Microsoft Project cost calculation issue (error?)

Question

Hi All,

I am relatively new to Microsoft Project. I use Project for software implementation projects, from small to medium size.

I understand the mechanics of input, and for the most part things have gone fairly well.

One issue I am having is in costing for tasks when there are more the 1 resource for a task.

I've noticed the costs not agreeing with what seems to be the same calculation in Excel.

My concern is I may be missing something simple due to my inexperience in using Project for the budgeting of my projects.

I am using Microsoft Project 2016. I've also installed the trial version of the Project Professional installed today 2/8/2020.

I've created a simple project for test purposes, and have also created an Excel worksheet to check my calculations.

I have a task for 1 resource named P-1, with a resource cost of $146.00 USD. The task has 480 hours of work.

Project calculates the total cost as $70,080.00 which is correct.

I have a task for 1 resource named G-1, with a resource cost of $20.00 USD. The task has 480 hours of work.

Project calculates the total cost as $9,60.00 which is correct.

My third task is where the calculation is incorrect as explained below.

My task 3, with 2 resources, P-1 used for 60% and G-1 used for 40% displays a cost of $39,840.00 which is incorrect. The real cost should be $45,888.00.

Resource sheet is below. Yes they are over-allocated.

 

Task entries showing costs below

Task information showing the units below

My concern is I am overlooking something obvious to more experienced people here in this community.

Any help, coaching, etc will be much appreciated.

Answer 1

You haven't assigned the resources at 60% and 40%. You have assigned them both at 100%. Each has 240 hours of work at their respective rates.

I checked it with a pencil and paper. It's all correct.

How did you assign the resources to the task? Did you use resource, assign resources?

Answer 2

Hi Trevor,

I just did a test by creating a new project.

Opened the Resource Sheet and entered the resource name and standard rates.

Opened the Gantt view and created a task with 480 hours.

Went to the Resource> Assign Resources and chose the 2 resources and applied the 40% and 60% units.

You already know the outcome. :-)

A CORRECT calculation!

Thank you for leading me to the solution.

I do have a workflow question as a result of this learning.  Should I never do the assignments and units splitting directly in the Gantt Resource Names column? I realize the Assign Resources will derive the correct calculation, but I can't see a reason why the direct entry method is any different.  The final inputs in the Resource Names column look identical, but there must be some jiggery-pokery going on behind the scenes.

Answer 3

Hi Trevor,

The resources are now assigned at 60% and 40%.

Still incorrect amounts.

I assigned the resources while in the Entry view of the Gantt/Tasks view.

Is the way I did it incorrect?

Answer 4

Hi Eric,

I followed your steps and verified. The issue still persists.

I will try the suggestions in the other reply prior to sending a screenshot.

Thank you for the reply.

Answer 5

Hi threeforks,

I'm willing to help you.

Please try following basic troubleshooting steps to narrow down the issue.

• Check that all resources are assigned to tasks. Note that costs are calculated only after resources are assigned to tasks.
• Check the cost rate table that you have applied to the task. A cost rate table that does not contain rates may have been applied. You can change the cost rate table for the resource assignment.

1. Choose ViewTask Usage.

In the Task Usage view, resources are grouped by the tasks they are assigned to. 2. Double-click the resource who is assigned to the task for which you want to verify its associated cost rate table. 3. In the Assignment Information dialog box, in the Cost rate table list, verify that the cost rate table is the correct one for the task.

If the issue still persists, please capture a screenshot of your File > Account page. (Please mask personal information on the screenshot to protect your privacy).

Regards,

Eric