TotalFloat inconsistency between parent and child tasks

Paul M Kahl

I am looking to utilize TotalFloat in a project plan and am finding inconsistent results with parent and children tasks.

The sheet is set to Mon-Fri working days with no holidays set.

The formula in use is =TOTALFLOAT([Task Name]@row) + " days"

From what I am seeing:

-The manually calculated delta between Line 14 and Line 15 is 23 days, which is correctly reported by the Float formula on line 11 which is the parent task of line 14

-However, the manually calculated delta between Line 14 and Line 23 (the last date in the plan) is 43 days, which is reported by the formula on lines 12-14

So unless I am missing a setting or am not leveraging predecessors to the best degree, parent tasks seem to work fine with my formula but child tasks calculate to the final date on the plan. Looking for any advise or insight on this.

Julio S.

Hi @Paul M Kahl

In doing some testing and replicating your sheet configuration I have found some discrepancies at first in my calculations when predecessors were used. Since the TOTALFLOAT function is fairly new, I am unable to determine whether this behavior when using predecessors is or not expected at this point. If you haven't done already, I would recommend opening a ticket with Support via this form if you'd like this to be further investigated.

Cheers!

Julio

Paul M Kahl

Hello @Julio S.

Thank you for testing and for the feedback. I did contact Support and they provided the following feedback. Seems careful attention needs to be paid to predecessors and best practice established for constructing a timeline...

"TotalFloat() function calculates the number of days that a task can be delayed without impacting the Project Finish Date. Since the child case has no other rows linked to the tasks, therefore the total float function will calculate the number of days the task can be offset based on the end date of the project. 

"If you want it to be calculated based on the previous parent case, I highly advise adding a predecessor on the row. Doing this will limit the number of days to be evaluated."