Compare with previous year

BassG , Try following measure

% Attend = DIVIDE(SUM(Data[Actual Attendance]), sum(Data[Possible Attendance]))
Last Year = CALCULATE([% Attend], OFFSET(-4, all(Data[Year], Data[Quarter],Data[Setting]), ORDERBY(Data[Year],asc, Data[Quarter],asc)))

file is attached

Hi BassG ,

Add a custom column with the Quarter end date then just use that column to make the calculations you need.

Code for the column is the following

Date.EndOfQuarter (#date([Year],Number.FromText (Text.End([Quarter],1)) - 1 * 3 + 3,1))

Hi BassG ,

You can add two tables to create slicers:

And there is no relationship between tables:

Use these DAXs to create measures:

Selected year attendance % = 
VAR Y = SELECTEDVALUE(Slicer[Year])
VAR Q = SELECTEDVALUE(Slicer2[Quarter])
VAR ACTUAL = SUMX(FILTER('Table', 'Table'[Year] = Y && 'Table'[Quarter] = Q), 'Table'[Actual Attendance])
VAR POSSIBLE = SUMX(FILTER('Table', 'Table'[Year] = Y && 'Table'[Quarter] = Q), 'Table'[Possible Attendance])
RETURN
DIVIDE(ACTUAL, POSSIBLE)

Previous Year's quarter attendance % = 
VAR Y = SELECTEDVALUE(Slicer[Year])
VAR Q = SELECTEDVALUE(Slicer2[Quarter])
VAR ACTUAL = SUMX(FILTER('Table', 'Table'[Year] = Y - 1 && 'Table'[Quarter] = Q), 'Table'[Actual Attendance])
VAR POSSIBLE = SUMX(FILTER('Table', 'Table'[Year] = Y - 1 && 'Table'[Quarter] = Q), 'Table'[Possible Attendance])
RETURN
DIVIDE(ACTUAL, POSSIBLE)

Difference % = [Selected year attendance %] - [Previous Year's quarter attendance %]

The final output is as below:

Best Regards,
Dino Tao
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