Need calculation for last 3 months average key-person distinct count including current month

Hi Team,

I am very new to tableau and Trying to get the last 3 months' average key-person distinct count including the current month. I have achieved that with the below calculation, but when I expand my report to week level it is automatically showing the average for week level. But I want to show month level average values in week level report.

Please help me with this requirement.

WINDOW_AVG(COUNTD([KeyPerson]),-2,0)

Requirement is like below

Message was edited by: DurgaMahesh Nalajala