Milestone task child in a % complete parent roll up

I have a number of milestones (0 duration lines) in my projects. These represent decisions, meetings, inspections and deliveries. I also use % complete to communicate with our finance department, customers and project team members. These factors don't seem to play well with each other in the schedules I have set up so far.

My project schedule sheets function as Gantt + dependencies. When I have a child line with a 0 duration in with several other children with a >0 duration, the % complete roll up on the parent line is blank even if all the children report a % complete. In addition, if that parent has a grandparent line, that % complete roll up treats the blank parent as if it was 0%.

Showing accurate percent complete and using milestones is very important to my stakeholders.

Any thoughts?

I would love suggestions. I am likely missing something.

Thanks Community!!

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Comments

Travis

Hi Justin! Good question - the parent rows roll up the child row percent complete by taking a weighted average based on percent complete and duration. Because milestones have a duration of 0, they are not counted in the rollup. If you want to include these items in your parent row percent complete rollup, you would need to change the duration to 1. This would change the diamond icon to a square but you could format this to be black to make it stand out as a milestone.

Justin Philips

Travis,

Thanks for your response. I have been doing what you suggested and it will work for my projects. Percent complete is more important to me than the milestone concept, so that is what I am focusing on.

I understand the math behind having a % of a duration 0 item and why the calculation won't work. Right now milestones are a penalty to the calculation. It seems like a simple solution is to have the % complete roll up exclude milestones in the weighted average. There could even be functionality that will "grey" out the cell for % complete if you change a task to 0 duration. That would satisfy the math purists out there who cannot accept a % of nothing

Thanks again Travis!

Travis

Justin - milestones should be omitted from the rollup calculation completely. Here’s an example:

Are you finding they are counting against the parent percent complete?

Screen Shot 2015-04-29 at 10.58.18 AM.png

Justin Philips

Here is what I am running into.

Justin Philips

I am discovering the root cause as I go here and I can see what you pointed out to be true. The % complete for any milestone doesn't affect the roll up result (as it shouldn't) and when it is mixed in with other lines that have a duration value, there is no issue.

The problem shows up when I have a single child that is a milestone, the parent is affected. The error might be in the fact that the parent shows a duration of 1 when the milestone child has a duration of 0.

Travis

Thanks for the screenshot - it helps! You are correct, it this stems from the parent row showing a 1 day duration (parent rows cannot be “milestones” with a 0 day duration). In your example, the grandparent is calculating percent complete based of its two children (Parent 1 and 2). Milestones are not included in parent rollup percent complete, so Parent 2 is 0% complete. The grandparent is taking the weighted average form Parent 1’s 3 day 100% complete tasks and Parent 2’s 1 day 0% complete tasks. You will run into this if you only have milestone child rows.

Stephanie Clark

I am wondering what I'm missing here? Why would the parent reflect 63% when all children tasks reflect 100%. Thanks!

capture image 3.png

Greg Hawk

Stephanie - Row 221 is pulling the average from its children, including row 228, which is blank. Because this is blank, is messing up the rollup. Try changing the duration in rows 229-231 from “5 days” to “5”.

Stephanie Clark

Well of course, thanks!

John Meunier

I am no longer using the milestone feature as the overall % complete feature is more valuable. The nested milestone should be calculated as a 1day and the 0 ignored. This would solve the problem and milestones would should up correctly in the % complete column.