how to show last quarter data in tableau

Question

I have a dashboard where I have data for each month for last 1 year.

Now I need to show data for last quarter (July-Sep)

Could anyone please help me what is the formula we need to write to get last quarter.

Answer 1

EDIT (based on question update):

sum(
    if (    QUARTER([Date]) = QUARTER(DATEADD('quarter',-1,TODAY()))
        and YEAR([Date]) = YEAR(DATEADD('quarter',-1,TODAY()))
       ) then [Value]
    end
)

If you're using Tableau version older than 2019.3, you have to replace QUARTER with:

datepart('Quarter', [Date])