I have a question from my Blog reader, and I’m going to explain the problem step by step. Of course I will use MS PROJECT 2016! My blog reader’s problem is written with Italic.
1. Let’s create a 5 days task with 2 resources. John is assigned at 100% and Mary at 50%.
I will now show Task Usage View with some additional fields:
- When the actual work is manually entered in Actual Work fields on either the table portion of the appropriate view or in the Timephased view, Project calculates Actual Duration and %Complete using straightforward approach with scheduling formula on the condition that the work that entered for each time period in the Timephased view is exactly equals to each resource assignment units.
So in the example below Project calculates Actual Duration = Actual Work / Total Units = 32hrs/150% * 8hrs/day = 2.67 days . From here all other values can be easily calculated.
Let me explain values from the picture above. when you enter Actual duration manually, day by day (or week by week…), formula Work = Duration * Units does not work anymore. Values are calculated like:
Actual Duration. For Monday and Tuesday –> Work = 12 hours (for John and Mary) per day and Actual work is 12 hours as well. So, Actual duration is two days because everything is done! At Wednesday, John and Mary were supposed to Work 12 hours, but Actual work was 8 hours, so Actual duration is 8/12 = 0,67. So Actual duration for whole Task is 2+0,67 0 2,67 days!
- But when the manually entered actual work does not correspond to resource assignment units in the Timephased view, the Actual Duration cannot be calculated using standard scheduling formula as in the example above. In this example the task’s Actual Work = 37 hrs, %Work Complete = Actual Work / Work = 62% and Duration = 5.63 days. This part is clear. But how does Project calculate Actual Duration = 3.67 days? If in this example Project calculates the task’s Actual Duration the same way it calculates the Duration of 5.63 days , the Actual Duration should be calculated as 4 days, not 3.67 days based on the actual duration of the driving resource John.
Let me explain values from the picture above. Since you know that formula Work = Duration * Units does not work anymore, Values are calculated like:
Actual Duration. For Monday, Tuesday and Wednesday are equal to Work, because when you enter Actual, Work field is automatically equal to Actual. So Monday, Tuesday and Wednesday are 3 days! At Thursday, John and Mary were supposed to Work 12 hours, but Actual work was 8 hours, so Actual duration is 8/12 = 0,67. So Actual duration for whole Task is 3+0,67 = 3,67 days!