Odd calculation behavior

[Pat Kelecy]

I have simple plan I've set up with six colums: baseline start, baseline
finish, baseline work, actual start, actual finish, actual work. I want to
compare planned with actual project data. I assume since units aren't
specificed (tasks have been set to "fixed work" types) that I can enter any
start, finish, and work values and it would use whatever units were
necessary to make it work. But when I enter actual start and finish dates,
MS Project automatically inserts an actual work value. I'm not sure what
it's using for units because the value is very large (81,966 hrs) even
though the start and finish dates differ by only two monthis. Also, if I
then enter a realistic actual work value, it changes the finish date to NA.
Does anyone know what's going? Is there a better way to do what I'm trying
to do?

Thanks for the help. -Pat

 

[Steve House]

What about just plain Start, Finish, and Duration? What are those values
showing?

Your assumption that units aren't specified is necessaarily valid. In fact,
"work" is a meaningless number until the number of resources who are
assigned to the task and the % of the working time is designated or
calculated. Until I know that I have "X" warm bodies who work Y hours per
day assigned on the task, there is no way for Project to relate work
performed to the length of time it will take to do it. There are three
elements to the work equation - Time, Rate, and Energy - in Project terms
Duration (time between start and finish), Effort (number of resources and
the rate at which they work), and Work (man-hours required). Project can
calculate 1 of those if the other two are known, but it cannot calculate 2.
We have to know how many resources are on the task and how much they're
avaialable to work. Once we know that Project can calculate the required
effort. To do so, Project must know both the duration and the total work
performed. I can specify the duration, mark the task fixed duration, and
supply the work (in that order) or I can set the total work for *each*
resource, mark the task fixed work, and then set the duration. In each case
Project will relate the constant value and the variable I supply and
calculate the effort. But I repeat, for that to happen properly it MUST
know how many resources are assigned and their working time calendar.

Another point - you are using baseline start, finish, and work but Project
does NOT use those values for the calculations you're looking for. It uses
the Scheduled values instead (hence my first question). The baseline is
simply a "snapshot" of what the schedule looked like at the instant the
baseline was saved. It exists purely for comparison purposes so you can see
the variance caused by any subsequent changes to the schedule, either
schedule revisions before posting actuals or posting actuals that differ
from planned. Schedule changes can cause a change to the baseline if you
wish to update it but entering values into a baseline DOES NOT drive a
change in the scheduled values. I can't state too strongly - the baseline
is NOT the schedule! It is a *picture* of what the actual schedule WAS at
some arbitrary time in the past, saved as a reference so you can see how the
schedule has evolved over time since then and/or compare performance against
plan.

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

 

[Pat Kelecy]

Thanks Steve for your detailed response.

As I'm sure you can tell, I'm pretty much novice when it comes MS Project
and am still sorting out what these different variables (i.e. baseline work,
work, actual work, etc.) really mean. Your suggestion of using just plain
Start, Finish, and Duration resolved the problem. I now realize (and the
point of my confusion) that "Acutal" values really only have meaning once
"scheduled" values are defined. The reason I'm using baseline values is
that I've been asked to show the current progress (task hours and dates) on
a project compared to what was originally proposed for it (hence the
baseline). So for each high level task I would like to show two Gantt bars:
one showing the original projected (baseline) start, end, hours (per the
original proposal for this project) and the other showing the actual
figures. If you have any suggestions for how to best do this, please let me
know.

As far as Time, Rate, Energy (or Work) goes, really all I wanted to do was
show the start and finish dates (Time) and number of hours spent (Work) for
each task, and not worry about who did the work or how many hours per day
they spent on it. This is all for a presentation to my sponsor and not for
project management use where such resource details would be needed.

If you have any other suggestions please let me know, and thanks again for
your help.

Pat

 

[Jan De Messemaeker]

Hi Pat,

Just rapidly this.

Quote:
So for each high level task I would like to show two Gantt bars:
one showing the original projected (baseline) start, end, hours (per the
original proposal for this project) and the other showing the actual
figures. If you have any suggestions for how to best do this, please let me
know.

That is exactly what the tracking Gantt view does!

HTH

--
Jan De Messemaeker
Microsoft Project Most Valuable Professional
Project Management Consultancy
Prom+ade BVBA
32-495-300 620

 

[Steve House]

Thanks Steve for your detailed response.

As I'm sure you can tell, I'm pretty much novice when it comes MS Project
and am still sorting out what these different variables (i.e. baseline work,
work, actual work, etc.) really mean. Your suggestion of using just plain
Start, Finish, and Duration resolved the problem. I now realize (and the
point of my confusion) that "Acutal" values really only have meaning once
"scheduled" values are defined. The reason I'm using baseline values is
that I've been asked to show the current progress (task hours and dates) on
a project compared to what was originally proposed for it (hence the
baseline). So for each high level task I would like to show two Gantt bars:
one showing the original projected (baseline) start, end, hours (per the
original proposal for this project) and the other showing the actual
figures. If you have any suggestions for how to best do this, please let me
know.

As far as Time, Rate, Energy (or Work) goes, really all I wanted to do was
show the start and finish dates (Time) and number of hours spent (Work) for
each task, and not worry about who did the work or how many hours per day
they spent on it. This is all for a presentation to my sponsor and not for
project management use where such resource details would be needed.

If you have any other suggestions please let me know, and thanks again for
your help.

Pat


if

 

[Steve House]

Ooops - hit the wrong button

An easy way to see both the baseline and the schedule is to right click on
the Gantt Chart, chose the "Gantt chart wizard" to reformat the chart, and
select the "baseline Gantt". You'll see blue bars for the current schedule
and grey bars for the saved baseline.

The reason resources are important is due to the difference between work and
duration. Duration is the length of time the task takes to complete
disregarding non-working hours - if we work a default schedukle and it
starts Mon at 8am and finishes Fri at 5pm its duration is 40 hours (5 days).
But the *work* is the amoiunt of energy it takes to do the task and that
could be anything. If I have one guy working full time he does 40 man-hours
of work during the 40 hour duration. BUT, if he works at 10%, about an hour
a day, he does 5 man-hours of work during the 40 hour duration. OTOH, if I
have 10 guys all working full time on it, they do 400 man-hours of work
during the same 40 hour duration.

If 400 man hours is required, I can have 10 people do it in one week, or 5
people do it in 2 weeks, or 1 guy do it in 10 weeks or 1 guy doing 2 hours a
day and it will take 20 weeks.

 

[Pat Kelecy]

Thanks for the suggestion and further explanation. I saw the Gantt wizard
and already did what you suggested. So I think this is starting to come
together. -Pat