Usually we assign resources to a project as a percentage of time by day/week/month for the duration of the project.
e.g. Here you can see I'm assigned to Example Project at 100% from April to July:

If I'm only needed for 75% of May, I can switch to Flexible mode and change the entry for May - however this displays the effort by hours, not by percentage. I am forced to manually calculate what 75% of 176h is and enter that number.

How can I enter 75% for May instead of being forced to enter the correct number of hours?