Yes, that is what I want, but I want the calculation to be independent of having to have all the dates in the table. I have a tab that provides the completions for the selected month. I want another tab that only shows the calculated difference over the previous month, quarter, or year.
There is a quick filter for date.
I only want a calculation that shows the filtered month-year/previous month-year (or month, quarter, etc). I do not want to show all the periods in the table, in order to use the Lookup() function. Is there anything to do with a 'previous period' calculation like the DAX query?
You can hide (different as exclude) previous year.
Another way is using a Month Parameter and creating a Calculated Field
Actual month: if month(DATE) = parameter then AMOUNT end
Last month : if month(DATE) = parameter -1 then AMOUNT end