You want to create a calculation like this:
IF [Date Type]="DÉPART TEMPORAIRE" OR [Data Type]="DEPARTURE" THEN "Group 1"
ELSEIF [Data Type]="HIRING" OR [Data Type]="RAPPEL" THEN "Group 2"
Now you have 2 new groups. Drop this new field out onto the view and then drop in your [Count]. I think this will return your desired results.
Not Exactly what i wanted, but gaves me an idea now on how to play with those fields
Oh right I guess you wanted something like this:
IF [Data Type]="DÉPART TEMPORAIRE" THEN SUM(Count) END
And so on for each Data Type field.
Right On - Yes more like that