Task Control - Actual Start and Actual Finish Wrong data

Copper Contributor

Hello team.

My restlessness is quite old, but I'm still looking for answers. The idea and never give up as long as there are great people like you to help me. I'll make available a download link of the file(!Agg30WAoUvdLgQYFgEIcz4yt_Hop?e=va0rii ), where you find a sketch so that you can see what I say and draw your conclusions. Ready let's get down to business. My question is: how does the worksheet use the task, when and updated the actual effort of the resource with imputation units to tasks other than 100%? The task type is fixed duration. It turns out that whenever I intend to update the actual effort (actual work field – Worksheet task usage) of a resource being that it has the unit less than 50%. The Actual Start and End real fields give me unusual data.

See the following example in the image.

  • Update the effort of a resource imputed with 100% the task: Resource 1 is scheduled to fulfill 60 min. work, but your actual work will be 30 min.

Picture 1.png

  • I get as a result in the fields Home and End Real (24/01/22 08:00 - 24/01/22 08:30), which we can agree is definitely right.

Now let's see when we work with resources that have units of less than 50%. 

Note: You can see the percentage of the feature in the image in the first line in Detail View


See the following example in the image.

Updating a resource that is allocated with 10% of the task. Feature 2 is scheduled to serve 6 minutes. work, but your actual work will be 3 min.


Picture 2.png


  • I get as a result in the fields Home and End Real (24/01/22 08:00 - 24/01/22 08:30), which we can agree not to agree with this result is definitely wrong. The error remains case third Resource with 5% completes its work of only 3 min.

Picture 3.png


  • The image shows that Feature 3 in the Start and End Real fields had one hour of work.

Ready these are my little doubts that make me lose sleep. I've done enough research but no answer. I need you to make me understand. Thank you, team.

4 Replies
best response confirmed by Dale Howard (MVP)

My, my aren't we having fun! The scenario you present is interesting and in fact, was a challenging one for me to figure out. I couldn't do it with Project 2019 running on Windows 10 with my Parallels virtual machine, I had to revert back to Project 2010 running on Windows 7 ( a much faster and more responsive configuration).

Okay, I've got your answer, you may or may not like it. To understand what is happening, I had to set the timescale to hours (middle tier) and minutes (bottom tier). Even then Project would not reliably display Work in the timescaled data but it did display Cumulative work in the timescaled data and that allowed me to figure it out. (It helps to look at the face of an analog clock to visualize the information below.)

The task is 60 minutes duration. The first resource is assigned at 100% so those hours are spread linearly over the full 60 minute task duration, one minute of work for every minute of duration. The second resource is assigned at 10% with 6 minutes of work and those 6 minutes are assigned linearly over the full task duration which translates to 1 minute of work for every 10 minutes of duration. Thus, when that resource shows an actual work content of 3 minutes with zero remaining work (i.e. 100% complete), those 3 minutes span 30 minutes of duration so that resource's finish time is 8:30, not 8:06 as you might assume.

A similar thing applies to the third resource with an assignment level of 5%. Those 3 minutes of work are spread linearly over the full 60 minute task duration (i.e. 1 minute of work every 20 minutes of duration).

That is how Project schedules the task. If you want a different spread of resource hours, (e.g. resource 2 works for 6 minutes all at the very beginning of the hour), you will need to change the task type to Fixed Work and manually adjust the work time directly in the Finish field for the resource's assignment row (i.e. enter 1/24/22 8:06 AM).

Whether I've made you understand, I do not know. But I do know, you probably owe me a beer, a Mercedes Benz and 10,000 in bitcoin for digging this one out for you. :)


Ha, ha, ha
Thank you John.
When I find my lamp genius I will fulfill your wishes... Hugs
But given the confusing situation because of the task type being Fixed Duration. Is it a program error or is it its natural way of calculating working time
You're welcome and thanks for the feedback.

No, it's not a program error, regardless of task type, Project will always linearly spread resource assignments across the full task duration, assuming the user did not change the assignment Work Contour which is "flat" (linear) by default. But, manually editing those assignments to a non-linear spread is dependent on the task type. It all depends on which of the three variables in Project's work equation is fixed.
Duration = Work / Units