How to calculate Average with Filters

Good morning,

I'm currently Power BI beginer and I try to learn how to use it in the good way.

I try to calculate average of error percentage with filters.

This is my data tables :

'Table test FX9600' :

'Table test LRU1002':

And my results table :

I want to calculate the average of error percentage (column:"Moyenne % erreur") with specific "Session" and "Type de lecteur".

The data is on my two other tables.

I try to solved this problem with the "SWITCH" command, but I think there is a better (faster) way to do this.

This is my command which works :

Moyenne % Erreur = SWITCH('Param Session'[Type de lecteur],
    "FX9600", SWITCH( [Session], 
                    "Session 0", CALCULATE(AVERAGE('Table test FX9600'[Erreur %]),'Table test FX9600'[Session]="Session 0"),
                    "Session 1", CALCULATE(AVERAGE('Table test FX9600'[Erreur %]),'Table test FX9600'[Session]="Session 1"), 
                    "Session 2",CALCULATE(AVERAGE('Table test FX9600'[Erreur %]),'Table test FX9600'[Session]="Session 2")
                ),
    "LRU1002",  SWITCH( [Session], 
                    "Session 0", CALCULATE(AVERAGE('Table test LRU1002'[Erreur %]),'Table test LRU1002'[Session]="Session 0"),
                    "Session 1", CALCULATE(AVERAGE('Table test LRU1002'[Erreur %]),'Table test LRU1002'[Session]="Session 1"), 
                    "Session 2",CALCULATE(AVERAGE('Table test LRU1002'[Erreur %]),'Table test LRU1002'[Session]="Session 2")
                ),
..........
)

Someone has any idea to simplify (and automate) this ?

Thanks in advance

Quentin