tracking work and cost independently -- bug in MSP 2003?

[salilu]

I would like to track the work and cost associated with my MS Project task
independently using the external interface. Seems that I cannot do that in
MSP 2003.

Here is an example. I have a 5 day task with estimated work of 100 hrs. I am
not assigning any resources to this task but would like to track the work
done on it using the task level Work fields. Similarly for the same task I
would like to track the Cost INDEPENDENT of work using the task level Cost
fields. So I assign a Cost of $1000 to it using the task level Cost field.
Since I want to track the Cost and Work values independent of each other, I
turn OFF the option "Actual Costs are always computed by Microsoft Office
Project" in Tools - > Options -> Calculation window.

Now when the tasks starts I post 10 hrs Actual Work on it from a tool that
is externally interfaced. MS Project correctly sets the Actual Work to 10 hrs
and changes the Remaining Work to 90 hrs and keep the total work to 100 hrs.
So far so good. I haven't looked at the Cost fields yet since I am tracking
them indendent of Work and do not expect MS Project to make any changes to
them.

Now I post the Actual Cost of $ 200 on this task using the external
interface. I would now expect MSP to set the Remaining Cost to $800 and keep
the Cost to 1000. But Surprise Surprise --- my Cost is now $1100 and
Remaining Cost is $900.

On further analysis here is what I found--when I post the Actual Work of 10
hr, MS Project correctly calculates my Remainig work to be 90 hrs and then
changes my Remaining Cost to $900 ( in proportion Cost/Work). When I post
$200 of Actual Cost, MSP adds this $200 to the Remaining Cost of $900 and
changes the Cost to $1100. This is unexpected behavior and does not allow me
the track work and cost separately using the external interface. Is this how
the application is designed or is it a bug? How do I achieve what I want?

 

[Steve House [MVP]]

Not sure just what's going on here but there is a conceptual problem right
at the start that may partially explain things. You say you're tracking
work but not assigning resources. The unit of work is the "man-hour" and it
does not reflect the simple passage of time, that's duration. 10 hours of
work could be 1 man for 10 hours, 2 men for 5 hours, or 10 men for 1 hour.
Without resource assignments you are missing the "man" in the metric
"man-hour" and all references to work scheduled or performed are essentially
meaningless. Project ties all of its calculations together with the prime
directive W=D*E but without resource assignments E is indeterminate so the
results of its calculations are difficult to predict. For example, in
trying to duplicate your scenario I get different results depending on
whether I enter the Actual Cost and then the Actual Work in that order or
reverse the order of data entry and input first the Actual Work and then
Actual Cost.

 

[salilu]

teve,

I perfectly understand the concept of "man-hours" and duration. I case I
mentioned is a real life where I do not know who will be working on the tasks
but I roughly know that it takes about 100 hrs of work ( to be done by
multiple resources) over 5 days. When the tasks starts I report the actual
work and cost of all resources together at the task level.

Even if I assign a resource on the task and set up the project the way you
explained, the problem still pesists. Here is the case--

Task1 -- 25 days. Resource Bill@ $125/hr is assigned at 100% over the
entire period. So we have (in task Usage View)

Duration Work Act. Work Rem. Work Cost Act. Cost
Rem. Cost
Task1 25 d 200h 0 200h 25000 0
25000
Bill 200h 0 200h
25000 0 25000

Turn off the option "Actual Costs are always computed by Microsoft Project"
Note I assigned a rate to resource so that the Cost is compued based on work
and rate. MSP (I believe) does not allow me to enter Cost at the assignment
level. ( I do not know of any option for that)

Now post 20h of Actual Work for Bill. What you see now is:

Duration Work Act. Work Rem. Work Cost Act. Cost
Rem. Cost
Task1 25 d 200h 20h 180h 22500 0
22500
Bill 200h 20h 180h 22500
0 22500

MSP is not computing the Actual Cost here based on Actual Work but the
Remaining Cost ( and therefore the Cost) is computed based on the Rem. Work.
Now if I make the Task 100% Complete by entering the Actual Work of 200h,
the Remaining Work is set to 0 and Rem. Cost to 0. Since I have not yet
entered the Actual Cost., my Act. Cost, Rem. Cost and therefore the Cost all
are 0.

This behavior makes tracking of the work and cost independent of each other
impossible.

 

[Steve House [MVP]]

I see what you mean. But if you do set the task to 100%, the total cost
drops out the original cost of the resource work and reverts to just the
value you have manually entered into the actual cost. Using your figures
and setting work to 10 hours and entering $2000 as actual cost, your second
table there, it does in fact show remaining cost to be 22500 and total cost
to be 24500. But if you now set the task to 100% complete and enter $5000
in Actual Cost, remaining cost become zero, actual cost is your $5000
manually entered, and total cost is also $5000. While the total cost is
bogus while the task is in progress, once the task is complete it appears to
resolve itself and get back to reality.

As an aside, even if you don't know which resources will ultimately be
assigned, I'd suggest listing generic resources - senior engineer,
technician, etc - and doing the resource assignments anyway. The project is
a triangle of scope, duration, and resources and leaving off any side means
you only have part of the picture on hand to work with. You may not know
which engineers you'll have but if you know certain tasks need those skills
and you know how many you have to draw on, you can schedule your project
accordingly and avoid rude surprises later when you have more work scheduled
in a certain time period than you have resources available who have the
required skills. You can always come back later and fill in the names when
they're known.
--
Steve House [MVP]
MS Project Trainer & Consultant
Visit http://www.mvps.org/project/faqs.htm for the FAQs