purpose. You would need to save last period's cum EV value in a field
and subtract this period's cum EV valve and save it in this period's
Baseline1 field.

I don't have MS Project 2007 at home so I cannot verify. One of the MVPs
should be able to verify.

Steve P

Steve,
what is a CPR report? Is this an acronym for cost performance?
Cheers Michael

 

[Andrew Lavinsky]

Not sure this is the case, but just so we can leave no stone unturned....in
your example, assuming you already calculated that the task would have an
overrun, then for Feb you should enter 4 X 1.13 (4.52). The way you're doing
EV, it's based on % Complete, which is Actual Duration/Duration. When Duration
has changed as it has in your example, you also need to change the numerator
to get the calculations you're looking for.


- Andrew Lavinsky
Blog: http://blogs.catapultsystems.com/epm

 

[Jim Aksel]

This is a good interchange! Let me throw a wrench in all of it for us.
There appears to be a bug in Project where BCWP (EV) is always spread to the
status date, not the task end date. I can illustrate in MSP that BCWP will
grow out to the status date, even if the task is completed on schedule and
precisely per the baseline. This is also true even if "spread costs to
status date" is UNchecked.

I have been in contact with Microsoft about this since March of 2009 through
March 2010. Their answer was this is legacy behavior (back to 2003). The EV
is accurate as of the status date, but does show variance to plan (baseline)
even if the task is worked per the baseline. So, your EV is good on the
status date; keep copies of the older files to retain proof.

Should you need more information, I have a PDF that explains it; contact me
at jeaksel at yahoo dot com.

---
If this post was helpful, please consider rating it.

Jim Aksel, MVP

Check out my blog for more information:
http://www.msprojectblog.com

 

[Marty]

Other comments have picked up the quirk in which MS project only
calculates EV up to Status date, eg you cant be ahead of schedule.
Its better to use a calculated field with a formula, basic one is Cost
1 renamed "Calc EV" and then use formula =[Baseline Cost]*[% Complete]/
100. For more sophisitcated calculations you could use Physical %
complete or other Earned Value Techniques. Remember the link between
% Complete and Actual/Remaining Duration.

In terms of History, short of using custom Baseline fields somehow the
simple solution is to store history outside the tool, eg Excel. Thats
why companion tools like Cobra and Winsight exist as EVcum is a point
in time calculation. A free download on our web site
(www.coreconsulting.com.au called "Simple Earned Value" might help.

Cheers

 

[Steve P]

Yes, CPR = Cost Performance Report.
It shows both Monthy and Cumulative BCWS, BCWP, ACWP, BAC, EAC, etc.

Steve P

 

[RobV]

Here’s my close to this thread. I’ve concluded that a dynamic (i.e.,
unconstrained) MS Project schedule cannot be manipulated to produce the
Earned Value by time period in the manner required for my research.

There were many excellent approaches suggested, but none of them worked.
Physical%Complete looked like a good bet, but a defect in the EV calculation
(see Jim Aksel’s white paper) erroneously spreads the EV across the duration
of a task, rendering it ineffective for my purpose. Andrew’s creative
suggestion to adjust duration in order to produce the target EV worked, but
only for a single period. By the time I got the tool to produce the correct
EV for the next period, it had automatically modified the EV for the previous
period. %WorkComplete looked like a good option, but the tool doesn’t
support generating EV based on it.

With no way to natively produce the desired EV by task by time period, I
believe the only approach is to develop a program that calculates the EV as
PV times (Actual Work / Work). The PV in Project is correct, and the Actual
Work and Work can be input in the desired pattern. It also appears that the
required values are timescaled. So, it should be possible to construct such
a calculation. Unfortunately, it will not match EV results produced directly
by the tool, making verification more difficult.

Comments I have gathered through the thread, emails, and conversations have
made me realize that there is widespread dissatisfaction with the way MSP
performs EV calculations. While this is an opportunity for third-party
developers, it’s disappointing that MS doesn’t respond to its core users and
fix the product.