Predecessor as percentage of duration of parent task

chris.mcintyre

Is there a way to have a predecessor as a percentage of the duration of a parent task? Example the parent task has a duration of X and we want to schedule a review to see where things are at 30% in from the start of the task. If the parent tasks duration was 30 days the review task would be on day 10.

Genevieve P.

Hi @chris.mcintyre

You can add Lag or Lead time to Predecessor relationships. Although this isn't a percentage, if you knew the number of days (so in your example 10 days), then you can subtract the remaining days from your Predecessor cell. E.g:

2FS -20d

Another option would be to change the relationship to be a start-to-start relationship and add Lag days:

2SS + 10d

See: Enable Dependencies and Use Predecessors

Cheers,

Genevieve

chris.mcintyre

Genevieve, That is not what we are trying to do and I am very familiar with the use of lag and lead times in predecessors. The duration in days between the parent and the sub task is a percentage of total duration of the parent task and the parent task duration changes frequently. In your example above the task 3 sub task predecessor for the parent task would be 2SS+30%. I am asking how do we set the predecessor as a percentage when the duration of Task 2 is unknown. Our projects normally have 12 plus subtasks per parent task that schedule like this and their parent task durations change frequently.

chris.mcintyre

@Genevieve P.

Without the percentage your answer does not address my question. Is there a way to have a predecessor as a PERCENTAGE of the duration of a parent task or a way to add a a formula in a predecessor?

Genevieve P.

Hi @chris.mcintyre

Thanks for the tag and the clarification!

There currently isn't a way to set the predecessor as a percentage in Smartsheet, and formulas cannot be used in Project Columns when dependencies are enabled.

You could set up formulas in columns either side as helper information, but it won't directly influence the date values.

When you have a moment, please submit your feature request to the Product team by creating an Idea Post in the Smartsheet Product Feedback and Ideas topic here in the Community. This will allow other users to vote on your enhancement request.

Cheers,

Genevieve

chris.mcintyre

@Genevieve P.

That does not help solve the issue. Are there no other options to work around this lack of ability with SmartSheet?

Genevieve P.

Hi @chris.mcintyre

Going back to your original post, what I would personally do in this instance is set up a new date column in my sheet for Parent Rows (instead of a task row).

Then I'd use a formula to output the "Review date" in this new date column for Parent rows. For example:

=IF(COUNT(CHILDREN([Task Name]@row)) > 0, Start@row + Duration@row * 0.3)

In my formula example I'm only looking at Parent rows, but since this Date column is not a part of the Project Settings, you could adjust this formula to automatically show a date for any of the rows in your sheet, with any percentage.

This date can then be used to trigger an alert, or conditional formatting, etc.

I hope that helps!

Genevieve

chris.mcintyre

How do we then set that as the start date for the review task?

Genevieve P.

Hi @chris.mcintyre

In my suggestion there isn't a review task. Instead, I'm using a review "column" that's associated with all the other tasks to automate alerts, reminders, etc. 🙂

You could add in a task row as an added row, but then you'll need to manually put lag/lead time as a number of days in the Predecessor field, as we discussed above.

Cheers,

Genevieve