UPDATING A TASK – Duration Calculations – Manual vs Timesheet Entry

BY:  Pete Evangelista

When a project schedule has both Local Resources and Enterprise Resources assigned to the same task there are some unique challenges that are presented to the Project Manager during the task update process.  The following example outlines how durations, work and other calculations are done by Project Professional 2010 and Project Server 2010 when the update process uses timesheets in Project Server.

We have been asked by Project Managers and Resource Managers as to why the duration of some of their tasks seem to increase into unexpected amounts.  In this case, they are used to manually updating the task in Project Professional directly.  But, now that they are using Project Server and getting updates from Project Server Team Members directly but when they go to manually update the Local Resource’s work they are seeing that the duration of the task is no longer what they originally set.

After some research, it was discovered that this happened whenever the Enterprise Resource updated their tasks but did not update it to 100% complete.  Here is an example and explanation of what is happening.

I have a task in my plan:  69- Review Sponsor’s Access to PMO site.  It’s a fixed worked task.  I set the work to 4 hrs and assigned myself (a resource in the pool who does timesheets) and Joe Sponsor (a local resource) each 100% to the task.  Project made a 2 hr task assignment for me and a 2 hr task assignment for Joe Sponsor on Wed 8/14/12.  Here is a snapshot of the Project Professional Gantt chart view:

Here is the TASK USAGE view from Project Professional (helpful for analyzing how resources are USED on TASKS):

Seeing that this is what I expect for myself and the local resource Joe Sponsor, I then save and publish the schedule.

Once on Project Server, I open my timesheet.  The task shows up as expected with 2 hours assigned to me.  For purposes of this example, I will update the task to indicate that I have spent 1.5 hours on it.  With no other time recorded on it and no other modifications or entries, I record 1.5 hours on 8/14 and I then save and submit that time:

After submitting the timesheet/task update and the Project Manager approving the task, this is what shows in Project Professional.  I went to the Task Usage view and insert the following columns for demonstration purposes:

Actual Work – 1.5 hours, just as I reported

Remaining Work – 2.5 hrs – .5hrs left for me, and 2 hrs left for Joe Sponsor.

% Work Complete – is a calculation based on Work.  I’ve done 1.5 of the 4 hours of work.  So, 1.5 divided by 4 is 37.5% (rounded to 38% by Professional)

Now, it gets a bit interesting in the Duration calculations..

Duration – .31 days (or 2.5 hrs) – This is because I marked 1.5 hrs done (75% done).  I still have .5 hours LEFT to go – in other words, .5 hrs / 8hr per day = .0625 days duration.  THE KEY ITEM is that because Project received the update from Timesheets, it assumes that NO MORE WORK will be done on that day.  It ADDS the remaining work to the currently scheduled duration.  In this case, add .0625 to the original .25 day duration to get .3125 days (rounded to .31).  So, the Fixed Work task remains at 4 hours BUT the duration has now been extended.

Note that the planned finish time is now 10:30 a.m., not 10:00 a.m.  We would expect that the new Finish Date wouldn’t be 10:30 on the same day but would rather put that 30 minutes on the next day since it is already assuming that the duration has to increase.  Maybe that is a bug?  Maybe that is an oddity of the way the calculation is done?  Either way, it does make logical sense that the duration has been extended based on our update.

% Complete –  is a calculation based on duration of the both resources over the total duration.  In this case, 1.5hrs / 4.5 hrs (total duration) = 34% (with some rounding).

Actual Duration – Is a calculation of Duration (now .31 days) *% Complete (.34) = .1054 or .11

Remaining Duration – Is Planned Duration of .3125 days minus the Actual Duration of .1054 (.11)  days to get .2071 days (.21 with rounding).

So, we understand why the Project Manager sees a Duration and Remaining Duration that don’t necessarily make sense at first glance.  However, the system is producing a logical result when broken down into its calculation method.

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