countrows based on slicer & related table

Hi,

I've got 2 tables

- one with my list of clients

- another with list of apointments related to clients with a date

I want to set a date slicer in excel to get the number of apointments per clients at a given date / date range

I have created a measure :

Date_selected:=max(tbmkg_apointment[Date_apointment])

and a calculated column in my client table but I either go the total number of apointment non related to distinct client with this formula

CALCULATE(
COUNTROWS(tbmkg_apointment);
FILTER (tbmkg_apointment;
tbmkg_apointment[Date_apointment]>= tbmkg_apointment[Date_selected] ) )

or a results taht take into account all apointments for one client even if only one of them is at the desired date:

CALCULATE(
COUNTROWS(RELATEDTABLE(tbmkg_apointment));
FILTER (RELATEDTABLE(tbmkg_apointment);
tbmkg_apointment[Date_apointment]>= tbmkg_apointment[Date_selected] ) )

Any insights?

Below is a data sample:

table client

table apointment

I want my calculate field in my client table in nb_apointment

Thanks!