Sorry, I misunderstood what you were looking at when I sent my previous
post. There are two different "allocations" - the allocation percentage on
individual task assignments allocation percentage and the total usage
allocation during a given time period.
An assignment allocation of 100% means that he is devoting his full,
undivided attention to the job at hand. I'm painting a room. Working at a
normal pace I can apply 10 square feet per hour. The walls total 400 square
feet, thus it requires 40 man-hours of labour. If I start Monday and have
no distractions, I'll finish the room Friday afternoon, 40 working time
hours later. But if I'm shooting the breeze with a buddy at the same time,
I'll work slower. If I talk 50% of the time and paint 50% of the time, it
will take me 2 weeks to do that same 400 square-foot room. The total work
is still 40 man-hours but the time to do it will expand to 80 working time
hours. I'm allocated 50% to the painting task. Remove the buddy from the
picture and add another painter to work alongside me. We still must do 400
square feet and 1 hour of 1 painter's time still accomplishes 10 square
feet. There's still 40 man-hours of work to be done. But now we have two
painters, each working 100%, so we get 2 man-hours of work done for every
clock hour that passes. The total resource allocation is 200% and we get
the job done in a total of 20 hours.
The resource allocation numbers you see in the resource usage view are
interpreted slightly differently. Instead of dealing with the ASSIGNMENT
percentages, they do deal with the total man-hours the resource is committed
to compared to the total man-hours he's available during the time period
specified by the smallest division of the timescale.
Create a project, set its start date to May 3 and put a single 5-day task in
it. Create resource Joe and assign him to the task at 100%. Go to the
resource usage view and add the "% Allocation" line. With the default
settings you should see Weeks and Days as the tiers in the timescale. You
should see Joe scheduled to work 8 hours per day for one week and his
allocation percentage day-by-day should be 100% each day. Switch to the
Gantt chart and display the assign resource dialog. Edit his assignment
percentage to 50%. The duration will change from 5 days to 10 days. Return
to the Usage view. Now you'll see 4 hours per day listed, the duration will
be 2 weeks, and his allocation will be 50% each day. Note thatat 50% he's
still working the entire day but he's only getting 4 hours of FTW work
accomplished each day. Right click on the timescale, choose "timescale".
Set the middle tier to quarters and the lower tier to months. In the month
of May he will be working 40 hours and his allocation will now read 24%,
because he's working a total of 24% of the total hours he's available during
the month of May. Add another 5-day task, link it FS from the first one,
and assign Joe to it at 100%. Back in the usage view you'll see he's
40hours/24% on the first task, 40hours/24% on the second task, and
48hours/48% in total. Go to the Project menu, Project Information dialog
and change the Project Start date to April 27th. This pulls both tasks back
a week. The usage view now shows 16 hours/9% done in April on the first
task, none on the second with a total for the month of 16h, 9% of April's
total possible hours. May shows 24h, 14% of the available total on the
first task, 40 h, 24% of the total hours for the second task, and a total
for both of 64h, 38% of the available work hours in the month. Now go back
to the default timescale settings with a middle tier of weeks and a lower
tier of days. You'll see the percentages change to reflect the number of
man-hours per day he's actually getting done compared to the number of
man-hours he could achieve each day.
Hope this helps
