To be more clear, I would like to limit the number of day per week for my project manager (2 days per week).

It is exactly what will the affectation rate on the project : set to 40% will limit work at 2 days per week.

I tried to use the attribute "rate" but unfortunately nothing changed in my GANTT.

Once changes are done, you need to run planning calculation to take changes into account.

Thanks a lot for your reactivity.

I understand that "rate" is the attribute to split the workload.
Unfortunately, I don't understand the way of working.
Let me explain you (sorry if it is a basic question):

There are the attributes:
- assigned: It corresponds to the targeted number of days for an activity
- duration: It corresponds to the duration of task which can be different of the "assigned" attribute

Firstly the attribute rate is only dependant to the attribute "assigned", but it seems to be logic.
You can use Duration or Assigned independently but if you set both attributes, only assigned attribute will be taken into account in the GANTT

My problem is, if I set:
- Assigned: 1 day
- rate: 50 %
--> the GANTT is showing me 3 days of duration but normally it should be 2 days. (see the screenshot attached)

Is it a mistake from my side?

Thanks

Several possibilities to explain the behavior :
1) Capacity of resource if < 1. So full day for the ressource is < 1, 50% is < 0,5, extending duration...
2) maybe resource is busy on another task, on another project....
3) maybe resource uses a calendar with closed days during the period

Thanks a lot for your patience!
It was your first assumption :blush:

I will continue my tests!

See ya!