Summary task and EVM values

[Tom]

Is there any documentation available describing if the EVM values are
calculated or roll-up from detail? Also, has anyone validated Project's
calculations of the EVM fields?

 

[Jim Aksel]

Sooner or later the values are calculated. I actually don't have access to
the code but the values for BCWS, BCWP, and ACWP must be summed up. Values
for the other EVM parameters such as SV, CV, SPI, CPI can be calculated from
the summed values on the summary lines. You don't sum up an SPI...

I have done some extensive checking on the EV and and have concluded when
you input a proper status date, the EV as of the status date calculates as
expected. The Help explains how the values are calculated and I have never
found something there that I disagree with. Some things on the Task/Resource
usage views require some investigation on my part to fully understand what is
going on. I need to look into that.

If you have a specific concern, or an anomoly you'd like to discuss you can
post it here or donate the file to jeaksel at yahoo dot com and I will see if
I can look at it tomorrow.

Perhaps if you can tell us what you want to do with this information we can
be more helpful. Keep in mind, no one here works for Microsoft, we are just
folks with our own opinions.
--
If this post was helpful, please consider rating it.

Jim Aksel, MVP

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

 

[Tom]

Thank you for the feedback. I will forward you a file to look. In this
example, EV is higher than what I calculated in Number1. I referenced the
'help' for the formulas and have been working through each EVM calc. Since
EV is a major input for all other EVM values, it is skewing my results, to
the point that I have only slight faith in all my EVM values calculated by MS
Project 2007.

Note: In this example, the actual work was started weeks ahead of the
baseline. I'm not seeing these same calculation errors when the actual work
matches the plan.

 

[Jim Aksel]

Tom, I took a look at your plan. Here is what I can offer.
When a task is first created, the BCWP is 0.00. As soon as a baseline is
saved and progress is reported for the task (by actual work, actual duration,
or percentage of work complete), timephased BCWP is calcualted for the task.

The percent complete = (Actual Duration)/(Duration) is compared with the
task's baseline duration. Project then calculates the cumulative baseline
cost to that point of the baseline duration and provides the value of what
the task's actual costs should be, given the task's percentage of completion.

The behavior seen on a task given an early start is consistent with this
information. The early start increases the task [duration] but not the
[baseline duration]. The actual duration is being calculated as the number
of days for which you have entered a value in [Actual Work]. In your case
the %Complete is 21%, duration is 24 days, [Actual Duration] is 5 days and
[Baseline Duration] is 10 days.

Project is calculating 21% x 10 days or 2.10 days of duration. It then goes
into your baseline and determines the baseline value of the first 2.10 days
of your task whish is the $166.67 value being shown.

So, the program is calculating as designed.

Personally, I would use Physical%Complete. I have a white paper on the
topic posted to my blog is that is of interest.

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

Jim Aksel, MVP

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

 

[Tom]

Jim,

Thank you for your assistance. You're correct! But now I'm reviewing how
the BaseLine Cost was calculated. It should be $800, but it is showing $600.
The first place I'm looking is resource overallocation! I'll let you know
if I see what's wrong.

Tom

Tom, I took a look at your plan. Here is what I can offer.
When a task is first created, the BCWP is 0.00. As soon as a baseline is
saved and progress is reported for the task (by actual work, actual duration,
or percentage of work complete), timephased BCWP is calcualted for the task.

The percent complete = (Actual Duration)/(Duration) is compared with the
task's baseline duration. Project then calculates the cumulative baseline
cost to that point of the baseline duration and provides the value of what
the task's actual costs should be, given the task's percentage of completion.

The behavior seen on a task given an early start is consistent with this
information. The early start increases the task [duration] but not the
[baseline duration]. The actual duration is being calculated as the number
of days for which you have entered a value in [Actual Work]. In your case
the %Complete is 21%, duration is 24 days, [Actual Duration] is 5 days and
[Baseline Duration] is 10 days.

Project is calculating 21% x 10 days or 2.10 days of duration. It then goes
into your baseline and determines the baseline value of the first 2.10 days
of your task whish is the $166.67 value being shown.

So, the program is calculating as designed.

Personally, I would use Physical%Complete. I have a white paper on the
topic posted to my blog is that is of interest.

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

Jim Aksel, MVP

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

Thank you for the feedback. I will forward you a file to look. In this
example, EV is higher than what I calculated in Number1. I referenced the
'help' for the formulas and have been working through each EVM calc. Since
EV is a major input for all other EVM values, it is skewing my results, to
the point that I have only slight faith in all my EVM values calculated by MS
Project 2007.

Note: In this example, the actual work was started weeks ahead of the
baseline. I'm not seeing these same calculation errors when the actual work
matches the plan.