What will happen depends on the adjustment you make. For instance,
Joe and Bill are both working on a 5 day task 100%, 40 hours each (to
make the numbers easier). Now if you change Joe so he does 60 hours,
leaving Bill at 40, the duration will increase. But OTOH, if your
edit instead had been to *reduce* Joe, changing him from 40 down to
20 hours but still leaving Bill at 40, the duration would NOT change
because Bill's 40 governs the whole duration since it's the longest.
Without exception, the duration is from when the first bit of work is
done (no matter who does it) until the last bit is done (again,
without regard to who does it).
Be careful mixing up allocation with the percentage of a resource's
time spent - it only works out like that due to averages. Strictly
speaking, the allocation is the efficiency with which the resource
converts time to work. 50% Allocation means that out of every hour he
puts in, he only gets 1/2 hour of full-time equivalent work output. A 1
day task at 50% does not last 4 hours. It lasts *8* hours but
only gets accomplished what the resource would have been able to do
in 4 if he didn't have other things on his plate to distract him.
Here's some examples of some of the possibilities.
5 day (40 hour) duration task - Joe at 25% means he does 10 man-hours
of work over the course of 40 hours of working time, Bill at 50%
means he does 20 man-hours of work over the course of 40 hours of
working time. Fixed Work task type, both resources start together.
Case 1: Increase Bill to 75%. Joe still does 10 hours of work, still
taking 40 hours at 25%. Bill still does 20 man-hours but @ 75% it
only takes him 26+ hours to do it - the increase from 50% to 75%
means he's working faster. But Joe's duration at 40 hours is the
longest, hence the overall task duration per se remains at 40 hours.
Case 2: Decrease Bill to 25%. Joe still does 10 hours of work at
25% for a duration for him of 40 hours. Bill still does 20 man-hours
of work but now at 25% it will take him 80 hours of duration. Bill
being the longest governs and task duration increases to 80 hours, 10
days.
Case 3: Increase Joe to 50%. Joes work at 10 man-hours now only
takes 20 hours of duration to do because he's working faster. But
Bill (20 hours work, 50%) is still at 40 hours duration. Bill's time
governs and task duration doesn't change.
Case 4: Decrease Joe to 10%. Joe's work at 10 man-hours now takes
100 hours of duration to do. His is now the longest so the task
duration becomes 100 hours, 2.5 weeks
Hope this helps
uo said:
Thanks but what I want is one resource to put in say 25% of their
time throughout the duration and the other resource 50%, again
throughout the duration. Work should be fixed and I expect when I
adjust the allocations the
duration to change (BTW, it happens sometimes and sometimes not).
Steve House said:
Remember that duration is the time between when work begins and
when it ends. If you have two resources, the duration is from when
the first one starts until when the last one leaves. So lets say
Bill works 40 hours and
Joe works 20, both starting at the same time, if you add a little
or take away a little from Joe it won't change the duration of the
task as a whole
since it's Bill's 40 hours that are initially in control.
--
Steve House [Project MVP]
MS Project Trainer & Consultant
Visit
http://www.mvps.org/project/faqs.htm for the FAQs
I have a task with multiple resources with various percentage
allocation.
Sometimes I change the allocation of one resource and neither work
nor duration changes. I've tried fixed units, fixed resources and
fixed duration.
The result is the same, i.e. nothing changes. If I delete the
resource and
add it again with a different percentage allocation then it works.
Why can't
I go to any task and change resource allocation at any time and
see the new
duration? Sounds pretty basic to me but I guess I am doing
something wrong.
Help! Thanks in advance!.
