Project Summary calculation

[Chilvers]

I have a 57 day project and I marked the first task 100% complete. It is a
2-day task completed on 2 days. On the Tracking Table, why does my Project
Summary show Actual Duration 2.07 and Duration Remaining 54.93 rather than
Actual Duration 2 and Duration Remaining 55

 

[Gérard Ducouret]

Chilvers,

The sum of elementary tasks is meaningless when several tasks are running in
parallel. So the % Complete which is a % in duration. If you assigned
resources on tasks, use the Actual Work, Remaining Work, and/or % Work
Complete....

Gérard Ducouret

 

[JulieS]

Hello Chilvers,

The .07 variance you are seeing is most likely a 1/2 hour difference
between the setting on you calendar and the definition of a "day"
duration set in the Calendar options. Check FAQ #5 at:
http://project.mvps.org/faqs.htm

and confirm that your settings are correct.

I hope this helps. Let us know how you get along.

Julie
Project MVP

Visit http://project.mvps.org/ for the FAQs and additional information
about Microsoft Project

 

[Chilvers]

Hi Julie
My calendar options show 8 hours, 8:00-5:00 as does my calendar, so I don't
see any problem there... any other suggestions?
Chilvers

 

[Chilvers]

Hi Gerard
I don't have any other tasks running in parallel. I just want the Project
Summary Task to show the correct status (2 days instead of 2.07 days)
Chilvers

 

[JulieS]

Hi Chilvers,

Try showing time as well as date. Is there a half your difference
somewhere on the completed task as compared to the Project Summary task?

I hope this helps. Let us know how you get along.

Julie
Project MVP

Visit http://project.mvps.org/ for the FAQs and additional information
about Microsoft Project

 

[JulieS]

Sorry, fingers not fully talking to brain. The message should have
said:
"Is there a half hour difference...."

Julie
Project MVP

Visit http://project.mvps.org/ for the FAQs and additional information
about Microsoft Project

 

[Chilvers]

nope... my task is 16 hours and it was completed in 16 hours (two days at 8
hours a day)

I have seen this happen on other projects as well... I have another project
that I marked 3 tasks totallying 4 days complete and the project summary
shows 3.78 days instead of 4...

Training Manual Mon 10/1/07 NA 7% 3.78 days
Research Phase Mon 10/1/07 Thu 10/4/07 100% 4 days
Interview Subject Matter Expert Mon 10/1/07 Mon 10/1/07 100% 1 day
Investigate the software Tue 10/2/07 Wed 10/3/07 100% 2 days
Search the Web Thu 10/4/07 Thu 10/4/07 100% 1 day

Chilvers

 

[JulieS]

Hello Chilvers,

Instead of guessing and if the project file does not contain highly
confidential information, if you'd care to zip the file and send it by
email, I'll take a look and see if I can see anything unusual.

My email address is:
pass port 6847 AT maine.rr.com

Remove spaces and change the AT to an @

I hope this helps. Let us know how you get along.

Julie
Project MVP

Visit http://project.mvps.org/ for the FAQs and additional information
about Microsoft Project

 

[Steve House]

It's very likely it IS showing you the correct status (can't tell for sure
without seeing the details of the entire plan). % Completions on summary
tasks, including the Project Summary Task, are weighted averages based on
the progress of their 'children.' So what you're seeing is a computed
'effective' duration based on the sum of the actual durations that have been
worked on all the performance tasks divided by the sum of their total
durations and then multiplied by the duration of the Project Summary Task.
There is no reason at all to expect this effective actual project duration
to be the arithmetic sum of the actual durations of the performance tasks.

 

[Chilvers]

Thanks Steve
I guess I was expecting to see a logical total rather than a weighted average!
Chilvers

It's very likely it IS showing you the correct status (can't tell for sure
without seeing the details of the entire plan). % Completions on summary
tasks, including the Project Summary Task, are weighted averages based on
the progress of their 'children.' So what you're seeing is a computed
'effective' duration based on the sum of the actual durations that have been
worked on all the performance tasks divided by the sum of their total
durations and then multiplied by the duration of the Project Summary Task.
There is no reason at all to expect this effective actual project duration
to be the arithmetic sum of the actual durations of the performance tasks.
--
Steve House [Project MVP]
MS Project Trainer & Consultant
Visit http://www.mvps.org/project/faqs.htm for the FAQs

Hi Gerard
I don't have any other tasks running in parallel. I just want the Project
Summary Task to show the correct status (2 days instead of 2.07 days)
Chilvers

 

[Steve House]

While work is an additive measure, duration is not. Consider an extreme
case - I have a project with two tasks, each of 2 days duration. Task 1
starts 26 Nov 8 am, finishes 27 Nov 5pm. Task 2 requires parts that are on
backorder and won't be available until 03 Dec so the task can't start until
then, task 2 starts 03 Dec 8am, finishes 04 Dec 5pm. Proect total duration
is thus 26 Nov 8am to 04 Dec 5pm, or 7 days. It is Friday, 30 Nov and we
are updating progress. Our resource tells us he worked on Task 1 last
Monday but then got called away for the rest of the week so only one of the
two scheduled days was worked. Total required duration of all tasks = 4
days. Total duration actually worked = 1 day. 25% of the project's
required duration has been worked. Project's effective completion expressed
as duration = 25% * 7 days = 1.75 days.


--
Steve House [Project MVP]
MS Project Trainer & Consultant
Visit http://www.mvps.org/project/faqs.htm for the FAQs

Thanks Steve
I guess I was expecting to see a logical total rather than a weighted
average!
Chilvers

It's very likely it IS showing you the correct status (can't tell for
sure
without seeing the details of the entire plan). % Completions on summary
tasks, including the Project Summary Task, are weighted averages based on
the progress of their 'children.' So what you're seeing is a computed
'effective' duration based on the sum of the actual durations that have
been
worked on all the performance tasks divided by the sum of their total
durations and then multiplied by the duration of the Project Summary
Task.
There is no reason at all to expect this effective actual project
duration
to be the arithmetic sum of the actual durations of the performance
tasks.
--
Steve House [Project MVP]
MS Project Trainer & Consultant
Visit http://www.mvps.org/project/faqs.htm for the FAQs

Hi Gerard
I don't have any other tasks running in parallel. I just want the
Project
Summary Task to show the correct status (2 days instead of 2.07 days)
Chilvers

:

Chilvers,

The sum of elementary tasks is meaningless when several tasks are
running
in
parallel. So the % Complete which is a % in duration. If you assigned
resources on tasks, use the Actual Work, Remaining Work, and/or % Work
Complete....

GÃf©rard Ducouret

"Chilvers" <[email protected]> a Ãf©crit dans le
message
de
news: (e-mail address removed)...
I have a 57 day project and I marked the first task 100% complete.
It
is a
2-day task completed on 2 days. On the Tracking Table, why does my
Project
Summary show Actual Duration 2.07 and Duration Remaining 54.93
rather
than
Actual Duration 2 and Duration Remaining 55

 

[billm]

Hello Chilvers,

Instead of guessing and if the project file does not contain highly
confidential information, if you'd care to zip the file and send it by
email, I'll take a look and see if I can see anything unusual.

My email address is:
pass port 6847 AT maine.rr.com

Remove spaces and change the AT to an @

I hope this helps. Let us know how you get along.

Julie
Project MVP

Visit http://project.mvps.org/ for the FAQs and additional information
about Microsoft Project

 

[billm]

Hi, I was following your work I am having similar problems
I am doing simple scheduling using elapsed time edays, eweeks and emons - as
they are contract dates/times. I used scheduled F/S and a "None "calendar
settings for all the tasks.
I found the summary duration comes out incorrectly.
By further testing simple 2 sub-tasks at 30edays each , the summary = 2.05
months, by messing around with the subtask durations I found that there is a
default setting of 28 days/month for the "None" calendar setting.
Any ideas how to achieve real Julian calendar months/weeks?in the summary
task duration - these are contract times so rather important.

 

[John]

Hi, I was following your work I am having similar problems
I am doing simple scheduling using elapsed time edays, eweeks and emons - as
they are contract dates/times. I used scheduled F/S and a "None "calendar
settings for all the tasks.
I found the summary duration comes out incorrectly.
By further testing simple 2 sub-tasks at 30edays each , the summary = 2.05
months, by messing around with the subtask durations I found that there is a
default setting of 28 days/month for the "None" calendar setting.
Any ideas how to achieve real Julian calendar months/weeks?in the summary
task duration - these are contract times so rather important.

billm,
The only way to achieve real calendar durations for months is to set up
a spare text field and then use an algorithm in a VBA macro to calculate
the actual elapsed calendar month time.

Probably not the answer you wanted, but Project just does not have
custom monthly calendarization capability when it comes to calculating
durations.

John
Project MVP